I was attempting to capture the full moon tonight using my Canon EOS R50 mounted on a tripod. I had a telephoto lens attached to the camera via a Canon adapter, as this lens was originally designed for my father’s Canon Digital Rebel and had an incompatible mount for the R50.
While zoomed in on the moon to fill the frame, I observed an unexpected behavior: the camera appeared to automatically zoom the image back out. I was under the impression that the camera itself lacked the capability to adjust the zoom setting, but the viewfinder clearly indicated a change in magnification
Update: In case it is important, the lens has image stabilization built in, but I have it turned off as it lets me set focus and recompose better.
I just tried this - Lens is off the camera (and has a lens cover for both ends) sitting looking straight up. I turn zoom ring until the lens is fully extended. I wait a bit then I check for zoom movement and found that the lens was still fully extended.
I don’t know if this is a valid test because sitting on a table - the lens is not getting any electricity from the camera body.
Well the issue can be when it’s tilted up that if you let go of the zoom ring it’s heavy and might slide back from gravity. Laying flat it isn’t fighting gravity heh
I had the lens pointed up. It was sitting on the camera-end cap. I was not holding the zoom ring for this test. It held the zoom for the test and remained fully extended.
Ah I gotcha. Then more likely it’s something focus breathing.