Lens to Body Play, how much is too much ?

Santa was very good to me this Christmas,
He left a new 70D and 100-400 L under the tree !

Since I'm brand new and need new things to fret over I ask about tolerances.

The lens seems to fit well and snaps onto the body crisply. It doesn't feel loose in any way with slight vertical or horizontal manipulation however the lens does rotate ever so slightly with clockwise and anti clockwise manipulation.

My question is how much is too much ?

Will this effect picture quality one to another ?

Thanks
ITW

It's quite common for that lens (or indeed ANY lens, but the 100-400L seems to have more slack than most) to be able to rotate a little once mounted. If it was absolutely tight, any heat expansion on a hot day could make the lens impossible to mount or unmount, there has to be a little play in the system.

My 100-400L also rotates quite noticeably but it is nothing to worry about as you have a circular lens, projecyting a circular image into the camera. The image doesn't rotate with the lens, so the projected image onto your sensor is identical whatever degree the lens is rotated to. The only way a difference would occur is if the lens could be tilted slightly up/down or left/right, as that would mean it wasn't perfectly straight on to the sensor. But, rotation is fine so don't worry.

If I had to guess, I'd say my 100-400 L on my 5D2 rotates about a quarter of a millimetre. There must be some tolerance otherwise there's a risk of jambing.

It has absolutely zero effect on the picture quality.

You might also find this varies quite a bit based on lens construction and even different manufacturers. My Sigma 17-50 (metal mount) is quite snug in all respects but I've had a Canon 18-55 (plastic mount) which was loose in much the manner as you describe.

Borrow a 28-135. The slop in that lens gets horrendous, and it still works fine. I have a 100-400L and have never noticed movement.

My mistake. I thought this was about play in the lens, not play at the mount. Sorry.

If there was no play at all very few combos would mount just due to manufacturing tolerances.

If you look closely at the hole that the locking pin goes into, it is *slightly* oblong there; it's just moving within that space.

my 70-200 moved quite a bit on my 5d2. less so on my 5d3. I'm sure it's ok.

Hello, and thanks to all for the unanimous confirmation !

My gut told me all was well, especially after observing the quality of the pieces involved and the consistency of the shots I was getting, but I needed to hear it from those in the know and you guys came through in spades ! The reasons for the play that were mentioned above clearly make sense to me.

I'm on the road and unfamiliar with the area so today after posting here, I took my rig to a local Big Box store and asked if I could mount my lens on one of their bodies to compare. I was relieved to feel that the fit was even a tad more sloppy than mine and happier still to come back to all your comments.

Valuable resource here at POTN, I like the spirit of the place.

Thanks again !