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Mareklew
Tinkerer
Username: Mareklew
Post Number: 79
Registered: 03-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, May 22, 2010 - 10:17 am: | 
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I know, that these lovely XAs are prone to IC sudden death(tm). I also know quite a few floating out there are brain-dead.
As I love my XA and am getting a second one for parts, I'm considering making a replacement electronics board for this camera, experimenting on the parts-donor. But it only makes sense, if I was to order more than one PCB.
Hence the question: is anybody out there interested in a revised, microcontroller based board for their (or their customers') dead XAs?
What would you be ready to invest, assuming, that this solution would alleviate the sudden-death risk completely? I have to consider, if making the boards can pay for itself.
Marek |
Edward8
Tinkerer
Username: Edward8
Post Number: 14
Registered: 03-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, May 26, 2010 - 06:52 am: |
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Hello Merek
I'm a bit surprised that you have not received a reply to your question. The Olympus XA is a modern marvel, a wonderful little camera that I used for many years. It was a back-up for my "serious" Nikons. The XA is a truly great camera, in the right hands.
I am not in a position to help in your endeavor to replicate the circuit board, but I do wish you every success in your project. It is a worthy aim.
Regards. Edward. |
Mareklew
Tinkerer
Username: Mareklew
Post Number: 81
Registered: 03-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, May 26, 2010 - 04:18 pm: |
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Hi, Edward.
I was also surprised by nil interest, as I believed the camera to be quite prone to 'sudden death' of its proprietary heart-IC. Many of them seem to be floating around irreparable because exactly of this reason.
The original circuitry is rather easy to replicate in function, at least with modern electronics. Hardest part is getting the board replaced (mechanically), as it needs relatively deep disassembly.
Such project (design and manufacture of a replacement PCB, development of the circuitry) does make very little sense if done for a single unit though. I hoped for positive resonance here, but it seems I'm gonna mothball the idea for now - at least as long as my XA works with the spares I'm getting.
Marek |
Tom_cheshire
Tinkerer
Username: Tom_cheshire
Post Number: 314
Registered: 04-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, May 26, 2010 - 06:07 pm: |
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The big question is "How much?". It seems easier in today's world to just buy another than to have anything repaired. |
Edward8
Tinkerer
Username: Edward8
Post Number: 15
Registered: 03-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, May 26, 2010 - 09:29 pm: |
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Hi again, Merek.
Sadly, your project is, probably, impractical - which is exactly why I like it! Nothing ventured, nothing gained. May I urge you to keep this idea quietly simmering on the back-burner. Meantime, I'll keep an eye out for brain-dead XAs ...
Tom cheshire:
It is certainly incumbent upon all of us to be fiscally responsible and one does one's best, but may I pose a couple of questions?
When America plonked a couple of blokes on the Moon, did anyone quibble about money?
When Hilary mounted Everest, did he have an accountant is tow?
When J. Slocum sailed the world in his ketch, did he have a banker on board?
When Alec the Great - or was it Vlad the Impaler? - used elephants to tromp over the Alps, did anyone think he was mad?
Some things just have to be done ... like pure science. And string theory and quantum mechanics ... and resurrecting dead XAs.
Cheers. Edward. |
Mareklew
Tinkerer
Username: Mareklew
Post Number: 82
Registered: 03-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, May 27, 2010 - 03:39 am: |
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Tom:
The easy way out, which you suggest, is less and less available. Out of three XAs that passed by now through my hands, three had aged CdS cells, i.e. less responsive to light than they should be, and with curved characteristics.
My best-shape XA had to be adjusted by 2 stops and yet, it can't be trimmed exactly right - the exposure controlling cell aged and has a gamma of about 0.8-0.9 instead of close to 1.0, which in practice means, that fast shutter times run a stop slower than slow shutter times (adjusted to give perfect 1/125s will expose at 1/2s when it should at 1s, or adjusted for good 1s will give 1/60s at 1/125). This can be tricked out with some compensating resistors (not present in Olympus design), but is an indication, that the CdS oxidized and is dying. Actually the repair manual says, that if you can't get the speeds right, you are to replace the CdS (or fix the mechanics if that's the culprit).
As to 'how much': that's why I ask, if there's a demand. For one board it will be expensive. For 10 - not so.
The thing is, that upgraded design can upgrade functionality too. One thing I want to have is user-adjustable shutter speed limiter - "don't expose longer than 1/xxs". It could also be possible to provide basic "EXIF" (okay, aperture remains unknown, but timestamp and shutter speed can be done).
Marek |
Tom_cheshire
Tinkerer
Username: Tom_cheshire
Post Number: 315
Registered: 04-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, May 27, 2010 - 04:56 am: |
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Ed.8: I say why string theory? Go beyond that to rubber band theory.  Hmm, I never realized fixing old cameras was a historical landmark event. I sometimes feel that way when using them though.
Mar.: I can get around all those problems by shooting a good wide latitude color or B/W print film that still produces good results even when exposure is "off" by 3 stops more/less.
But your statement has opened up a wider question for me. If CDS cells "age" into inaccuracy on an XA then it must be so for all cameras. Ergo, all these people who are using their Minolta 7s, Yashica Electro, Olympus OM1, etc. must be getting inaccurate readings or something like that. Hmm, now you got me thinking the same extends to older light meters like the Luna Pro, etc.
Well, this doesn't bother me so much because my "philosophy" is to use cameras without meters or not meter dependent.
A funny image just entered my thoughts: a guy screaming in the face of another guy that his gamma is all off and the other guy, holding his classic box brownie, showing off his nicely exposed photos. |
Mareklew
Tinkerer
Username: Mareklew
Post Number: 83
Registered: 03-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, May 27, 2010 - 08:39 am: |
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Tom:
As to aging of CdS Cells: your conclusion is (fortunately) false. These cells do not 'inherently' age (like e.g. rubber or foam) to an noticeable extent. Similarly to selenium cells longevity of a CdS cell depends on its environmental sealing (it's just much, much easier to seal a CdS cell). Many meters, like LunaSix, use cells that are nicely encapsulated in metal-and-glass housing. These are virtually aging-free. Unfortunately XA cells are simply painted over with some clear lacquer - I guess it's mainly due to available space limit. This works well for quite a long time, but fails at some point due to exposure to humidity, UV etc. damaging the lacquer. It is similar to what ate most of the old selenium cells - ones, that were sealed well keep going to this day, as selenium does not deteriorate inherently, but ones that had only some lacquer to keep oxygen at bay are mostly gone by now.
I know, that I may pretty much ignore my meter being off by 1 stop, and this only at shutter speeds I don't shoot at anyway. But it is not the point. As it is now 2 stops away from where it was initially, it suggests the sealing is gone and further degradation may progress fast. Interesting is, that BOTH cells in my XA aged almost IDENTICALLY (from the electric side), which suggests something systematic. Google set loose on the topic yields quite many results of similar problems: cameras metering is more-or-less OK in low light, but indicated shutter speed being reluctant to rise over about 1/60s. If inspected, shutter runs slow overexposing by a stop or two (which not necessarily must be apparent to the user due to print film latitude, hence many state, that 'needle is off, ignore it, it still takes nice photos').
I don't usually fix what ain't broken. However, having a parts camera, that has all the shutter assy in order, but dead electronics, is kinda teasing to get the actually broken stuff fixed...
Marek
BTW: might you tell me, which B/W print film tolerates underexposure by 3 stops? |
M_currie
Tinkerer
Username: M_currie
Post Number: 230
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, May 28, 2010 - 09:32 pm: |
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I bought one XA a few years ago with non working electronics, and have had an XA2 and an XA3 both die of the same microprocessor fault - no firing except with self-timer. But whenever I see one cheap, I grab it. I have a couple of working XA's and three working XA2's, so I'm pretty well set for the foreseeable future. So far I've not noticed any deterioration of the meter cells.
But I wish you luck with your project. |
Tom_cheshire
Tinkerer
Username: Tom_cheshire
Post Number: 318
Registered: 04-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, May 29, 2010 - 03:58 am: |
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That is something of a relief to know that "CDS aging" does not affect all cameras, etc. In time, all things wear out or deteriorate into uselessness so it is a case of use it while you got it.
The reference to "3 stops over/under exposure" referred mostly to color film but I have heard good things about some Ilford B/W films.
I have an XA and it seems to work well but the problem it has is the "cover" does not fully retract away from the little RF window. It sticks partly over the window but there is enough superimposed image to still use it so I haven't tried to fix it. Also have an XA1 with dead meter cell.
M_Currie echoed my comment of buying up working units, using, tossing and replacing which seems to be the mainline thinking these days.
I think there are many people who would want the item you are proposing but this forum is too small and limited audience for proper feedback.
My advice is to get a good business plan of what it will cost to build these items and send "feelers" out to sellers like Micro Tools, etc., to see how many they will buy, etc. |
Edward8
Tinkerer
Username: Edward8
Post Number: 24
Registered: 03-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, June 07, 2010 - 10:36 pm: |
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Marek:
I'm probably the only person left on the planet who retains faith in your project.
And this is a long shot, but I throw it into the mix for consideration.
In my experience, if there is a problem - go to the top. In this case, Olympus, Japan. Appeal to The Chairman. In correct Japanese - NOT a Google translation - explain your project. About 12 tight paragraphs would suffice.
The Japanese are a proud people. The Olympus company should be justly proud of producing one of the hallmark cameras of the 20th Century.
Surely, Olympus has a small niche in the lab set aside for public relations - and a spare bloke with a soldering iron and access to appropriate chips!
Some cameras deserve a genteel, dignified death. So be it. The Olympus XA CAN be revived, to lead a long and productive life. One never knows until one tries: Who knows? Maybe Olympus can find a PR hook to facilitate small-scale funding?
Or, as they say around here, am I pushing shite uphill?
Edward. |
Mareklew
Tinkerer
Username: Mareklew
Post Number: 91
Registered: 03-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, June 08, 2010 - 01:14 am: |
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Edward, thanks for your words of reassure.
In desperate doubt, I'd go to Olympus, but there's no such need. I respect their engineers and their time, especially, that they have produced a repair manual with not only if-then troubleshooting, but also with an extensive description of camera function and the logic and sequences behind. I believe this is enough not only to re-engineer the circuit, but also to copy the original...
As for now I have my parts camera, revived my old XA with parts from it and am working on a breadboard prototype - the shutter fires, that's something already. Pity, that the parts camera has a shot viewfinder glass and damaged shutter speed indicator (still takes photos though, so perfect for such scrap project).
Marek |
Edward8
Tinkerer
Username: Edward8
Post Number: 27
Registered: 03-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, June 08, 2010 - 02:11 am: |
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All the best. Don't give up, Merek.
This is not a threat, but I have no wish to visit your place of abode to administer words of a harsh nature ... and several bottles of good red wine.
Regards for now. Edward |
Vinzenz
Tinkerer
Username: Vinzenz
Post Number: 31
Registered: 06-2008
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, June 14, 2010 - 08:30 am: |
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I have a rather battered but working XA and a nice looking XA whose shutters stays open for about ten seconds at all speeds and flash sync. The meter needle shows the correct shutter speed. With the back open the camera releases correctly at 1/60. I was told that this might be caused by a split in the ceramic disc to the right of the lens.
I looked into the camera but could not find the fault up to now. Could a replacement of the circuit possibly help in this case? I would then be a candidate on Merek's list. |
Mareklew
Tinkerer
Username: Mareklew
Post Number: 99
Registered: 03-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, June 14, 2010 - 08:59 am: |
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The behavior you describe can be also a compound of two faults. The exposure metering cell is connected to the circuit by a piece of wire. If it failed you get long exposures at all settings EXCEPT the flash. BUT the flash "mode" activating switch is also prone to failure, so you might have not noticed that it (separately and independently) stopped functioning some time ago and discovered it first now, when looking at the more apparent fault.
Actually I have not noticed that my old XA has the flash switch problem till recently, as I almost never used flash (if this switch fails, flash pops up and releases as normal, just shutter speed is at 'measured light -2EV', which, with 400 film, may still be reasonably short even under indoor conditions).
Marek |
Vinzenz
Tinkerer
Username: Vinzenz
Post Number: 33
Registered: 06-2008
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, June 14, 2010 - 09:23 am: |
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Thanks for the quick reply, Marek.
I have just made another test in bright sunlight. The flash goes off, but the shutter stays open for ten seconds. The only way to get a faster shutter speed is to release the camera with the lens slide shut and the back open. I guess this is due to a mechanical shutter speed.
If you could give me any advice how to find the fault, I would be grateful. The self-timer switch in the bottom of the camera and the magnets seem to work properly. |
Mareklew
Tinkerer
Username: Mareklew
Post Number: 101
Registered: 03-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, June 16, 2010 - 02:11 am: |
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As I said, it's either damage to the PCB, or failure of two elements: cds connection and flash mode switch. As failure of flash mode switch can pass unnoticed for quite a time, so the second option (two failures) is not automatically less probable than the first one (a single failure).
Unfortunately to diagnose/repair it you need to disassemble most of the camera, which is not necessarily easy to rebuild. Try reading the repair manual from download section of this page - if you can't follow it, I'd suggest not attempting this repair yourself (the camera is compact and mechanically more puzzling than the manual).
Marek |
Msiegel
Tinkerer
Username: Msiegel
Post Number: 187
Registered: 03-2008
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, June 18, 2010 - 01:48 am: |
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Vinzenz,
I can confirm that with the back open and the slider shut the camera is set to "film loading mode" meaning the electronics are overridden to enable releasing the shutter and wind on while having a look if the film loads OK.
Not much help - sorry. |
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