Calling all YS lens mount users

[xkaes]

I've just received my second YS lens. They are both great lenses, and both made by Sigma -- although one is labeled SPIRATONE. Spiratone sold a lot of Sigma lenses, FYI.

My first is a Sigma 135mm f1.8. The new one, that I just received is a Spiratone 300mm f4.0.

While needing to make a minor adjustment to the YS mount on the 300mm -- without an instruction sheet -- I opted to go on-line and found this page from BUTKUS

https://www.butkus.org/chinon/y-s_mount/ys.htm

It (I don't know if Butkus wrote it, but it is on his website) clearly states:

"All YS adapter mounts (and lenses) have the identical specifications as T Mount lenses and adapters so that T adapters may be used on YS lenses for those cameras for which no YS adapters may be available. Naturally, with T adapter the operation of YS lenses would be non-automatic."

Neither of my two YS lenses have a T-mount underneath when the YS mount is removed. They have simple, unthreaded, slightly-angled, short barrels for the three side-screws to grip.

Have any of you YS users ever seen a YS lens that has a threaded barrel underneath the YS mount? I'd send a picture, but YS mounts can be a nuisance to undo.

 

[AgX]

It (I don't know if Butkus wrote it, but it is on his website) clearly states:

"All YS adapter mounts (and lenses) have the identical specifications as T Mount lenses and adapters so that T adapters may be used on YS lenses for those cameras for which no YS adapters may be available. Naturally, with T adapter the operation of YS lenses would be non-automatic."

It is indeed by Sigma, second paragraph on page one of the YS-lenses manual.

Furthermore the manual explicetely says to screw on the adapter.


The YS-adapter you got is split and turnable in itself, after releasing those locking screwes.

This is unlocking is described in the manual too. Thus in all likelyness you did not take off the adapter but disassembled it.

 

[xkaes]

Thanks for the response, but it's of little help. As I stated, I don't have a manual, and the BUTKUS page is not a manual, only instructions.

When I follow the instructions -- removing the three screws on the side of the mount, marked "YS -- Japan" -- the mount comes off, but there are no threads underneath, on the rear of the lens, for a T-mount.

The removed YS mount is the same length/depth as a T-mount, but there is no way to attach a T-mount.

Does anyone actually have a YS manual?

 

[xkaes]

It's OK if a T-mount cannot be substituted on my lenses, but having them with a T-mount would be nice in some situations.

 

[MattKing]

Threads combined in the Camera repair and modification sub-forum, and duplicate information deleted.

 

[AgX]

Thanks for the response, but it's of little help. As I stated, I don't have a manual, and the BUTKUS page is not a manual, only instructions.

I got the manual, and refering to that manual and getting as reply to be of little help is weird.

 

[AgX]

The removed YS mount is the same length/depth as a T-mount, but there is no way to attach a T-mount.

The length being identical does not contradict what I cited from the manual.


However at the two YS-mount lenses I tried I was not yet able to screw off that adapter, respectively that stub of the adapter.
Seemingly at YS-lenses that T-thread coupling for unknown reasons seems to freeze.


I guess that in some mount cases it may work then to just exchange that rear part of the adapter.

 

[xkaes]

The length being identical does not contradict what I cited from the manual.

I guess that in some mount cases it may work then to just exchange that rear part of the adapter.

You suggested that I didn't completely remove the YS mount. I contend that I did. The part that I did remove has the exact same depth as a T-mount. If there was something else to remove, and if I could somehow screw-on a T-mount, the lens would no longer be focused according to the distance scale. The distance to the film would be shortened.

The section in front of the YS mount has the aperture ring for the particular lens and is not part of the YS mount. For example, the f-stop scale on my 300mm runs from f4 to f22, but the scale on the YS mount itself, runs from f1.8 to f32.

I guess I'll have to take some pictures.

Does anyone happen to have a genuine manual that they can upload. BUTKUS does not have one.

 

[AgX]

The part that I did remove has the exact same depth as a T-mount. If there was something else to remove, and if I could somehow screw-on a T-mount, the lens would no longer be focused according to the distance scale. The distance to the film would be shortened.

{Moderator's edit of unnecessary argument}

Why then not substitute this by a loupe and a caliper?

 

[AgX]

{Moderator's edit of unnecessary argument}

The YS-adapter need not be longer than the T-mount when the YS-adapter is just screwed onto the T-thread.
Why not have a closer look by means of a loupe and a caliper? This would show a slit between the lens barrel and the inner part of the YS-adapter, just as at a retaining ring or cap nut. Using the caliper would show that the circular slit at that inner part at its facial side got a diameter of about 41.1mm, indicating that T-mount thread.

 

[AgX]

I guess that in some mount cases it may work then to just exchange that rear part of the adapter.

Actually no reason comes to my mind that the T-threaded inner part is not a generic one at all YS-adapters. Thus in case one is not able to remove this without tools, one could just exchange the outer parts of the adapters.


To remove it nonetheless one can drill two holes into its facial plane max. 3mm deep and try to screw it off by means of an angled pinned wrench.

However...
Chances are that a former owner has cemented the adapter onto the lens barrel. So look out for residues of cement at the circular slit in the facial plate I hintead at above. Of course, lacking of such residue does not make one wiser...

 

[MattKing]

I've done more editing in this thread than normal, in order to delete personalized argument and retain some of what that might actually be useful.

 

[xkaes]

Hopefully I'm the only one that has ever had this "problem". I can use both of my YS lenses as is -- they work fine -- so it's not really a problem. And most people who are users of YS lenses won't have explored this question.

I was just exploring the BUTKUS page that indicates that there is a hidden T-mount thread inside YS lenses. Seems possible, but they don't provide any evidence. I can't find it on my two lenses -- although I can take the YS mounts off of each.

I'll see if I can take a couple of pictures tomorrow.

 

[AgX]

It is a hopeless case, when respective advice from a member which got the manual and the lenses, with and without an adapter mounted, is ignored.

 

[xkaes]

Here are two photos of one of my YS lenses -- they are almost exactly the same. The first shows the lens with the YS mount ON, the second with the YS mount OFF.

You can see in the second photo that there are no threads at all -- so no way to attach a T-mount as has been suggested on the BUTKUS website.

To me, it would be very odd for Sigma to develop an alternative to the T-system that would somehow allow a T-mount to be used. The width of the unthreaded ring on the YS lens that attaches to the YS mount (with three screws) is 52mm -- MUCH wider than the 42mm T-mount thread.

This is OK with me, because the YS mounts I have work fine, but having a T-mount as well would add some versatility for me.

Until I see otherwise, maybe this just proves, once again, that you can't believe everything you read on the Internet.

 

[xkaes]

It is a hopeless case, when respective advice from a member which got the manual and the lenses, with and without an adapter mounted, is ignored.

Why won't you actually share the actual manual if you actually have it?

 

[reddesert]

The Butkus page is a transcription and HTML-ization of the text from an instruction book. He does that sometimes, perhaps to make it easier to read.

I think the thing in your picture is the inner part of a mount, like a two-part T mount. That is, the mount has an inner threaded collar, and then an outer part with the camera mount flanges and setscrews that pin the outer to the inner. The inner part should screw off the lens if you can get a grip on it (or if you reassemble it and use the outer as a grip). This inner-outer arrangement and the setscrews allow the user to adjust the angle of the lens relative to the body if it doesn't wind up exactly aligned once mounted, as with many T-mount accessories. I don't have a YS mount lens to experiment on, though.

 

[xkaes]

Thanks for the thoughts. Apparently the YS mount is not as common as I would have guessed.

If you look at the second picture, there is nothing left on the lens to remove. The only thing there is, is the aperture ring. That is not adjustable, of course (the YS mount is what is adjustable, as with a T2-adpater) and removing the f-stop dial would only screw-up the lens. In addition, if there is a T-mount under there, screwing in a T-mount would eliminate the aperture ring.

Here is a picture of a new mount -- exactly like the ones I have -- from EBAY today. This is the entire YS mount. There is no thread of any diameter on the front. I've removed this same mount from my two lenses, and there is no thread underneath on the lens -- just a 52mm ring that the three side-screws press up against.

The first picture on the BUTKUS webspage (showing a YS Nikon mount being attached) shows the mount BEHIND the aperture ring. The f-stop dial is part of the lens -- just like in my second photo (above) -- and the YS mount is attached behind the f-stop ring -- as in my first photo.

As to the BUTKUS web page, if it is a transcription, it's a pretty poor one because there are contradictions -- and what looks like some "ad lib".

So I'm as confused as ever. The two YS mounts and lenses that I have all work fine, so I'll just leave it at that.

Maybe I can get this EBAY seller to send me a copy of the instruction sheet -- AND SEND IT TO BUTKUS!!!

 

[MattKing]

If you look at the second picture, there is nothing left on the lens to remove.

I'm willing to bet that the thin ring I've marked in red is screwed on to a T thread that I've marked in blue.

 

[AgX]

I'm willing to bet that the thin ring I've marked in red is screwed on to a T thread that I've marked in blue.

I was saying so from the start...


One has to mount the outer (dedicated) part again, set the set-screws firmly and twist off the complete adapter. If this does not work, screw out the set-screws again, take off the outer part of the adapter and proceed with the alternatives I gave above.

 

[xkaes]

I'm willing to bet that the thin ring I've marked in red is screwed on to a T thread that I've marked in blue.

You nailed it.

I tried that approach on one, but it wouldn't budge. But on the other one, only a little encouragement was needed. I managed to force the other one off without any damage.

Now I can use both of these lenses on other cameras with T2-mounts. I'll keep my eyes open for other YS mounts -- there are lots of them on EBAY but the prices are all over the place, from $10 to $100.

Thanks for helping me solve this problem!!! I hope it helps out others as well.

 

[AgX]

I tried that approach on one, but it wouldn't budge. But on the other one, only a little encouragement was needed. I managed to force the other one off without any damage.

Now I can use both of these lenses on other cameras with T2-mounts.

How would that work when at one of the two lenses the generic part of the adapter is frozen?

 

[xkaes]

On one I needed to use WIDE pliers. Fortunately it wasn't glued in place. The other was only normal tight.

I'll be on the look-out for a YS-M42 mount.

 

[xkaes]

Now I've got a new problem -- related to the same lens.

I've removed the YS mount and installed a T2-mount instead. The problem is that the T-mount on a YS lens does NOT press the aperture button on the YS lens, so the YS lens stays at full aperture all the time.

I need a way to keep the aperture button pressed in all the time. You can see the aperture button/tab in the second photo I posted (above). It's the silver button on the far side of the lens -- inside the T-mount ring.

I could glue it in place, but I don't want to do that, since it's permanent.

I've tried small pieces of tape, but they just don't stay in place very long.

All of the T-mount lenses that I have either don't have a diaphragm (mirror lenses) or are preset lenses (ex. Tokina 800mm f8), so I have no experience with T-mounts on auto-diaphragm lenses.

Anyone have any suggestions?