New canon 300mm f2.8 separated from body...

I just got a new Mark III recently and have been using a 400mm DO with it and have had no problems. Yesterday I got a new 300mm f2.8 and went for a shoot this morning. About 5 minutes into it while holding the body with my right hand and the lens by the foot with my left...the two separated while I was taking some shots. Luckily my grip on the lens foot became a death grip and I saved it from going into the drink at Green Cay Wetlands (Florida). My father was with me and he said maybe I didn't have it locked in right...but I am very meticulous about those kinds of things so I was sure I did. Well we kept walking with me now cradling my lens and camera like a new born baby. A few minutes went by and I wanted to shoot an egret and it's reflection and was going to change the drive to 'one shot' and saw that I couldn't. I also noticed my f-stop showed '00'. I turned the camera off and back on and it was the same so I was going to take the battery out and put it back in and suddenly the lens and camera were not completely apart but freely moving toward separation again. Both within about 10 minutes! After it happening the first time I locked it in place and spent a couple of minutes gently twisting and turning to see if it was going to happen again but it felt solid.

Has this happened to anyone else? Anyone heard of it?

Thanks much!

Matt

You were lucky Matt. Check that the locking pin on the body is working properly. You probably know this but the little click you hear when the lens is turned clockwise to the limit is the pin finding its hole in the lens mount.

Were you somehow operating the locking pin release on the body without knowing it?

I use the 500/4 on a 50D and 5D and have never seen anything even close to this.

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Has this happened to anyone else? Anyone heard of it?

Thanks much!

YES, it happened to me last year with they same combo...& afterward I had 00 & focus locked.

I send both body & lens to canon repair...

I sold the body & still have the lens and never had any problems with that lens on the 50D or 5D since

Hey John,

It is working correctly and I checked it so many times while walking with my dad on the boardwalk before it happened a second time. I have been doing some testing in my back yard and there is no physical way I could release the lens via the button on the body.

I spoke with Canon and they suggested I put the lens on another body and see what happens. I did and nothing was out of the ordinary. I also put my 400mm on the Mark III and the same...perfect. I then switched back to the 300mm on the Mark III and no problem after a hundred or so pictures.

I'm not sure what happened but it's got me spooked for sure!

On an EOS-3, I once had a pin that failed to lock occasionally (i.e., the pin stuck in the down positon). Once locked, I can't imagine the pin retracting on its own, so if you remember to check every time you put a lens on the body, you should be OK.

With converters I used to have that problem, had to make sure they locked !!!

Fortunately I am one of those quadruple checkers and they were locked for sure both times. I spoke with Canon again and they suggested I return both the 300mm and Mark III (just in case it was the new Mark III) to the dealer I got them from. After speaking with the dealer they said no problem they will ship me new ones so they went back this afternoon.

Thanks for the help and advice!

Quote:

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Originally Posted by Alfred Forns

With converters I used to have that problem, had to make sure they locked !!!

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I always send the convert with such a problem to get fixed--and stop using it immediately because I know when I am rushing I will forget to make sure it is locked. I remember one of Artie's DeSoto IPTs where someone had a new camera go in the salt water when they forgot.....