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Canon Rebel T7 will not auto focus 300 MM lens or take pictures

rchrderb
Apprentice

The camera worked great. I followed the instructions to set it up. I used it mostly for sports photos for my kids.  I recently used it, no issue. Next time i went to use it the auto focus feature the camera would not work or take any pictures when I turned the lens from 75 mm.  it will only auto focus and take pics with that lens setting, trying to zoom in for close ups doesnt work

3 REPLIES 3

jrhoffman75
Legend
Legend

Any subject or just certain ones? Are you using all focus points or just one?

The AF system needs sufficient light and contrast to focus on (think edges between light and dark).

As you zoom in you might be filling the screen with a subject and thus not be providing edges for the focusing system to latch on to.

John Hoffman
Conway, NH

1D X Mark III, Many lenses, Pixma PRO-100, Pixma TR8620a, LR Classic

Greetings, rchrderb

jrhoffman75 has provided great questions regarding the issue you're experiencing. Please proceed to test the camera and lens in a well lit environment and to focus on a subject with good contrast.

If possible, please also test a different Canon zoom lens to see if the camera will auto focus within its focal range since it appears that your current lens is only able to focus when it's at 75mm. This will help determine if the issue is related to the lens itself.

Isac789
Contributor

The first thing to check when your camera’s auto focus fails, is that you have your DSLR lens set on AF (auto focus) and not MF (Manual Focus). This may seem obvious, however there have been many times when I’ve used manual focus and forgot to change it back to auto focus when required. If you are able to switch between AF and MF, you will find the switch for this on the side of your actual lens.


@Myhdfs Account Login wrote:

The camera worked great. I followed the instructions to set it up. I used it mostly for sports photos for my kids.  I recently used it, no issue. Next time i went to use it the auto focus feature the camera would not work or take any pictures when I turned the lens from 75 mm.  it will only auto focus and take pics with that lens setting, trying to zoom in for close ups doesnt work




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