CANON A-1 troubles --

pentaxpete

pentaxpete

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Peter
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I'm devastated -- my lovely 'Gift' A-1 is now letting me down when I use it with ambient light -- all exposures are about 5 times OVER-Exposed -- I did a Kodak T-max 400 and all were black on processing in ID11 1+1 -- I have de-sqeaked it about a year ago -- do you think some of the oil had got into an exposure circuit board -- no sign of oil when I took off the base-plate though ?
Today I did another test with 1991 dated Ilford FP4 film -- I set 100 ASA as it was old then did a series of 'Auto' exposures : 'P','AV,'TV, and I got 1/125 @ f6.7 on 'P' and 1/1000 @ f2.5 on the others which agreed with a Sekonic Spotmeter reading for 1/1000 -- so I took another on 'Manual' exposure with the lens OFF the Green 'A' and set 1/1000 @ f2.5 and ALL were over -exposed -- I also took a series with my Canon Speedlite 199A set to 'auto' first then set to 'manual 1/60 ' on shutter and they ALL were the SAME density OK -- just the daylight ones are over-exposed .
It look as if the faster speeds are running very slow as one I took on the Kodak T-max 400 with the Canon 200mm f4 SSC lens was over-exposed but also had camera-shake although I had set 1/1000 sec speed.
 
Maybe the electro magnets? (the most likely)
You would have to take the bottom of the camera off. The faces of the magnets can get covered in gunk after 20 to 30 years :)
I assume you have tried a new battery. Google 'canon A1 shutter magnet' on images to see what they look like. They have a plastic cover that can be prised off.
Canon A1 repair manual pdf
Another option- it might be the shutter speed dial, or catastrophically, the circuit. Only remedy would be a new body, they're pretty cheap just now.
 
Thanks -- I will take off the base-plate again -- I have SEEN a little plastic cover -- that must be the one you mention - there is no sign of excess lubrication from the Canon Squeak lube I did.
 
I took off base-plate again and cannot see any corrosion on the electro-magnet or the exposed soldered circuit -- I tried the shutter speeds again -- all the 'slower' speeds are accurate even the 15 seconds is 15 seconds -- it;s just the faster speeds must be running slow.
 
Have you tried the exposure compensation?
It may be that the ISO dial is corroded, this was a typical problem with Yashicas of the same vintage.
The other setting to try is B, just to see what happens.
 
Just a thought, I assume that the stop down lever in the mount opening for the aperture is working properly?
 
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Just had another test with some outdated Kodak T-max P3200 dated 06/89 from my fridge : well, I tried all the shutter speeds outdoors down to 1/30 and ran out of apertures so went indoors on a different subject by window light and went down to 1/2 sec before running out of apertures at f22, then I set the Canon 199A Speedlite up again and set 'auto' and although shutter was on 1/250 it read '1/60th' in viewfinder when flash was charged > I rated film at 250 ASA and processed in home-made ID11 1+1 and results were better : after excercising shutter many times with , camera empty -- the 1/1000 and 1/500 are still only 'slightly denser' than the rest which indicates running slow but not as bad as before -- the flash exposures were all 'even' so no troubles there - maybe I should avoid using 1/1000 and 1/500 OR set a higher film speed if I use those two shutter speeds.
 
Isn't there a tungsten cable that if broken, can cause this type of issue? I'm no expert, but did have some metering issues with my AE1-P which seemed to cure itself with a little movement of the ASA dial. Luckily I mine wasn't broken, but the dial wasn't seated correctly. Might be worth a try, although not sure how the AE1-P differs the the A1 :thinking:
 
I have taken off the base-plate several times and looked with a good light and magnifier but cannot see any 'broken connections'.
 
That is why I have not seen it then -- I am not venturing into taking off top of camera !
 
pentaxpete said:
That is why I have not seen it then -- I am not venturing into taking off top of camera !
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Contaxes are prone to this. The copper contacts under the ASA setting dial are prone to corrosion. People tend to use the same ASA film so the dial doesn't get moved much.
A quick fix is moving the dial back and forwards to try to clean the surfaces.
 
That American Bloke I follow ' Fix Old Cameras' always says use 'Isopropyl Alcohol' for everything but you try to GET some in England -- I went round every Pharmacy and BOOTS in Brentwood -- the girl in BOOTS had not heard of it even !! -- Others said " You need a special LICENCE to get it " I do not have those JIS screwdrivers or that special pointed wrench tool he uses. RE turning ASA dial -- that is similar to a 'Tip' on the Pentax ME Super i found out -- went to USA once with the PhotoTravelleers Group and my ME Super readings were giving me 1/2000 at f16 -- a stupid reading !! So I was told to turn the Exposure Compensation dial back and forth several times and it cleaned contacts underneath and i got better readings for 100 ASA of 1/250 @ f11 in bright sun as it should be !
 
pentaxpete said:
That American Bloke I follow ' Fix Old Cameras' always says use 'Isopropyl Alcohol' for everything but you try to GET some in England -- I went round every Pharmacy and BOOTS in Brentwood -- the girl in BOOTS had not heard of it even !! -- Others said " You need a special LICENCE to get it " I do not have those JIS screwdrivers or that special pointed wrench tool he uses. RE turning ASA dial -- that is similar to a 'Tip' on the Pentax ME Super i found out -- went to USA once with the PhotoTravelleers Group and my ME Super readings were giving me 1/2000 at f16 -- a stupid reading !! So I was told to turn the Exposure Compensation dial back and forth several times and it cleaned contacts underneath and i got better readings for 100 ASA of 1/250 @ f11 in bright sun as it should be !
Click to expand...

Try this http://www.amazon.co.uk/500ml-Isopr...=1426587172&sr=8-2&keywords=alcohol+isopropyl or just buy some make up remover from boots or superdrug, it's all much of a muchness
 
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