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Edl
Tinkerer
Username: Edl

Post Number: 2
Registered: 01-2009

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Posted on Monday, January 26, 2009 - 08:27 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I found an interesting problem tonight. I pulled out one of my T-90s with a Canon 35-105 3.5-4.5 lens on board. No film in the camera so I fired off a few shutter cycles. The camera was set for its fastest wind speed which is something around 5fps. The camera was firing very slowly, with longer than normal gaps between frames. I set the shutter to 1000 and still the same thing. Yes, shutter priority. I removed the lens and then the shutter would rip em off like it should. Batteries check full power. Just playing now trying to diagnose where the problem is so I remount the lens and move the aperture ring off the A (auto) setting. Fires fast as it should. Did this a few more times back and forth to verify that it fires slow only when the lens is on A, otherwise all is well and it fires fast as it should. So, something is wrong in the lens, I'm guessing with the blades, but they have to move no matter how the aperture is set. So, whats the wisdom on this? How much trouble is it to pull a Canon FD zoom apart? I have 2 more of these lenses so its not really a big deal but I'd like to have it working "just cause".

Ed
Just had a thought, I guess it could be the body having trouble moving the aperture too. I'll have to pull out a different lens and try that. I'd use the other body but it has film in it...
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Edl
Tinkerer
Username: Edl

Post Number: 4
Registered: 01-2009

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Posted on Monday, January 26, 2009 - 11:04 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Hmm, well, this is kind of embarrassing but I found the "problem". I pulled out another lens and tried the shutter tests again. Same problem. I noticed though that if I changed the position of the camera, the point it was aiming too, that the problem would come and go, and it was repeatable. It was acting like the camera was reacting to the light meter except that it was in shutter priority mode...1/1000 shutter speed.. Well, you see the T-90 has this feature called "safety shift" which when turned on, overrides the shutter setting (or aperture if in aperture priority mode) to guard against accidental exposure problems...hmm, yeah, 1/1000 sec. shutter, indoors in the evening, not much light...cameras fine, working just as the talented designers meant it to work...sigh...
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Rick_oleson
Tinkerer
Username: Rick_oleson

Post Number: 779
Registered: 07-2006

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Posted on Tuesday, January 27, 2009 - 03:38 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

curse those designers

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