Coating issue on rear cell?

[Daniel.E]

Yes I think it's coating too now, the seller told me it's on the outside of the rear cell.

[Kevin Crisp]

I didn't get an answer to whether it is on the surface. Coating issues, usually from faulty cleaning, generally don't have so much emphasis on the edges.

I'm not sure somebody starting out in LF really needs to get into recementing lenses right away....

[Daniel.E]

If the problem is not obviously right on the surface of the outermost glass of the rear element, it is likely separation which is an expensive problem to fix.

Sorry Kevin, I missed that one. Yes, the problem is right on the surface of the outermost glass of the rear element. That's what the seller told me.

It sounds tempting but I certainly wouldn't go into recementing lenses.

[Daniel.E]

Here's a video of what it looks like https://www.dropbox.com/s/qp2lx82fk0...61877.mp4?dl=0

[Kevin Crisp]

Interesting. If somebody slopped a little oil on the inside of the rear element, and then cleaned it off, you might get this effect. Some older coatings were very soft on vulnerable.

[Dan Fromm]

Why do you think the lens is coated? What is its serial number?

[Daniel.E]

The serial number is 3,xxx,xxx according to what I read after the 2,7xx,xxx the lenses appear to be factory coated.

[EdSawyer]

That's actually the inside of the rear cell, but indeed looks like coating issue as mentioned.