topic Re: Canon 40d appears to be cropping from the left? in EOS DSLR & Mirrorless Cameras

Canon 40d appears to be cropping from the left?

Rushj — Thu, 09 Mar 2017 08:27:57 GMT

Hi everyone,

I bought this body some years ago and have noticed that I'm not getting the picture I see through the view finder.

For example if I take a centered group shot, the image will be off centre.

It may not be actually cropping but could just be taking an off centre picture to what I'm seeing in the view finder. Usually it appears to crop on the left so I have to shoot wider or more to the left to compensate.

Any ideas? From searches I'm guessing this isn't normal. Thanks

Re: Canon 40d appears to be cropping from the left?

Waddizzle — Thu, 09 Mar 2017 09:06:37 GMT

Assuming your observations are correct, maybe your lens mount is no longer aligned to the image sensor as it should. What could cause something like that to occur? A camera drop. Storing the camera with a lens attached for extended periods of time. The camera body simply warping over time.

If you know how to compensate for it, I say go with the flow. Because it sounds like the only way to fix the problem may be to replace the body shell of your camera, which is not a good option, even if Canon is still repairing the 40D.

Re: Canon 40d appears to be cropping from the left?

Rushj — Thu, 09 Mar 2017 09:24:47 GMT

If say the camera had been dropped by the previous owner (no evidence of this) is it possible the mirrors or sensor is just out of alignment?

Re: Canon 40d appears to be cropping from the left?

Ray-uk — Thu, 09 Mar 2017 11:51:22 GMT

It is almost impossible that the sensor has moved out of position. It is more likely to be a fault with the mirror or focus screen assembly. It could even be the shutter cutting off one side.

Do you get the same problem in live view ?

Re: Canon 40d appears to be cropping from the left?

RobertTheFat — Thu, 09 Mar 2017 17:41:14 GMT

@Rushj wrote:
Hi everyone,

I bought this body some years ago and have noticed that I'm not getting the picture I see through the view finder.

For example if I take a centered group shot, the image will be off centre.

It may not be actually cropping but could just be taking an off centre picture to what I'm seeing in the view finder. Usually it appears to crop on the left so I have to shoot wider or more to the left to compensate.

Any ideas? From searches I'm guessing this isn't normal. Thanks

Do you wear glasses? Then I think I know the answer, because it happens to me if I'm not very careful. Because I can't get my eye close enough to the eyepiece, the angle between my face and the camera matters. Because the right lens of my glasses keeps the camera's left side more distant, I'm effectively looking to the left. Which means I don't see, or take into account, the right-hand end of the frame. In the resulting picture, the subject appears displaced to the left.

Even if you don't wear glasses, your nose could have some of the same effect. Be sure that you're seeing the entire frame.

Re: Canon 40d appears to be cropping from the left?

kvbarkley — Thu, 09 Mar 2017 18:13:20 GMT

I would take a picture of a brick wall with some post-its to provide some reference points to the outside of the image. Then use the center focus point to know *exactly* where the center of the image is and what is shown in the viewfinder.

Re: Canon 40d appears to be cropping from the left?

ebiggs1 — Thu, 09 Mar 2017 21:49:51 GMT

I am going to go with Robert's answer. The other suggestions are impossible and still get you a focused picture. Be more conscious of how you frame and look through the VF.

Re: Canon 40d appears to be cropping from the left?

Ray-uk — Fri, 10 Mar 2017 20:30:44 GMT

RobertThe Fat wrote:

Even if you don't wear glasses, your nose could have some of the same effect. Be sure that you're seeing the entire frame.

Bob
Boston, Massachusetts USA

_________________________________________________________________________________

Ah yes, I remember that happening to me once, but as I now remove my glasses to shoot I had forgotten all about it.

I think you might have found the answer Bob

Re: Canon 40d appears to be cropping from the left?

Rushj — Fri, 10 Mar 2017 23:04:53 GMT

Hi guys, no I don't wear glasses and this is over a long period of time and in every shot.

It's like I lose a fifth of the frame from the left. I.e. Out of alignment. Same on various lenses.

Will try live view as someone suggested though as that would remove the mirror from the situation. If it's ok in live view then it must be the viewfinder alignment/mirror.

Re: Canon 40d appears to be cropping from the left?

Waddizzle — Fri, 10 Mar 2017 23:15:00 GMT

@Rushj wrote:
Hi guys, no I don't wear glasses and this is over a long period of time and in every shot.

It's like I lose a fifth of the frame from the left. I.e. Out of alignment. Same on various lenses.

Will try live view as someone suggested though as that would remove the mirror from the situation. If it's ok in live view then it must be the viewfinder alignment/mirror.

If it is okay in Live View, then there is no misalignment of the lens mount, such as from a camera drop. The issue not showing up in Live View would suggest that your issue is directly related to the viewfinder. It could be your angle of observation. It could be the mirror is misaligned. It could be something else entirely, like the eyecup or something.

How a mirror could be come misaligned is another matter. An attempt to clean the mirror box, without being aware of just how delicate and precisely aligned all of the componenets are is one explanation. The mirror really shouldn't misalign itself without being acted upon by an external force. Then again, hundreds of thousands of shots just might do it, too.

Can you post a shot of the problem?