Help with a 13" Cooke series II missing a screw

[Mattk]

Wondering if anyone can help enlighten me. I've not yet had the lens in hand and its missing a screw on the soft focus ring. I'm guessing this helps couple the SF mechanism. Aperature is free, glass is perfect. Probability of replacing/retapping the screw? Anyone have one of these apart? 205130205130

[Steven Tribe]

I think it may be the reverse!

I have seen a few Cooke lenses with extra locking screws which seizes the soft focus adjustment in a particular setting - probably sharp.
Most of these lenses started life as a Studio camera with “junior” staff employed. Perhaps the boss had seen too many examples of super softness.

I do have a dismantled Series II Cooke and will check (when I find it) whether the grub screw is an embelishment rather than a standard part of the central lens movement.

[Mattk]

Fantastic! Thank you Steven. I’ve just started back up after a long time away. Finally have a real darkroom with a real sink and I’m looking at picking up that lens to go with a few other soft focus lenses. Used a Darlot last night that’s been sitting for years waiting to be used.

[Mattk]

Ok, went and looked at the lens. Soft focus movement is free and easy. Looks to me that maybe the screw added friction to the SF rotational movement as I couldn't see any hole that lined up as I rotated it. Aperature is extremely stiff-I was able to get it to budge. Steve-do recall how difficult it was to dissaemble the lens. I am comfortable cleaning up the aperture movement if I can get it open. Now to decide if its worth it to me to buy it along with a studio camera I don't need.

[Ron (Netherlands)]

Is yours the 10,5 or 18 inch version? On the one below it seems the screw sticks out a bit (pic found on internet):

https://cdn.globalauctionplatform.com/db9b2a91-18bf-4d29-a234-a6a200a825f2/5bb09626-a9fa-496b-fcaf-dadf5ff80503/original.jpg

https://www.mwclassic.com/wp-content/uploads/2018/11/mwclassiccameras-20181116-110.jpg

[Mattk]

13.1” version. It appears that several lenses I’ve been able to track down images of have a small knob (pea sized) on a short post to act as a soft focus lever.

[Steven Tribe]

Found my dismantled 10.4” Series II - exactly where I left it!
It is a simple Locking screw which screws into a thread in the Inner barrel. When it is installed, the “sharp” is exactly opposite the arrow . Now the adjustment on this version is very low tech - just a screw thread which can be taken past the “sharp” indication. This means that the lost screw could be used to locate the correct sharp position - and not a complete turn always from it!

In my example, the fine screw has been sheared off at some time In the past.
My problem is a u/s Iris, which I will replace with Warehouse stops - sometime?

[Steven Tribe]

13.1” version. It appears that several lenses I’ve been able to track down images of have a small knob (pea sized) on a short post to act as a soft focus lever.

I think this is the earlier version.

[Mattk]

Just an update in case others stumble upon the same question. I purchased the lens and was able to free up the aperature nicely. The missing screw in question appears to engage (or run into) two posts on the lens barrel creating limits the rotational travel. In my case with a pin installed, the lens rotates nearly a full turn in the soft direction before running into the next stop. Hope this helps someone else!