newb help: mounting a lens

[kevinc11]

I am a 4x5 newb. I'm hoping someone can help me figure out how to mount my lens.
I recently purchased a Schneider Xenar 150mm f4.5 Lens Compur Shutter from Ebay. Separately, I bought a Copal 1 lens board.

If you see the attached picture (from the ebay listing) there is a large ring -- not the retaining ring that can screw off -- surrounding the back of the lens. Do I remove this ring to attach the lens? Right now the lens does not fit on the board. I've researched and I have the correct Copal size and I've measured to make sure I didn't receive an incorrect one by mistake.

If I look at other examples of this lens -- https://www.camleyphotographic.com/shop/schneider-xenar-f4-5-150mm-lens-w-compur-shutter-condition-5e-6181/ -- that large ring is not on the back of the lens.

Is there anyone that can possibly offer advice on how to mount this lens?

Thank you in advance for your time and help.

188886

[Jac@stafford.net]

Does your ring screw onto the lens? If it does, then technically it is a flange which is to be screwed onto the front of the board. If it does not screw onto your lens you have received inappropriate mounting. IOW, screwed.

[kevinc11]

Thanks for the prompt reply. The ring screws on the back of the lens, on the larger ring I mentioned. Is that what you mean?
Attaching a photo here. 188890

[Bob Salomon]

Unscrew that threaded ring on the back. Then you will need a retaining ring.
Throw that piece that you unscrew away.
It looks like somebody salvaged this lens from a piece of equipment.

Otherwise return it and buy from someone else.

[kevinc11]

Hi Bob, I'm unable to remove the large ring. It can't be screwed off.

Looks like returning is my only option.

[Bob Salomon]

Hi Bob, I'm unable to remove the large ring. It can't be screwed off.

Looks like returning is my only option.

And buy a better lens, like a plasmat in a 0 shutter if it is a 150mm.

[Jac@stafford.net]

Hi Bob, I'm unable to remove the large ring. It can't be screwed off.

Looks like returning is my only option.

I do not understand. It must screw off or up. Is the ring in your photo stuck in place?
If it cannot be screwed off look for a tiny screw on the ring and if it exists, then back it off.

[kevinc11]

The retaining ring can be taken off. The larger ring cannot.
If you look at this picture the larger ring is not attached to the back of this lens
https://www.camleyphotographic.com/wp-content/uploads/2017/07/Schneider-Xenar-f4.5-150mm-Lens-w-Compur-Shutter.-Condition-5E-6181-1.jpg

[Leigh]

The ring screws on the back of the lens, on the larger ring I mentioned.
That is not a standard mounting arrangement.

The regular retaining ring is shown on the last photograph you linked. Those rings are undercut on the side facing the shutter. That reduced diameter fits in the lensboard hole. The larger portion bears against the back of the lensboard.

- Leigh

[AJ Edmondson]

Maybe my eyesight is worse than I thought but it looks (to me) as if the rear lens group is from a different lens. Have you checked to see if the lens casts an image at about six inches ( just open the shutter, and hold it about six inches from a white wall or piece of paper while pointing it toward a window. I may be completely wrong (wouldn't be the first time).
Joel