Avoiding lens slipping off camera? 40-150 f2.8 came off today...

Hi,

First off, so sorry for your situation. I get how you want your lens to look its best at all times, especially some slick glass like the 40-150 2.8 pro.

Secondly, though, I really think you're being a bit superficial about this. You mentioned some minor cosmetic damage. If you had the hood deployed when it slipped, I would expect the hood to take most of the damage. At that point, the lens barrel probably has a few dents and scratches, but as long as the glass functions properly and creates a sharp image, I really don't see why you would have to sell it off. Of course, if you want to, that's your right. You'll be losing money unnecessarily on a great lens that still functions, but that's your choice.

Finally, what I found is that when a lens is locked onto the mount, the button will have a bit of resistance due to friction of the lock against the lens mount. You'll probably be able to feel a slight jerk if you accidentally pressed the button. Furthermore, the lens mount and camera mount will have quite a bit of friction, so it should't have been that easy to knock it off. Have you been using the lens for a while? After prolonged use the mount may have worn off a bit, reducing the friction, making it easier to push off.

I would suggest you simply check the lens once in a while to ensure it's locked on tight. As you said, you care deeply about the cosmetic of your camera set up, so anything you add onto the camera to increase the hold on the lens will take away from the design (i.e. putting gaffers tape around the mount and barrel to prevent it sliding off).

The 40-150mm f/2.8 Pro has a tripod collar, so while holding it you should be able to tell if it's in the right position on the mount and not about to fall off. If your tripod collar is positioned downwards, then while holding the lens the tripod collar should always be resting in your palm.