Anyone know what this is?

[xj0hnx]

These spots don't come off, anyone know what it is?

 

[dxqcanada]

Could be that the multicoating is wearing off the rear lens element.

 

[Gavjenks]

Looks like the coating is chipped off to me. Whatever it is, it's pretty severe and demands a large discount.
However, doesn't mean the lens is useless. I have a lens with big gouges in it almost as big as that and it works fine. Little lower contrast than it might be otherwise, that's about it. ...Or it could show up in every image and be worthless. Just gotta test it.

 

[vimwiz]

Coating wearing off. (probably a bad cleaning, or fungus removal at some point)

I have a similar much but much smaller mark on one of my old canon FD lenses. Doesnt seem to afect picture quality for me, but mine is only about 3x1mm. If its a bad cleaning though, and someone i.e. uses abrasives, it could be ruined.

 

[timor]

Yup, they are not spots, they are holes in coating layer.

 

[xj0hnx]

I was thinking that was it, but wanted second, third fourth opinions. It doesn't seem to effect the photos directly though, but this lens does have some odd focus issues I am learning to deal with. It is finicky about focusing to infinity. Anyway, gotta go burn through some more film.

 

[timor]

I was thinking that was it, but wanted second, third fourth opinions. It doesn't seem to effect the photos directly though, but this lens does have some odd focus issues I am learning to deal with. It is finicky about focusing to infinity. Anyway, gotta go burn through some more film.

As long as you shoot b&w it will not have much apparent effect. It is the last coating after all. But it may be visible on colour film as those coatings are balancing the spectrum of light coming in.