How to tell if I have oil on blades?

[DerekF]

I finally received my used 35 Summicron off the 'bay last week and have been checking it out. The first thing I noticed is that there is something "shiny" on the aperture blades, but I can't tell if it's oil or maybe just brassing of the aperture blades from years of use (does that happen to aperture blades?). I notice this shiny stuff/reflection in the middle of the lens on all of the blades with the aperture set to its smallest (f16) and a few smaller lines of it toward the outer edges of the blades with the aperture set to f8. The ones on the outer parts of the blades seem to line up with each other when I set the aperture wide open to f2.

My friend has my digital camera so I can't provide pics right now, but does this sound like oil? Or is it something else?

Any tips appreciated!

 

[FrankS]

It's either oil or wear. Does it look wet?

 

[FrankS]

If it's oil, it would make the un-worn black blades look blacker where the oil is.

 

[peter_n]

If you're seeing it on the outer edge of the blades that might suggest wear on blades that are not completely flat.

 

[ray_g]

Sounds like wear from your description. As Frank said, oil would look wet and dark, and not like the "brassing" you describe.

 

[DerekF]

Sherry Krauter or DAG for CLA?

Sherry Krauter or DAG for CLA?

Well I think I've managed to strike a deal with the person who sold me the lens. They've agreed to foot the bill for a CLA of the lens in question, so I've decided on either Sherry Krauter or DAG, since they seem to get the most recommendations. (Does Kindermann still do CLAs of Leica lenses? I emailed them for a quote but have yet to hear anything back from them yet..)

DAG's estimate came in a bit higher than Sherry's and both quoted a turnaround time of about three weeks. Is one preferable over the other? Any experiences to share?

 

[brightsky]

DAG provides a 6 month warranty on a lens CLA, at least he did for my old Summilux sent last fall.

CM