ED 100-400 f5.0-6.3 loose on mount?

sunnydayz wrote:

For your interest please compare the locking detent on the 100-400mm to other lenses you may have for MFT. I made the comparison on my lenses and this is what I found.

Refer to the attached pictures.

Measured with digital caliper: 2.1mm width

Measured with digital caliper: 2.04mm width

I also measured the diameter of the rotation locking pin on 2 camera bodies and MC-14 and MC-20. The pin diameter was 1.95mm.

Now it is a matter of simple math.

For 100-400mm: 2.1mm - 1.95mm = 0.15mm clearance

For other lenses: 2.04mm - 1.95mm = 0.09mm clearance

We can see that there is a difference in the clearance. With the 100-400mm, there is a total rotation play of 0.15mm, whereas other lenses the total rotation play is 0.09mm.

These are calculations based on my lenses. You will have to measure your own lenses to compare. Your 100-400mm locking detent width may be larger which would result in more rotation play.

You may also ask why on a 'good' lens it feels rock solid, no rotational play even though there is a designed in mechanical clearance. Well there is rotation play as well, but you might have to force the rotation to feel it. One other thing to consider is the gap of the 3 lens lugs to the base of the lens mount. You would have to measure both the 100-400mm and other lenses to see if the gap is slightly bigger in the 100-400mm. If the gap is bigger, then the lugs are not holding the lens as tight against the camera body lens mount which will add to the felt slippage that occurs. All these little mechanical tolerances add up.

Other users have noted that the lens is rock solid or just slightly slipping on their camera bodies (previous discussion), so this does indicate slight differences in either the lens locking detent width, lug gap or even the camera body lens mount.

My situation is that I have very minor rotational play on my 100-400mm but it does not bother me. I didn't even notice it until this was brought up as a problem and I tested my lens for rotational play.

Hope this is helpful to understand what may be causing your problem.

Sunny,

Notice that the feature is designed differently.

The 2.1mm on the larger lens is very different than the 2.04mm slot on the smaller lens.

The tighter fitting lens has a slot with 2 flat sides. As the slot widens in terms of mfg tolerance, the rads get bigger and flats get smaller.

On the 100 to 400, there seems to be a hole with another feature below it. It seems to be a thru slot of sorts.  The hole is actually larger than the length of the slot on the smaller lens.

Interesting.

Best Regards,

Bernard

Yes mine moves slightly on my EM1 markiii. But I am not concerned as the seal seems fine.

It is supposed to be weather resistant and I cant see why that wouldn't still be the case.

Also it is under 18 months guarantee.

Alex_Ochkasov wrote:

OuP wrote:

Anyone have this issue? Got the lens a couple of days back and noted the lens is loose on the mount - rotates about 0.5mm (maybe more) but certainly noticeable. Tried it on OMD EM1 Mk11 and OMD EM1 M1 with same results. Checked other lenses and these don't rotate. Is this a faulty lens which should be sent back for a replacement?
Your advice appreciated.
OuP

I have a same problem on my E-M1-1 and E-P5

I make a new topic because i found your comment only now.

Topic mount movement with 100-400

I posted some 2 videos: have you same mount movements?

sunnydayz wrote:

For your interest please compare the locking detent on the 100-400mm to other lenses you may have for MFT. I made the comparison on my lenses and this is what I found.

Refer to the attached pictures.

Measured with digital caliper: 2.1mm width

Measured with digital caliper: 2.04mm width

I've been meaning to ask (purely out of curiosity) - if you or any other forum members happen to have any Sigma lenses with an m43 mount (I don't) - do they have the same design of locking pin recess as the Olympus 100-400mm? Thanks.

Helen wrote;

I've been meaning to ask (purely out of curiosity) - if you or any other forum members happen to have any Sigma lenses with an m43 mount (I don't) - do they have the same design of locking pin recess as the Olympus 100-400mm? Thanks.

Helen,

That is a really good question.

Best Regards,.

Bernard

sunnydayz wrote:

Helen wrote:

I've been meaning to ask (purely out of curiosity) - if you or any other forum members happen to have any Sigma lenses with an m43 mount (I don't) - do they have the same design of locking pin recess as the Olympus 100-400mm? Thanks.

I don't have any Sigma m43 lenses, but found on ebay some lenses for comparison.

Full disclosure: These images belong to the respective owners of the lenses put up for sale on ebay. These images are posted here only for educational purposes.

Sigma 30mm f2.8 mft mount

Sigma 19mm f2.8 mft mount

Sigma 100-400mm Sony mount

Sigma 100-400mm Canon mount

The Sigma lenses mft or other camera mount shows a milled detent. Notice the Sigma 100-400mm for Sony and Canon mounts do not have the locking detent insert found on the Oly 100-400mm.

As a side note, out of curiosity I've checked rotation play on a couple of my film cameras and there is a little play as well. All lenses will have a small amount of rotation play as there must be some mechanical tolerance designed in. I'm sure you've read other posts here that someone had some other lens that was too tight and they could not even fully mount the lens on camera.

Anyway, on a case by case basis, I guess it boils down to whether the lens someone received is way out of tolerance or they just don't like any looseness at all. The only remedy then is to contact Olympus or the retailer and see if an exchange or return for full refund is possible.

Thanks for that reply and finding the pics. I don't have the Olympus 100-400mm myself, but was curious to know whether it was a typical Sigma design feature, since many have suggested that the lens appears to have some Sigma lineage. However, the smaller lenses have lock pin recesses more like a typical Olympus lens.  Hopefully, for those who have some rotational play in the mounting of their 100-400mm lenses, it doesn't cause any observable issues - for example, if the play was too much, I'd expect an electronic disconnection which would be very obvious (similar to the effect when one fully presses the lens release button accidentally on an Olympus body - no live view but instead a black screen with no aperture readout, just a pair of dashes, but all the rest of the graphics still present.

Bernard de Clairvaux wrote:

Helen wrote;

I've been meaning to ask (purely out of curiosity) - if you or any other forum members happen to have any Sigma lenses with an m43 mount (I don't) - do they have the same design of locking pin recess as the Olympus 100-400mm? Thanks.

Helen,

That is a really good question.

Best Regards,.

Bernard

Thanks (takes a bow). Looks like my suspicion about the locking pin recess had not led anywhere though...

sunnydayz wrote:

Helen wrote:

I've been meaning to ask (purely out of curiosity) - if you or any other forum members happen to have any Sigma lenses with an m43 mount (I don't) - do they have the same design of locking pin recess as the Olympus 100-400mm? Thanks.

I don't have any Sigma m43 lenses, but found on ebay some lenses for comparison.

Full disclosure: These images belong to the respective owners of the lenses put up for sale on ebay. These images are posted here only for educational purposes.

Sigma 30mm f2.8 mft mount

Sigma 19mm f2.8 mft mount

Sigma 100-400mm Sony mount

Sigma 100-400mm Canon mount

The Sigma lenses mft or other camera mount shows a milled detent. Notice the Sigma 100-400mm for Sony and Canon mounts do not have the locking detent insert found on the Oly 100-400mm.

As a side note, out of curiosity I've checked rotation play on a couple of my film cameras and there is a little play as well. All lenses will have a small amount of rotation play as there must be some mechanical tolerance designed in. I'm sure you've read other posts here that someone had some other lens that was too tight and they could not even fully mount the lens on camera.

Anyway, on a case by case basis, I guess it boils down to whether the lens someone received is way out of tolerance or they just don't like any looseness at all. The only remedy then is to contact Olympus or the retailer and see if an exchange or return for full refund is possible.

my 100-400 zuiko

My 12-40 pro

My 45 mm 2.8 sigma for Sony FE

I checked some size for pin and hole.

Em1mkii and penF and 12-40 are less of 2mm

Sigma and 100-400 are 2mm and this make the mount movement.

I hate little this movement because you can't buy an expensive lens and have this problems.

stevevp wrote:

Pollos wrote:

I checked some size for pin and hole.

Em1mkii and penF and 12-40 are less of 2mm

Sigma and 100-400 are 2mm and this make the mount movement.

I hate little this movement because you can't buy an expensive lens and have this problems.

As a matter of interest, what "problems" is a fraction of a millimetre of movement causing you? Have you spoken to Olympus about it?

I think will call them next week and I will ask if another 100-400's copy can be better.

I have been using the 100-400mm for the last week. While I don't think the rotational play is affecting image quality, it is a little irritating. One would think that there wouldn't be excessive tolerance in the locking slot in what is otherwise a well made, solid lens. I wrote to Olympus about this but have not heard back as yet.

Thanks to those who researched, measured and photographed the locking slot. It confirmed the problem.

OuP

Here is my question to Olympus:

"The lens rotates about 0.5mm when locked in on the camera mount. This is unlike any other Olympus lens that I use.. This problem has also been discussed in the Digital Photography Review M4/3 user forum. Please advise if this is an issue applicable to all 100-400mm lenses or is mine a "lemon" which should be returned?"

This is the Olympus reply:

"Thank you for contacting Olympus Technical Support.
Here is the official answer.
This is not a design mistake nor manufacturing mistake.
In order to achieve the smooth attachment and detachment of a lens, the size of a hole to fix the lens, which can be seen on the back of the lens, is designed slightly larger than a hole on a camera mount. And the hole size of the 100-400 mm lens is also within our standard. Because of this, when rotating a zoom ring and a focus ring, the lens might move a bit.
This does not affect the image quality or dust-/splash-proof performance. And users can use this lens without any concerns."

Olympus sees the "bit" of rotational movement as acceptable. Odd that their other lenses don't have the same amount of play.

I guess I will learn to live with it - it is a nice lens.