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Aphototaker
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Posted on Thursday, February 25, 2010 - 09:22 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I am not very familiar with flashes. I have a Canon 380 EX that I have used with an Elan 50e and with a G5, but only in E-TTL mode. I used an old flash with a Canon FT QL camera several years ago but I don't remember the specifics, besides I was kid and hardly payed attention to such technicalities.

Now, I have a Canon FTb and an AE-1 Program. I understand both have an X-sync speed of 1/60 sec max.

I have measured their shutter speeds and both are have an error of around +2% at 1/60 sec, i.e. they are both slower by that margin. So we can assume they are both accurate within specs.

I have also confirmed that there is no shutter capping and no shutter bounce at this speed.

What is left to do is to verify the x-sync synchronization (is that what it is called?) at 1/60 sec. How do I do that without having a manual flash handy?

I am able to detect a peak of voltage using my audio card. I have a DMM at hand and various electrical components, but no oscilloscope.


Finally, I would appreciate if somebody can explain how does a X-sync contact actually work in these kind of old cameras such that it triggers the flash.

Thanks.
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David_nebenzahl
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Posted on Thursday, February 25, 2010 - 09:38 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Why are you bothering with this stuff? Why not just put a damn flash on the camera, take some pictures with it and confirm that it works? (The ground everywhere should be thick with cheap flash units.) If it doesn't, then you can worry about flash synchronization and start fooling around with audio cards and such.
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Rick_oleson
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Posted on Thursday, February 25, 2010 - 09:51 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

An X-sync contact is not a very complicated device: it consists of 2 pieces of metal that touch each other while the shutter is open. One of these pieces is wired to the rail of the flash shoe, and the other is wired to the center contact. That's all there is to it.

All that matters is that the shutter be fully open at the moment when the 2 pieces of metal touch. It couldn't care less how close to the specified speed the shutter is. The obvious way to check synchronization is to attach a flash unit, remove the lens, open the back door and look through the shutter as you fire it off. You should see the whole rectangle of the film opening brightly lit. If the flash fires but the film opening looks dark, then the synch is off (in practice, this means that the camera has fired on bulb synch rather than X synch); if you see only part of the film opening lit, you have selected too fast of a speed. If the flash doesn't fire at all, you probably have a wire off.

I don't know of a reliable way to check flash synch without a flash.
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Aphototaker
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Posted on Thursday, February 25, 2010 - 10:07 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Okay. I was hoping to be able to verify this without a flash; I don't have one yet.

Though I am looking for a flash, I haven't yet made up my mind which one to get which would be most versatile (recall that I am not very familiar with these, still reading up on the technical stuff). Perhaps a one that works with FTb as well as with T90 and can tilt and swing.

Since I now know that the x-sync is just a shorted circuit when the first curtain opens, it sould be fairy easy to verify this quantitatively. Consider the following method.

1.Detect that short circuit at x-sync. Fairly easy to detect using a voltage drop across a resistor.
2. Detect the opening of the first curtain. Easy to detect using a photo diode.
3. No shutter capping/bounce occurring.
4. Shutter open interval is accurate.

If (1) occurs within 1/60 sec. of (2) (can be measured by detecting both using a stereo cable and an audio card), and if (3) and (4) are satisfied, then it has been shown that the x-sync is working is properly. Makes sense?

Rick, I have read something called the x-sync voltage in various flash units. Is this the voltage across the two contacts of the flash unit that touch the hot shoe or PC terminals which get shorted as the shutter is released and fire the flash?


Thanks.
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Rick_oleson
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Posted on Friday, February 26, 2010 - 04:41 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

This sounds like driving east and going 24,000 miles to get to the town 5 miles to your west. It may work but I can't think of a more difficult way to accomplish a simpler task. Any flash with a hot shoe foot and a PC cable will work on virtually every mechanical camera made after about 1955, you can probably get one for $5. If your goal is actually to find a new way to play with a sound card, then go for it.

As for your specific questions: what matters is that the shutter is open when the flash fires. So (2) must happen first, then (1). The other thing that you have to detect is the beginning of movement of the closing curtain... this must not happen until after (1) has occurred ((3) and (4) are irrelevant to flash synch). You would need a second photodiode to detect this, so that the first one can verify that the opening curtain is fully open (placed at the left side of the frame) and the second one (at the extreme right side) can verify that the closing curtain has not yet begun to move. With enough apparatus and instrumentation, you can make this work. But pushing a button with your eyes open is much faster and gives you more and better information.

The x-sync voltage is the voltage in the flash that passes through the sync terminals when the connection is made. This doesn't matter in mechanical cameras where the terminals are a metal switch, and in older flashes it can be very high - one of my flashes measures 70V across its terminals, I'm sure some went much higher than that. New cameras that use semiconductors instead of mechanical switches are voltage sensitive, so you don't want to pop one of these old flashes onto your DSLR withoug checking it out first. You can read the voltage across the terminals on the flash when it's charged and waiting to fire.
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Aphototaker
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Posted on Friday, February 26, 2010 - 06:51 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

ha ha ... I understand your car analogy. But I don't have a car yet, so driving the short distance is out of the question :-)

$5, eh? Well, if you say so. But background reading of all that stuff about x-sync voltage has made me over-cautious, I suppose. Would this voltage matter in an Canon AE-1 Program and in A-1 cameras? I know that AE-1P has a flex circuit in side. How can I tell from the specifications of a camera that the x-sync is just a mechanical switch and not an electronic one?


Your interpretation of (3) and (4) is interesting. I was thinking along the lines that if these points are satisfied, then a second diode is not necessary (it will only show these two points, but at once). But, yes, the second diode will simplify this whole detector thing a bit, though a bit of trick is needed to read three signals on an audio sound card with 2-channel input :-). Anyhow, since you guys both suggest that using a flash and naked eye can give the same information with no hassle, I will abandon this instrumentation hack method.


Regarding that x-sync voltage, you write:
"The x-sync voltage is the voltage in the flash that passes through the sync terminals when the connection is made."

I am assuming you are stating that the voltage that builds up across the flash's terminals is the x-sync voltage. And that these two terminals are shorted when the connection is made.

It is just that the phrase you used, "the voltage in the flash that passes through the sync terminals," I have never come across this in electrical engineering. Current passes, voltage builds up. Sorry for the nitpick, but this a very strange way to put it, at least to me, hence the clarification.

Coming to flashes and their costs, I have narrowed down my choices to the following (none of which are available for $5, I am afraid):
Canon 199A
canon 299T
Vivitar 283 or 285 HV
Sunpak 383

Any comments regarding these choices?

Thanks.
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Mndean
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Posted on Friday, February 26, 2010 - 10:09 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

The Vivitar 283 is one that can be problematic depending on its age. The older ones can put out a high voltage, which can be deadly to DSLRs and other cameras with sensitive circuits. Later 283s don't put out high voltage. Problem is, there are precious few ways to tell them apart without testing. I'm not really sure about the 285, and I think the Sunpak is okay. Easiest (not cheapest) thing is to buy a Canon flash intended for your camera. Best choice is one for your T90, since most flashes are backwards compatible. I have a 360px designed for my Minolta X-700, still works with my SRT cameras, and I get the advantages of TTL flash with my X-700.
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Tom_cheshire
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Posted on Friday, February 26, 2010 - 12:02 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

This reminds me of the guy on usenet a few years ago who was asking where to find the battery compartment in an SLR that didn't use a battery. When told it didn't need a battery to operate his response was "That's impossible. How does it work then?" :-) Man, do I ever love those newbies.

Think of it this way: get two wires connected to a light bulb and a battery. Hold one wire on one end of the battery and touch the other wire to the other end of the battery. Touch, it is on. No touch, it is off. Simple. That is X flash contact inside a camera. Two pieces of metal passing in the night releasing all that pent up energy in the capacitor. The energy goes through and "excites" the xenon gas in the flash tube, a quick flash and it is over. The only problem some synchronizers develop is, ahem, "premature" firing. :-)

To be safe, if the camera is digital, buy a new flash for it. If it uses film, don't worry.

T designated flashes are designed for T series Canons.

What you really want is a good D series Sunpak flash (266D, 344D, 422D, 433D).
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Aphototaker
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Posted on Friday, February 26, 2010 - 12:56 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Yes, I am a complete newbie as far as the inner working of flashes and their protocols with cameras are concerned (isn't PC still an undefined or un-disclosed 'standard'?).

Tom, I have had a question a few number of times that goes like this "Nice camera! Does it take color photos?". :-)

Yes, I got it that flash x-contact is just a metal switch in old film cameras and a semi-conductor switch in modern digital cameras.

Now I may be using wrong terminology here so just to confirm: in film cameras the x-sync switch gets closed at all speeds, but only at 1/60 (usually) or slower is the proper exposure expected? At the same time the PC connections also get shorted?

Also, is the nature of the x-sync and PC the same in modern film cameras (Canon EOS 5e, EOS 1N and EOS 50e) or can they also have semiconductor switches?

I notice that most of the flashes have some contacts at the bottom. Let us assume it is working in AE-1. How would it work on a Canon FT QL which does not have any contacts at its base ... mounting that flash on FT's shoe would just short all the flash's contacts!

Meanwhile, off to the eval-bay to look for those D flashes.


Sorry for all the basic questions, but trust me, once I am through with the background reading, I will know all the basics about this topic :-)
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Agno3
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Posted on Friday, February 26, 2010 - 03:13 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

You can also build/buy a small device that will lower the voltage the camera receives through the contacts. Wein makes one; it fits in the hot shoe and has a pc socket on the back too, to it can work via hot shoe or pc cord.

It contains a small transformer that isolates one circuit from the other but fires the flash via the voltage induced in the winding not connected directly to the flash.
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Rick_oleson
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Posted on Friday, February 26, 2010 - 05:20 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

"It is just that the phrase you used, "the voltage in the flash that passes through the sync terminals," I have never come across this in electrical engineering. Current passes, voltage builds up. Sorry for the nitpick, but this a very strange way to put it, at least to me, hence the clarification."

You're right, current flows, voltage is the potential that causes it to flow. And you're also right, that's a nitpick.


http://cgi.ebay.com/Universal-Flash-for-SLR-35mm-camera-from-Pentax-camera_W0QQi temZ260558462415QQcmdZViewItemQQptZDigital_Camera_Flashes?hash=item3caa7e9dcf

http://cgi.ebay.com/CANON-AB-46-flash-w-4-AA-bats-no-cord_W0QQitemZ140384936890Q QcmdZViewItemQQptZDigital_Camera_Flashes?hash=item20af9823ba

http://cgi.ebay.com/SUNPACK-Softlite-1600A-Electronic-Flash_W0QQitemZ38020849942 3QQcmdZViewItemQQptZDigital_Camera_Flashes?hash=item5886314adf
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M_currie
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Posted on Friday, February 26, 2010 - 05:36 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

For a hot shoe flash in a cold shoe, you can just put a little piece of tape or plastic between the center pin and the shoe.

You can easily check that your sync is synced by firing the flash with back open and no lens on. Hold it a little away from you and look through the open back. Set it to a speed you know is above the sync speed if there's any doubt about what you're looking for.

Some older cameras will have a second PC connection for bulb flash, but the X terminal should short out at the very same time as the hot shoe does, and operation will be the same with hot shoe or PC cable connector. An exception here is the old Nikon F, which has a single connector, and a switch for various sync settings, all of which are duplicated at both PC and shoe connections.

The flash-end connectors for PC cords are not standardized, so if you're looking to shoot one with the cold shoe, make sure your flash comes with the right cord. Some that look similar are not as similar as they look.

Remember that these days if you're in the US, you can usually find a quite serviceable digital multimeter for as little as ten dollars, and a really nice and versatile one for 20-odd. There's almost no excuse these days not to have one, and with such a tool, you can test your flash terminals, and when you find a good looking flash, you can test it for trigger voltage too.

Electrical engineering aside, what you must be concerned with when using old flashes with newer camras is the trigger voltage - the potential, if you must, that is switched by the sync switch. There's little current involved here at any voltage, but many older flashes use high voltages that will fry electronics.

If you're shopping for flashes, bookmark this page:

http://www.botzilla.com/photo/strobeVolts.html
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Tom_cheshire
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Posted on Friday, February 26, 2010 - 06:08 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Ok, PC is short for Prontor-Compur (the two dominant shutter companies during the 1950s) when the PC flash contact was adopted as the standard "nipple" (as I call it) to which you connect any flash (electronic or flash bulb) by using a wire from the flash to the PC.

Other flash contact types of that bygone era were the ASA (ASA=American Standard Assoc.), which was a push on and twist bayonet type seen mostly on American and early Japan cameras, and pin plugs/jacks that were two separate plugs, one for ground and one for positive, which were mainly seen on cameras like the early Pracktica and Exakta.

Ok, now, the Canon FT has a regular accessory shoe on top known as a "cold" shoe since no wires go to it. The means of connecting a flash is via the PC connection thingy on the front (below the mirror lock up switch). On this camera you will need to use a wired flash. Nearly any good flash will work with it so long as it has a wire connector.

An accessory shoe having a flash contact is known as a hotshoe. When the hotshoe has a few extra tiny metal contact points then it is a dedicated hotshoe. Dedicated hotshoes can have as few as one extra contact point or up to five. I believe the Canon AE-1 Program has two such extra points in its hotshoe. The reason a dedicated flash is called dedicated is because it can only be used with whatever camera brand it was built for. However it can be used on a standard hotshoe usually, of course, without the automation. The automation you get with a dedicated flash can be as simple as a flash ready light in the viewfinder all the way up to fancy 2nd curtain sync. What features the AE-1P or A1 has is best learned from the user manual. Many after-market flashes are dedicated and available in many brand names. The Sunpak D series flashes have pop off interchangeable modules which allow you to use their flashes with whatever camera system you have or change to by simply changing the "foot".

Ok, now X sync. simply means the flash waits for the shutter to be completely open before it goes off. X sync. can happen at whatever speed the camera maker has made it to be. 1/60th is usually the X sync. speed for horizontally running cloth focal plane shutters (like the AE-1P). Cameras using a Copal Square metal focal plane shutter, which moves vertically, usually have X sync. at 1/125th. Later improvements in shutters increased the X sync. speed to 1/250th as seen in the Nikon FE2 and FM2n. X sync. simply means the shutter is wide open when the flash goes off. It is not any specific speed.

Now, to further confuse you, there are also such things as M sync. and FP sync. M sync. is for flash bulbs and sets off the bulb slightly before the shutter has opened completely so that the bulb will reach full brightness when the shutter reaches the point of being totally open. FP sync. is the same thing but for focal plane (FP) shutters. M sync. is mainly used is non-SLR cameras. And, lastly, cameras using inter-lens or bladed shutters (the shutter is built in with the lens), like the Hasselblad or Rolleiflex, can sync. at any speed.

As for using a hotshoed flash on your FT, well, when you plug the connector cord into the flash it overrides that contact point so it shouldn't short out (since you asked).
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Mndean
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Posted on Friday, February 26, 2010 - 06:20 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

For a cold shoe (one that has no sync contacts), just get an aftermarket hotshoe that slides into the cold shoe and hook the integral wire to the X-sync socket (some flashes like the Vivitar 283 have a hard-to-find X-sync connector, so it's easier this way). I have one I use for all my older cameras, it's simple and effective.
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Aphototaker
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Posted on Friday, February 26, 2010 - 07:43 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Tom, you didn't confuse me. I spent some time today reading some literature on flash photography and technology and you have summarized the relevant parts to this discussion very well. Your post actually made the perspective much clearer. Thanks.

Mndean, I was also coming around to the same idea of getting hot shoe add on.

That stobevolts website is already bookmarked. I have been reading portions of it here and there.

Rick, thanks for the links, all of which I missed because I have been searching the Canadian ebay (.ca domain). Based on your links, I am going to search on their .com domain now.

Thanks, folks. I appreciate all these useful comments.
Regards.
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M_currie
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Posted on Saturday, February 27, 2010 - 04:17 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

By the way, when I was warning about non-standard PC cords, please note that I referred to the end that plugs into the flash, not the PC end. There are some that really look similar but aren't quite compatible. They can be found, but it's a lot easier if you find one with its own original cord.
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Aphototaker
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Posted on Saturday, February 27, 2010 - 04:39 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Mcurrie, I think I have experienced what you describe in the past. I forget which exact flash it was, but it was a Canon speedlite with contacts at the bottom and also a female socket for a PC cord. The socket accommodated a pin and a rectangular strip. The cord I used with that had the corresponding male plug (a round pin and a rectangular strip), but their spacings were a bit off and I had force the cord into that socket to make the flash work. Go figure.

I will keep on eye on this sort of a thing when I buy one.

Thanks.
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Aphototaker
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Posted on Sunday, February 28, 2010 - 09:05 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Just a little update. Ordered a Vivitar 283. Waiting for it in the mail. Apparently, it has "China" written on it and based on my background reading, this should have a safer lower voltage across its hot contact terminals, as opposed to to around 200V in the ones made in Japan (the earlier ones). But I also know that I really to measure the voltage myself to be sure about it. Will get back regarding that when I receive the unit.

Looks to be interesting flash to work on for mods. There are quite few web pages discussing how to add/modify features.
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M_currie
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Posted on Monday, March 01, 2010 - 08:57 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

If my experience with Vivitar flashes is any guide, you'll find that the automatic exposure on your 283 is surprisingly accurate. Using other Vivitars of similar design for years, I find I rarely miss the sophistication of TTL flash. Good luck with it.
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Aphototaker
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Posted on Tuesday, March 09, 2010 - 05:13 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Update to this thread. Received a Vivitar 283 flash. It came with a Canon T-50 camera! :-)

It develops around 11.9~12 volts across its terminals when it is fully charged. During the 'topping up' charges, it drops to around 8.5 V and then back to 11.9 V or so.

It has those lone pin shoe connectors, I suppose the generic ones that work with all flashes.

The flash works on the T-50 it came with. (what a point and shoot SLR camera, btw!)

While mounted on my FTb, it works and I can see the while blinding full rectangle at 1/60 s speed from behind the camera through the aperture. So I suppose the X sync in the camera is working properly.

I mounted the flash in the same way on my AE-1 and it fails to fire. Speed was set to 1/60 s. The flash is supposed to fire with this camera as well, right? If yes, I suppose I need to take the top of the camera off to verify the flash hot shoe wires all okay.

Haven't tried it on my A-1 yet.
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Aphototaker
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Posted on Tuesday, March 09, 2010 - 06:31 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

That was supposed to be AE-1 Program, not AE-1, in my last post. Not sure if this matters.
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Aphototaker
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Posted on Tuesday, March 09, 2010 - 07:23 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Well, I need to correct myself here. It does, in fact, work with the AE-1 Program. I just had to clean the hot shoe contacts a bit.

But there is one odd thing about the PC sync jack that I do not get. I realize that the fundamental working of PC sync connector is closing a circuit when the shutter opens and opening it when it closes. In the FTb, the jack shows continuity as long as the shutter is open. Makes sense. However, in the AE-1 Program, the PC sync continuity starts with the shutter opening and doesn't break till I use the advance lever to wind for the next shot, i.e. the PC contact stays closed from the opening of the shutter till the next advance happens. Is this how it is designed in this camera?
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Rick_oleson
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Posted on Tuesday, March 09, 2010 - 07:41 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

That sort of closed-until-it's-cocked sync was not uncommon back in the days of bulbs - once a bulb was blown it didn't much care whether the terminals stayed closed or not - but I would not have thought you would find it on anything made for electronic flash, certainly not something as modern as an AE1 Program. But I don't have one here to check out.

In the AE1, the PC jack is fed directly by a wire from the hot shoe, so the behavior has no choice but to be identical between the shoe and the plug; I'm not sure if this is the case also with the AE1P, but I would not expect to see any difference in the continuity between these 2 connections.
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Aphototaker
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Posted on Tuesday, March 09, 2010 - 08:50 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I was also a bit surprised to see this long connection. I would been less surprised if it were the other way around, FTb with the longer one and the modern AE-1P with the shorter one. But I am a novice in these sort of things, so ....

I checked oodles of photos I too when I disassembled my AE-1P. I could find only one which shows these wires. In the AE-1 Program, there are three wires going from the body to the chrome top. Two wires, a white one and a green one, go from the flex circuit to the hot shoe. These don't give me continuity (I checked from the top, don't have it opened at this time). A black goes from somewhere within the body to the PC socket, and I believe, from these connects to the hot shoe via a red one. These are shown in the photo below.
Canon AE-1P: wires from the body to the chrom top.

As a comparison, in the A-1, however, I believe that only one wire, a black one, goes from the body to the PC socket, and that connection is then taken (from the PC socket) to the hot shoe.
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Aphototaker
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Posted on Tuesday, March 09, 2010 - 08:58 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

One other observation. I do not get a continuity between the body of the AE-1P and the center (larger round) contact on its hot shoe when the shutter is released (with the flash not mounted, of course). The flash does trigger on shutter release, though, when it is mounted. Is this connection being made by a semi-conductor switch instead of a mechanical one? Or am I missing something else here?

I do get a continuity between similar contacts on the FTb, however.
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Aphototaker
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Posted on Wednesday, March 10, 2010 - 09:50 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I just now checked the Vivitar 283 flash on my A-1. This camera has a wire (black) going from someplace in the body to the center contact of the PC sync socket, and from there to the hot shoe (I presume to the center contact).

The flash works at both place, at the PC socket and on the hot shoe. Max sync speed of 1/60 sec.

The PC socket gives continuity as long as the shutter is open (in contrast to the AE-1P I checked earlier).

I was not able to see any continuity at the hot shoe though (same as in AE-1P).

hmmm ... the premise that the flash is triggered just by making of a metal contact at the hot shoe older film cameras doesn't seem to be right in these case. Can the tinker gurus familiar with these cameras clear my doubts?
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Mikel
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Posted on Wednesday, March 10, 2010 - 11:15 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

"Can the tinker gurus familiar with these cameras clear my doubts?"

Based on your number of posts, you are one of the gurus and we await your article on this subject.
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Aphototaker
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Posted on Wednesday, March 10, 2010 - 11:26 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

oh, no, I am not a guru by any measure. I am a novice tinkerer. If you read my posts, I am sure you will find that most of those are questions. Many have also been called requests for hand holding when I posted with illustrations ... hardly a sign of a guru! :-)

In any case, when I started this thread, it started off with replies stating that flash sync are just metal switches that work in tandem with shutter openings ... in older film cameras (not in modern digital ones). But my observations are not supporting this. So what is presumably taken as a fact, appears to be not so. Now, I am stepping very gingerly with questions and declarations here since I am not an expert in this and it is certainly possible that I am doing something wrong.


I have so far posted what I have seen. I am waiting for confirmation by somebody else before reaching any conclusions.
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David_nebenzahl
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Posted on Wednesday, March 10, 2010 - 11:35 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Don't know for a certainty, but I'm pretty sure that all cameras of the A-1's vintage used mechanical switches for flash, even though they have lots of electronics on board. Think about it: the camera is still a mechanical device, and the flash contacts want to close when the shutter is open, so this is probably going to be accomplished by a pair of contacts closed somewhere in the shutter mechanism.

At this point in this long thread, I've lost track of exactly why you're going through this exercise: is there actually a problem with your camera's flash contacts? Have you tried it with an actual flash unit and not had it work correctly? Or is this just a theoretical exercise?
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Mndean
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Posted on Wednesday, March 10, 2010 - 11:47 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Flash sync in older cameras is a tricky thing, since there had to be sync for flashbulbs, which need an advance in contact to reach full brightness when the shutter is fully open, along with X-sync and so more variables. Some flashbulbs have more lag before reaching full brightness, which is why you see adjustable flash sync on some shutters. Simple cameras with an integral flash system (bulb or X) can get away with a simple contact system since they'll only sync with whatever flash is on the camera. More flexible cameras can't get away with such a simple system. I don't know if that answers part of your question or not.
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Aphototaker
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Posted on Thursday, March 11, 2010 - 12:07 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

David, conceptually you are right. In fact, conceptually it is quite obvious how a flash contact works with respect to the shutter. And to answer your question regarding if there is a problem, please read my recent few posts.

At this point, it is not a theoretical exercise, it is a practical one. I just want to understand what is going on with the basic flash contact on the cameras I mentioned, with the help of people who might know about it.

Mndean, your comments have aided in my understanding the evolution of flashes. Thanks.
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David_nebenzahl
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Posted on Thursday, March 11, 2010 - 12:10 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

But none of that applies to the cameras under discussion here (Canon FTB and AE-1, not the A-1 as I incorrectly stated), which were never intended to use anything except electronic flash, so only have one synchronization method (X-sync).

I just read the part of the manual for the A-1, which might well also apply to the AE-1. Apparently the flash units made to work with this camera (Canon Speedlites) were pretty smart. From the manual:
Except for "B", whatever the shutter speed set, as soon as the pilot lamp of the Speedlite comes on, the A-1 switches to the X synchronization speed of 1/60 sec. -- automatically. The camera's microcomputer controls the light output for perfect automatic exposure within auto working ranges. And just as automatically will the camera switch back to the shutter speed actually set on the dial as soon as the pilot lamps[sic] goes out.

It also alludes to the way the flash is triggered when it describes using flash with the shutter set on "B":
The "B" setting is useful in flash photography for lightening the subject's background. At this setting, the flash of the Speedlite synchronizes with the opening of the first shutter curtain.


So maybe it pays to RTFM, as they say ...
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Donnie_strickland
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Posted on Thursday, March 11, 2010 - 07:59 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Except that's not correct, David; the FTb and the AE-1 both were designed to be used with FP, M, or MF-class flash bulbs, if desired.

On Page 29 of the AE-1 manual, is the shutter speed table for use with flash. For flash bulb use with an AE-1, a shutter speed of 1/30 or slower must be selected.

For flash bulb use with an FTb, it gets even more interesting. Per the Canon manual, for use with FP-class bulbs, any shutter speed except 1/60 may be used. For M or MF class bulbs, it's 1/30 or slower.
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Aphototaker
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Posted on Thursday, March 11, 2010 - 08:10 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Ah, the famous "RTFM" advice! :-)

David:

(I know, you are showing irritates with the length of the thread (why?) but please bear with me, I am just trying to understand stuff here)

I did RTFM. And those paras too. But I was under the impression that the two little pins on the cameras' hot shoes are the ones responsible for such data communication and that the central pin was for the usual dumb make-break connection. Heck, the Vivitar 283 I have does not even have any pins to connect to the two little contacts!

I am not sure why you are saying that "all this" does not apply to AE-1P (or to AE-1, as you wrote)? What is your point? You seem to be implying that these cameras were smart cameras with flashes with digital logic dictating the triggering of the flash. Am I correct?

Further, why are you quoting the second para regarding the "B" speed? Is there any other way the flash is triggered in those cameras other than synchronized with the first curtain?
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Aphototaker
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Posted on Thursday, March 11, 2010 - 10:39 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

So various members here are thinking this thread is going on and on to an off topic direction. Sorry if this appears like this, but it is not so.

Sigh! Let me put all of this into context ... at the risk of blowing all my karma and getting a negative one.

My original query was to see how to know a DIY method to test flash sync in a camera.

I was suggested to get "a damn flash" and see it through the aperture, while being given a lesson that all old cameras employ a metal switch and that the trigger voltage is not an issue.

So I wanted to confirm that.

The basic continuity tests are not showing metal switching contacts. So it might be that there is in fact digital switching. In which case, I shouldn't be using just any flash!

So it all boils down to this. If people are claiming that flash contacts are mere metallic switches, could they please verify it on their cameras (AE-1P, A-1, AE-1)? Any tinkerer worth his salt can do this trivial exercise if he has the camera!

So, no, this is not spinning off to an irrelevant direction. It is unfortunate and sad that such queries are irking some old members here.
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David_nebenzahl
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Posted on Thursday, March 11, 2010 - 11:58 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

@Donnie: Yes, you're right, and I should have read on before I posted that, as even the A-1 manual mentions M and FP flash syncs.

To me, the only thing standing in the way of the OP testing his cameras with flashes, and putting all these questions to rest, is the possibility of damaging the camera. That question has been raised here but not definitively addressed (and unfortunately I cannot shed any light on that subject). My suspicion is that this risk is minimal (and I even wonder how much the warnings printed in the Canon manual against using non-Canon flashes were primarily out of proprietary interest), but I certainly wouldn't want to be responsible for frying one of his Canons ...
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Tom_cheshire
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Posted on Thursday, March 11, 2010 - 12:27 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I think all this camera stuff is like sex. You don't think about it, you just do it.

It is simple, use old flashes with old cameras. Use new flashes with new cameras. Whatever flash was manufactured when the camera was manufactured will work. Would a flash maker make a flash that doesn't work with the available cameras of the day?
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Glenn
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Posted on Thursday, March 11, 2010 - 06:52 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Bloody hell, talk about a little knowledge being dangerous! The A Series Canons were built in the 70s and 80s and such will fire all flash units, from strobes connected to the local high tension supply down to units powered by a piffling AAA battery!! They are not some modern digital wonder that may or may not get fried - depending on what piece of crap you turn up on the web - if you subject them to a few extra electrons.

The A Series do not have M, MF or FP flash contacts. They fire these bulbs via the X contacts, but you will only get proper light coverage if the shutter remains fully open long enough for the bulb to become fully ignited - hence the use of speeds less than 1/60.

If one wants to use the A Series shutter/exposure system to the full under flash conditions, you need a Canon Speedlite or a third party auto-flash fitted with the A series hotshoe adapter.The Speedlites carry the 'logic' circuits that communicate with the cameras via the two extra contacts on the hotshoe.

The black wire on the PC socket of the Program is the earth lead - the top plate is plastic, so how else do you expect to make the return? In the original A1 the PC connections between top and body were spring contacts - no soldered wires to remove. In later versions cost cutting removed the positive contact, replaced with a wire and later even the return was made by a wire.

I suggest that anybody with questions about the guts of the A Series Canons gets the relevant parts and repair manuals - all will be revealed in these documents. If the flash works on the camera then all is OK, don't mess with something that already works properly.
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Mikel
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Posted on Thursday, March 11, 2010 - 08:36 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Glenn, please calm down. We still need you here.

The OP has simply stated that his meter or continuity tester does not seem to behave as the flash that he does not have to test should behave.

And he is still waiting for one of us to explain that inconsistency to him.

He would likely question it as he has questioned almost every answer he been graciously given here. Otherwise, how could this thread have become the longest ever seen on this board to date?

He is not looking to get his camera into operating condition. It is already there. He has been trained in something other than cameras and doesn't have the ability to listen to those who work in cameras but only to recite the questions he was taught to ask in another realm.

That's the reason we have been pushed to the "bloody hell" stage which has rarely been seen here to date.

And for the OP I will pass along my own experience in cameras which can be destroyed by excessive whatever across the flash contacts:

They were all XG series Minoltas.
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Aphototaker
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Posted on Thursday, March 11, 2010 - 08:59 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

er ... Mikel, I *am* listening to what various guys are saying, I have tried all the suggestions that have been given there ... bought a flash, didn't I? I am thankful for all the comments.

However, I am not sure why people here want me to take their claims on faith only!

I realize the thread is getting long, but to pin it on my requests for supporting evidence is just pushing it. I can as well turn around the argument and claim the thread is lacking credible answers and hence furthering the questions.

Can't the claimants just check for the continuity and prove that they are right and end the argument? What is so tough about that?

I honestly do not see why people are being extremely fussy about this almost trivial test. It will bring closure to this discrepancy in a way.


Anyhow, given the surprising abhorrence to long threads here, let me apologize for the questions. No offense was meant to anybody, trust me. And I did call you guys guru tinkerers, but out of respect and appreciation, not to be sarcastic.
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Mikel
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Posted on Thursday, March 11, 2010 - 10:13 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

"However, I am not sure why people here want me to take their claims on faith only! "

Then why in bloody hell would you continue to ask questions of those you have no faith in? What are you up to with that? You seem to want to pursue adversarial relationships to no real camera repair purpose.

None of us have been "extremely fussy" except yourself.

"And I did call you guys guru tinkerers, but out of respect and appreciation, not to be sarcastic."

And I'm not some kind of guru tinkerer but am a retired pensioner of the company that invented the 35mm camera back in the 1920's. Your comment is simply derogatory.

And there are people on this board who likely know more about cameras than I do. Glenn is likely one of them. So is Rick Oleson. The helpfulness is legendary.

I hope that you can resolve all of the camera problems you now face. You have certainly been given more help here than most have required. Once you reach a resolution I hope that you will provide an article detailing your solution for all to read.

Good luck.
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Aphototaker
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Posted on Thursday, March 11, 2010 - 10:37 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Asking questions? ... er... so that somebody can answer them perhaps? You know, somebody other than just *telling* me to stop asking questions? That is one reason forums exist on the internet btw. But I have discovered this there is a very different attitude in this forum.

I continue to ask questions because I have noticed contradictions in the statements given here and what I have observed. To ask for explanations. Is this outside the bound of the topic? I have been very clear and specific in my queries, have I not?

The word "guru" I used was not meant to be derogatory mind you. It was not meant to paint everyone as tinkerer who is not, however, but was addressed to those who are guru tinkerers, in a good way. If you are not, then so be it. But there is no reason to be over sensitive about it! You being so just signifies you are actually looking for reasons to find faults in my every post now.

I am no pro in this field, I do not have many cameras, no relevant experience and just questions. I am not sure how to put it, but this "get off my lawn" attitude is quite unexpected here. People here don't seem to entertain any apologies even!


Sorry for all the noise. I will stop posting here.
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Harryrag
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Posted on Friday, March 12, 2010 - 01:24 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Asking questions is one thing, asking questions the way you prefer is another.
People here usually do not get upset soon, but you almost leave them no other choice. This forum is unparalleled on the net, but it will definitely go down the drain with participants who expect so-called gurus are obliged to give newbies or novices every answer those people hope or expect to get. Everyone is here on a voluntary basis and there is no definite obligation to respond: "members" are not on duty here, on the contrary, they like what they are doing. Your way of moving about in these quarteres is (was?) partly interesting, amusing, entertaining, but also annoying to some degree.
Personally speaking I find it ok if you stay among the posters and do not recede to some secret hideout. Maybe you can accept or try and get used to
the unwritten customs and etiquette pesent among the posteres here, so do not stop posting here, giving up is not a reasonable solution.
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Glenn
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Posted on Friday, March 12, 2010 - 07:46 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Aphototaker,

you are making the fundamental mistake of trying to compare the wiring and circuitry of the AE-1P with the A1. It is bad enough trying to compare wiring on the different production runs of the A1, never mind different A Series models.

The initial X sync switch on the A Series is mechanical, any 'electronic' switching is there purely to control flash output - hence it is built into the Canon Speedlite, not the camera. On face value I do not find your observations on the contacts remaining closed after shutter release odd or questionable. All that will happen, when one attempts to mount a fully charged and switched on flash unit on the uncocked body, is that the charged unit will immediately fire. As a matter of course, one should never attempt to mount active flash units anyway. The fact that you state the flash works on the Program proves nothing is amiss with the wiring to the hotshoe.

As I previously stated, a quick look at the relevant Canon literature would have answered all your questions but I will add the following in the hope that it may clarify the situation somewhat for you.

Taking a basic focal plane shuttered camera that is required to operate an electronic flash unit - The first thing to remember is that the 'sync switch' will operate at ALL shutter speeds; however, only one speed - generally 1/60 for horizontal blinds and 1/125 for vertical blinds - will ensure full frame coverage from the flash output. The 'sync switch' could be a simple micro switch operated by the shutter button, but the double blind configuration of the FP shutter allows greater scope for flash triggering and the 'switch' is actually operated by the blind mechanisms. In the basic configuration the switch is triggered by the release of the first blind or curtain, in more professional orientated cameras the second blind or curtain can also be chosen to trigger the flash. This facility is available on the Canon T90 and is explain in said cameras instruction book.

Just Google first and second curtain flash contacts for more information.
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M_currie
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Posted on Friday, March 12, 2010 - 08:43 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Aphotototaker, a simple question on how you are testing for continuity:

Are you using a digital ohmmeter? If so, then some cameras make their contact at normal sync speed too quickly for the digital meter to respond. Remember that to fire a flash requires only a tiny fraction of a second contact. You simply won't get a reading, not because there is something exotic about the contacts or their operation, but because of the limitations of the meter.

Some cameras will give you a meter reading at very slow shutter speeds, but not as you approach normal sync speed, so if you are just testing to make sure the switch isn't broken, test at 1 second.
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Aphototaker
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Posted on Tuesday, March 23, 2010 - 12:16 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

No more questions in this thread from me, I promise!

TL;DR: The hot shoe was defective. Fixed.

Disclaimer: If you do not like this thread for whatever reasons/preferences you have in your mind, I suggest you do *not* read further. If you don't agree with me or with this thread, remember you are not obliged to reply (unless you have some form of OCD :-)

Okay, folks, I got some time to think about this problem a bit more (Harryrag: I hadn't given up on this problem, only on the tolerance of some rigid readers here). I believe it is appropriate that I close this thread, which brought out so many facets of so many readers here (shudder!! And I thought I had seen my share of topic- and style-nazis* on the internet).

The problem was in the hot shoe of the camera. The little switch that a mounted flash presses was not functioning properly. When I had used a flash with it, it worked, but with the flash off, it didn't. Sometimes, it even failed to fire the flash, as I recently found out. Had to measure the voltage across the flash pins directly to see what was going on (btw, this has important related implications which I will not list here). Working back from there and playing around with the specific part a bit sorted it out.

M_currie: Yes, I was always using longer speeds ( > 2 sec) for this.

Glenn: As you suggested, I found and took a look at the A-1 repair guide. I do not know if you have more documents regarding this, but the one that I have actually has apparently misleading information (if current terminology is to be used). It states that the flash contact goes to an analog switch, which usually means it is a semi-conductor switch! But I tested for that too, and the properties that the contact exhibits do not show it to be a semi-conductor switch.

Now, if only somebody could have verified this with a continuity tester(easy test!), it would have saved all this barrage of criticism and rhetoric here. Oh, and the thread would have been shorter ;)

In conclusion: feels good to put all the doubts at rest to close the case. Given some contradictory advice in this thread, it shows that many readers were not sure about this themselves (possibly didn't even know how the hot shoe really worked). I hope this clears up some confusion.



* http://en.wikipedia.org/wiki/Godwin's_law (*now* the thread is long enough :-)
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M_currie
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Posted on Thursday, March 25, 2010 - 07:54 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

thanks for the followup. Most, if not all, of the cameras I've tested do not have a switch in the hot shoe, but it's a point to remember if one is checking out an unknown camera. I'm a little surprised how few do. It seems a good idea to have this, to avoid the possibility of a shock when using a high-voltage flash on the PC socket.

People use the term "analog" loosely, and these days it's sort of shorthand for anything old-fashioned, so there's a good chance that the manual writer simply choose a poor substitute for the more obvious and informative "mechanical."
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Glenn
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Posted on Thursday, March 25, 2010 - 01:41 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

You must remember that we are talking about 1978 and not the 21st century here, also a translation from Japanese into English. In my original Canon UK 1980 edition of the A1 manual the reference is to 'mechanical' switches, and perusal of the original Japanese documents indicates that in translation the word mechanical would have been used.

Perhaps it's an age thing, but I do not equate 'analog' with semi-conductor switches on cameras of that era.
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Aphototaker
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Posted on Thursday, March 25, 2010 - 03:52 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Glenn: You are probably spot on regarding the mistranslation, since at some other places in camera related literature I recall having encountered "contact" to describe such a switch.

1978 already had digital technology in consumer electronics, though. If you read A-1's service manual, you will find they have used MOSFETs, FETs, op-amps, flipflops, ALU, digital counters, digital memory and all other nifty digital logic based circuits, in other words, a dedicated microprocessor for exposure calculation. Hence my pursuit to determine what they really meant by that phrase.

In comparison, an FTb, however, is a totally different example of belonging to the pre-digital era.

I think Canon adopted digital technology with full enthusiasm with their A-series cameras and and probably with their EF as well (it had semiconductor based voltage regulation!).
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Glenn
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Posted on Thursday, March 25, 2010 - 06:42 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

H.S: I fully agree with your comments about Canon's enthusiasm for the adoption of modern electronic advances in their A Series; however, the real impetus was the fact that the electronics in the AE-1 allowed a reduction of 300 individual parts, allowed automated assembly which all led to a very sophisticated camera at a price that the average amateur could afford. To use a word beloved of modern camera designers, the A1 could truly be described as a 'Bridge Camera', between the classic and modern plastic we all see today.

The only fly in the ointment as far as I see it is that those new fangled Chips were mated with tried and tested mechanicals, that could be seen in the FTb and early F1 series. Nothing wrong in that; the basic shutter and aperture linkage mechanisms are sound designs that have stood the test of time and use and mechanical switches do not have problems dealing with low voltages. The potential for problems to arise was laid when Canon decided that the chips would control the mechanicals by electromagnetic 'switches'. Still the sensitivity of these 'switches' to dirt and grease/oil is easily solved by a simple clean, something that cannot be applied to some of the more electronically advance output of that era from other manufacturers.
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Aphototaker
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Posted on Thursday, March 25, 2010 - 07:05 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

It is interesting to know the numbers regarding the reduction in moving parts.

hmm .. talking of fly in the ointment, I suppose it is sort of a huge leap for the older camera repair person to go from debugging and repairing a mechanical camera to fault diagnosing a digital logic based one. In the latter, a oscilloscope probably becomes mandatory (perhaps even a logic analysis), as a basic tool.
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Glenn
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Posted on Friday, March 26, 2010 - 10:54 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

The reduction in parts count is surprising - not that all of them could be classed as moving, ie brackets and locating plates etc. Depending on your copy of the A1 manual, you may find the oscilloscope listed under basic requirements for fault finding. In fact the later fault finding menus allowed the much simpler expedient of swapping chunks of circuitry - fine if the bits are available but 'up the creek without a paddle' if you are stuck in some backwater with a broken A1 and a very rudimentary repair shop. In 1980 I watched in apprehension as an intrigued Arab repairman in Fez took apart a misbehaving A1. His quest to find out 'how it worked' resulted in him finding the faulty connector that driving over the Saharan sand dunes had vibrated loose. his workshop was little more than a cubical in the Medina, but he had an innate ability to open up that camera and effect a repair.
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Deidrea8
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Posted on Friday, April 09, 2010 - 01:24 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

check out http://www.3eservicesinc.com they have information that you might find helpful
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David_nebenzahl
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Posted on Friday, April 09, 2010 - 03:28 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Diedrea8: So how is a company that offers "industrial electronics repair" supposed to be relevant to this discussion?

DISCLAIMER: I'm not a big meanyhead, and I'm not accusing you of being a spammer. I'm going to assume that you mean well and that you offered this because you thought it would be helpful. But it isn't. This is obviously a company that does repair on industrial electronic systems, not little bitty circuit boards in old cameras.

People might want to think before posting "helpful" hints here, in the interest of not wasting other people's time.

I'm just sayin' ...
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Deidrea8
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Posted on Monday, April 12, 2010 - 08:33 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

ok, i got ya, I just worked with them in the past with electronics and they were informative and great to work with, I just ran across this and admittedly didn't read through everything, I just saw it had to do with a camera needing repair, wasn't sure if they could help. You didn't have to waste too much time to open it and see it wasn't what you wanted. my b.
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David_nebenzahl
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Posted on Monday, April 12, 2010 - 11:55 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

No problemo. Welcome to the forum, and let's hope you post some more useful information in the future.

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