Canon A-1 Aperture Priority Mode

[nicholas_acuna]

<p>I suspect that my Canon A-1 is not functioning correctly in Aperture Priority mode, but I don't know enough about this camera to be sure.</p>

<p>If I set my A-1 in Shutter Priority(Tv) mode and select the shutter speed I want on the dial, the exposure preview LED in the viewfinder will display that shutter speed and adjust the aperture automatically, as it should. If I set my A-1 to Aperture Priority (Av) mode and select the aperture I want on the dial, the exposure preview LED in the viewfinder does not adjust the shutter speed automatically. The camera won't lock the selected aperture in the exposure preview LED, but instead the camera continues to work as if it was in Tv mode. It seems that the camera does not recognize that I have switched to Av, and any adjustment I make to the dial will only change the shutter speed. If I set the Av dial to F1.4 the exposure preview will display the shutter speed as locked at 30" (which is the Tv equivalent on the dial), the same applies to every other Av setting (it will only recognize the equivalent Tv setting on the dial).</p>

<p>This is not a huge deal since I only use this camera for casual hobby photography, I can still control aperture on-the-fly a little bit by varying the shutter speed (or by using full manual settings). I still enjoy shooting with this camera, but if I can get it back to 100% working order I'd like to do that. How can I fix this issue?</p>

<p>-Nick</p>

[SCL]

<p>It has been a long time since I had an A-1, but I remember occasionally having issues somewhat like you describe. In most cases for me it was making sure the auto diaphragm on the lens was properly engaged and that the lens was snugly placed on the camera body. A little jiggling here and there seemed to fix things for me.</p>

[nicholas_acuna]

<p>Thank you for the response, Stephen. How can I check that the auto diaphragm on the lens is properly engaging? I'm not familiar with some of the inner workings of the camera. </p>

<p>This might be unrelated: I can't get the aperture blades to move when the lens is mounted. Using the aperture ring on the lens, using the stop-down lever, I can never see the aperture blades moving. The pictures I have taken seem to come out OK, so I'm not sure if this is normal. I was trying to see if the lens aperture was stuck by cycling through the different f-numbers and watching the blades open or close accordingly. If I take the lens off I can manually operate the aperture, but with the lens on the camera I can't.</p>

[PapaTango]

<p>Nicholas, do you have another lens that you can mount and see if this behavior is consistent--or just a product of a single lens?</p>

[nicholas_acuna]

<p>Patrick, I have two 50mm F1.8 lenses (bought a second one on a whim thinking the first one was broken), the camera behaves the same regardless of which lens is mounted. I have a 28mm in storage that I haven't tried, I'll give that one a shot tonight and see if it makes any difference.</p>

[paul_wheatland]

<p>Position the lever to AV mode. Open back door to camera body, click the shutter with advance lever and fire the camera while looking at the back of the lens to see if iris stops down for the exposure! Hope this helps to determine proper action. Next try it at noted shutter speed at TV setting too observe if iris diaphragm is same size.</p>

[paul_wheatland]

<p>Position the lever to AV mode. Open back door to camera body, cock the shutter with advance lever and fire the camera while looking at the back of the lens to see if iris stops down for the exposure! Hope this helps to determine proper action. Next try it at noted shutter speed at TV setting too observe if iris diaphragm is same size.</p>

[SCL]

<p>+1 what Paul said. When the lens is mounted, the blades will remain open until you fire the shutter. By design, when dismounted from the body the blades will remain partially open until you attach a rear lens cap or unless you have a special cap which opens them fully.</p>

[awahlster]

<p>READ THE MANUAL</p>

[mwmcbroom]

<p>The A-1 is a little quirky in this respect. When you're in Aperture Priority mode, your lens must still be set to the "A" setting. The A-1's aperture is controlled by the Av dial, not by the aperture ring, the way it is with other Aperture-Priority cameras.</p>

<p>The way you have your camera set, it thinks its still in Manual mode. In fact, Manual is the only time you want to move the aperture ring away from the "A" setting. In all other exposure modes, just leave it set to "A".</p>

<p> </p>