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Finnegan
Tinkerer
Username: Finnegan
Post Number: 97
Registered: 09-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, November 22, 2011 - 11:14 am: | 
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Does anyone have advice on how to test for vibration? I have two Sears slrs that, with the lens off, make a really loud noise when shot. They are functioning properly but I am amazed at how loud these particular shutters are (Copal type) compared to my Chinon slrs and all the others. It got me thinking about vibration and how to test for it, etc. |
Donnie_strickland
Tinkerer
Username: Donnie_strickland
Post Number: 139
Registered: 09-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, November 22, 2011 - 11:56 am: |
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Which models are they? |
Finnegan
Tinkerer
Username: Finnegan
Post Number: 98
Registered: 09-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, November 22, 2011 - 04:53 pm: |
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Sears KS500. Going to sell them. |
Mr_flibble
Tinkerer
Username: Mr_flibble
Post Number: 20
Registered: 10-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, November 23, 2011 - 02:06 am: |
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Does the noise originate from the mirror or the shutter itself?
I'm not familiar with these cameras to be honest. Do they have foam mirror cushions installed? |
Cooltouch
Tinkerer
Username: Cooltouch
Post Number: 153
Registered: 01-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, November 23, 2011 - 02:37 am: |
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You can try standing a nickel edgewise on a top flat area of the camera(s) and then trip it with a shutter release. Think I saw a Hasselblad ad years ago where they did this. So if the vibration doesn't knock the nickel over, I reckon the shutters are just loud.
All the original Canon F-1s I've owned make a loud "pop" when the shutter is fired with the back open. I've always thought it was a cool sound, and never worried about vibration, which I don't think those cameras have much of anyway. Seems to me though that if the vibration was excessive, you should be able to feel it as well as hear it. And if you're not feeling it, it's probably nothing to be worried over. |
Marco
Tinkerer
Username: Marco
Post Number: 23
Registered: 10-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, November 23, 2011 - 09:09 am: |
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Knock a nickel over? I can flip one over whilst testing any of my Praktica BCs for vibration! |
Hanskerensky
Tinkerer
Username: Hanskerensky
Post Number: 136
Registered: 05-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, November 23, 2011 - 12:26 pm: |
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The best test is of course by making photos of a a piece of black cardboard with a pinhole and a lamplight shining through that pinhole. Study the exposed and developed film with a magnifyer or projector and see how the image of the pinhole light looks (nice point, not so nice weaves).
In this way you can determine the effects of vibrations at the moment it matters, when the photo is taken.
Another less exact way is (please don't smile) to place a wide glass partially filled with water on top of the camera and study the waves when you trip the shutter. DON'T TRY THIS WITH A FULL GLASS ;-) |
Finnegan
Tinkerer
Username: Finnegan
Post Number: 99
Registered: 09-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, November 23, 2011 - 12:28 pm: |
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The KS-500 is a very basic all manual slr with 1/8th to 1/500th. It has the standard foam for vibration dampening. The noise is from the mirror mechanism mostly. It is a loud "clang" and after it shoots you can still hear an echo like when you hit metal and it keeps "singing" afterwards. I thought about the coin balancing on the camera technique but then thought everyone would tell me that was for tuning a '52 Chevy.  |
Mr_flibble
Tinkerer
Username: Mr_flibble
Post Number: 21
Registered: 10-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, November 24, 2011 - 02:08 am: |
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I also use the coin-on-its-side trick to tune the Go-Devil engine on my '43 Willys MB
Both my Praktica MTL-50 SLRs have the same loud report when the mirror claps up. But I have seen, to my untrained eyes, no evidence of noise or vibrations influencing the actual photos. |
Glenn
Tinkerer
Username: Glenn
Post Number: 962
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, November 24, 2011 - 05:39 am: |
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Oh dear, idle minds and hands springs to mind here! The only things likely to blur the images are the photographer's stance and poor grasp of the camera. Only in very specific cases - time exposures of a certain critical length, with the camera mounted on a particularly flimsy tripod - will you be able to detect image blurring due to internal vibration, and then only by examining the the negatives under high magnification.
A good dose of fresh air and a pocket full of film is the best cure for this imagined complaint. |
