Canon EF 75-300mm III to Canon Rebel T5

[zjasani]

Hi,

I picked up a used T5 with the 18-55 mm kit lens and also the 75-300 mm. I can't attach the 75-300mm lens to the camera for some reason. I place the lens into the opening and match the red dots for the EF lens. The issue is, I can't twist to lock it into place. I've applied some force to it thinking maybe it just needs an extra push but I am also scared to damage the lens. Does it need just a little extra force or any ways to identify and fix what could be the issue? Maybe the issue is not the lens and is the body?

Thanks,

[busyretired · Accepted solution]

If other lenses work with the body your 75-300 may have slight mount damage that isn't easy to spot.

Mount tolerances are so tight that a very small tweak will make a poor fit.

[kvbarkley]

It should just work. I have no problems with my EF lenses. I can't tell the difference between an EF and EF-S lens. Before applying more force look at the lens and mount carefully. While there are features on EF-S lenses to keep them from mounting on an EF mount, it does not work the other way.

[zjasani]

The lens fits into the opening just fine so I guess its mounting it just won't lock into place. I've tried holding down the release when twisting too but that hasn't helped.

[busyretired · Accepted solution]

If other lenses work with the body your 75-300 may have slight mount damage that isn't easy to spot.

Mount tolerances are so tight that a very small tweak will make a poor fit.

[ebiggs1 · Accepted solution]

"Does it need just a little extra force or any ways to identify and fix what could be the issue?"

It needs very little force, exactly like mounting your 18-55. I assume it mounts OK? The mount may be broken but it would tale a significant blow to bend it.  Enough that the lens itself would probably be damaged too. This lens is not a good candidate for repair either. But a call to Canon will comfirm that or not. 1 (800) 652-2666

[zjasani]

Thank you @busyretired @ebiggs1 I took it to a local repair shop and they were able to find some damage. The mount had a portion that was “sticking out” that caused the blockage. The shop said they could try filing it down but probably won’t work.