David
What you have to do is to manually focus, and of course it would be easiest to do this with the lens wide open, and then stop down the aperture to the shooting aperture.
Your Canon should tell you what the correct exposure reading should be, so you can adjust the shutter speed or aperture to get to the recommended exposure or otherwise. It's a bit like using the old all-manual cameras where you would match the needle to get the proper exposure.
It would be a lot easier to focus if you have a split-image focussing screen on your EOS 3, but if you use a 300D or 10D, getting accurate focus is not so easy, as you have to focuss just by looking to see if the image is sharp on the ground glass. If you need critical focus, you may have a problem ... unless you have very good eyes.
Bobby
What you have to do is to manually focus, and of course it would be easiest to do this with the lens wide open, and then stop down the aperture to the shooting aperture.
Your Canon should tell you what the correct exposure reading should be, so you can adjust the shutter speed or aperture to get to the recommended exposure or otherwise. It's a bit like using the old all-manual cameras where you would match the needle to get the proper exposure.
It would be a lot easier to focus if you have a split-image focussing screen on your EOS 3, but if you use a 300D or 10D, getting accurate focus is not so easy, as you have to focuss just by looking to see if the image is sharp on the ground glass. If you need critical focus, you may have a problem ... unless you have very good eyes.
Bobby