Question About 24-70 F2.8 Rear Mount and Screws

01/29/2012 09:39:25 PM · #1

Okay, so I need some quick help tonight for those of you who have the Canon EF 24-70 F2.8. So the one I said I found I am actually doing a lens swap/trial with the guys before we both decide. I have used the lens for the last 48 hours and it works great. The only thing I have noticed is that some screws seem strange on the rear mount. So if someone could upload pictures of the rear mount as shown in this picture that would help. What I have noticed is that the set screw appears to be missing and there's a screw right under the connector that isn't flush. I have had a heck of a time finding views online that clearly show which screws are supposed to be in this particular area. We're meeting back up tomorrow. Thanks everyone.

The set screw goes in that spot underneath the ledge and the non-flush screw is right at the left edge below the connector.

Message edited by author 2012-01-29 21:51:13.

Samsung Galaxy S24, S24+, S24 Ultra

01/29/2012 09:46:39 PM · #2

When viewed from the same perspective, mine looks slightly different. All the same screws are present, in the same locations, but the height of the two screws in the slot is different. On yours, it appears that the left screw (directly under the end of the flange segment) is below-flush. On mine, it is above-flush. On yours, the right-hand screw in the slot (just left of directly under the left-most contact) seems to be above-flush, and mine is below.
Is that the difference you are referring to?

ETA: I just looked at 4 other EF lenses of mine and they all look the same as my 24-70.

Message edited by author 2012-01-29 21:49:11.

Bear_Music

Sony 24-70mm F4 Vario-Tessar T* FE OSS

01/29/2012 09:48:22 PM · #3

There's NO screw under the flange, Fritz... There's supposed to be a protruding set-screw there. It's the same on all EF mounts.

Message edited by author 2012-01-29 21:48:32.

01/29/2012 09:50:41 PM · #4

Originally posted by Bear_Music:

There's NO screw under the flange, Fritz... There's supposed to be a protruding set-screw there. It's the same on all EF mounts.

Yep. And it is, on at least four of mine. There is a second setscrew, to the right of the protruding one, and that one is below flush. On his example,, though, it looks as if the right one is protruding, and the left is below-flush. WTF?

01/29/2012 09:53:33 PM · #5

Updated the picture to show the arrows to make sure we're talking about the same thing...

Samsung Galaxy S24, S24+, S24 Ultra

01/29/2012 10:05:07 PM · #6

The lens is sharp as a tack though, so I'm wondering what you guys would do...

Bear_Music

Sony 24-70mm F4 Vario-Tessar T* FE OSS

01/29/2012 10:08:25 PM · #7

Originally posted by goinskiing:

Updated the picture to show the arrows to make sure we're talking about the same thing...

Right, that's what I was saying: the leftmost arrow points to an empty screw hole where there should be a stud type of screw, a screwpost, that protrudes and is a limiter of some sort. All my lenses have it. The other arrow, the rightmost arrow, points to a flathead screw that should be flush and is not.

Have you tried tightening the one? that might be all it needs. Where your little post screw has gone I do not know, but iot ought to be easy enough to find and install one, eh?

R.

01/29/2012 10:10:42 PM · #8

Originally posted by Bear_Music:

Originally posted by goinskiing:
Updated the picture to show the arrows to make sure we're talking about the same thing...

Right, that's what I was saying: the leftmost arrow points to an empty screw hole where there should be a stud type of screw, a screwpost, that protrudes and is a limiter of some sort. All my lenses have it. The other arrow, the rightmost arrow, points to a flathead screw that should be flush and is not.

Have you tried tightening the one? that might be all it needs. Where your little post screw has gone I do not know, but iot ought to be easy enough to find and install one, eh?

R.

That's what I was thinking too Bear, I just wasn't sure if that would be bad form to try and tighten it when technically I'm still borrowing it. A try before you buy sort of thing, he has my 17-40. I'm sending an email with a picture to him asking if he knows anything about it.

01/29/2012 10:12:47 PM · #9

Here's a shot of mine...

Samsung Galaxy S24, S24+, S24 Ultra

01/29/2012 10:17:19 PM · #10

Originally posted by kirbic:

Here's a shot of mine...

Interesting, so that screw on the right can go quite a ways more in then? I wonder how hard it would be to find the left post set screw? I'm still waiting back from the guy as we're meeting back up tomorrow to see what he knows about it. I don't think it's a deal-breaker as the lens performed very well, ~1000 shots over the weekend and was fantastic! Perhaps a price negotiation point?

Bear_Music

Sony 24-70mm F4 Vario-Tessar T* FE OSS

01/29/2012 10:27:08 PM · #11

Originally posted by goinskiing:

I wonder how hard it would be to find the left post set screw? I'm still waiting back from the guy as we're meeting back up tomorrow to see what he knows about it. I don't think it's a deal-breaker as the lens performed very well, ~1000 shots over the weekend and was fantastic! Perhaps a price negotiation point?

If he doesn't think it's worth negotiating, if he thinks it's a negligible matter, then tell him "Fine! We'll take the post off my 17-40 and swap it onto the 24-70 and we're good to go!"

R.

snaffles

Nikon D7100

Nikon AF-S DX NIKKOR 18-200mm f/3.5-5.6G ED VR II

01/29/2012 10:34:39 PM · #12

I don't want to say what images went through my head when I first saw the title of this thread...;-)

01/29/2012 10:38:18 PM · #13

Originally posted by snaffles:

I don't want to say what images went through my head when I first saw the title of this thread...;-)

8-o

01/29/2012 10:47:44 PM · #14

Originally posted by snaffles:

I don't want to say what images went through my head when I first saw the title of this thread...;-)

Oh my, bad wording.

01/29/2012 11:39:25 PM · #15

So I talked to the guy (super nice), and he said he had forgotten about that and was sorry he forgot to tell me and said he'd either fix it or bump the price down (on an already good deal IMO). Anyways, it performed like a champ over the weekend and produced some stellar shots. It's looking good that it'll be in my arsenal permanently. I also asked him about the screw that wasn't flush and he said I was fine to screw it back in. I did so and there was no problem at all. Does anyone know where to find a set screw/post? I looked on ebay and amazon.com to no avail. Thanks for everyone's input!

Giles

Canon EOS-5D Mark III