Damaged lens artefacts

[Berengar]

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Hi guys,

I'm happy to be here and since it is my first post please forgive me if I'm posting a request that might have been already discussed.
Anyway I couldn't find anything super close that's why I'd like to hear your opinion on my issue.

I own some Leica R lenses - 28mm f2.8, 35mm f2.0, 50mm f1.4 & 90mm f2.0 - and with the 35 one I receive a specific artefact in a specific lighting condition.

The lens in general seems to be in a very good condition.
From the outside there's no scratches on front and rear elements.
Inside the glass there's few dust particles and 1 or 2 small fibre elements.

Could you please examine the attached images and tell me your opinion on what might cause that tiny line in many bokeh circles repeating?

Thanks a lot in advance!

Cheers

 

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[davidmknoble]

It seems like they are in different places.  Middle, then left, etc.  I am not sure, but I would suggest shooting on a tripod so the ‘bokeh’ balls are all in exactly the same place, then rotate and shoot again.  It is possible it is the lens, but may also have to do with the light source?

Also, what camera are you using, digital or film?  If digital, could be something on the senor?

Also, try shining a flashlight along the front of the lens and look through the back.  Not directly, but at an angle to look for cleaning marks harder to see.  

They seem fairly clear wide open which is a little odd as normally these things are not as noticeable wide open, but much more so stopped down.

Just some thoughts…

[hepcat]

That's pretty interesting.  As David suggests above, use a strong LED flashlight and examine the edges of the elements closely through the lens.  All of the bubbles that have lines are near the edge of the image, and appear to have the curved line in the upper right hand corner and appear concave.  That means that whatever is causing them would be in the upper right of the lens as mounted, looking through the shutter (if I'm thinking about this right.)   It looks like perhaps something at the very edge of one of the elements is reflecting or refracting something internally? 

Do you have a filter mounted?  What body, shutter speed and ISO are you using?  Does the line appear when you're shooting at a white, constant surface? 

[Berengar]

Thank you for your comments and help guys. I appreciate.

I did the same test (same camera settings and light setup) with my other Leica R lenses + with another sample of a Summicron 35 f2 and there wasn't anything similar there ...well, the second sample has a tiny scratch in the rear element and you would never see it until you make such a test I guess ...please take a look on the next batch of images from the other lenses though.

There's no filters attached btw

I am aware that some dust particles might also contribute to some artifacts in such situations but not as geometrical as you can see in my 1st post ..

P.S. the image without the label is the 35 f2 with the tiny scratch in rear element

 

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[Berengar]

Hi cbass,

thank you for your opinion.

Here the case is that someone is trying to sell this lens to me describing the item as 'flawless' / 'top condition' ... you name it ...
And that's when I say your '95%' is not enough.
Besides I think a hair or other contamination wouldn't create such a geometrical imperfection.

[earleygallery]

If you are not happy return the lens and get a refund.

IMHO it is probably one of the 'fibres' you mentioned inside the lens. A scratch wouldn't be visible.

The other option is to have the lens CLA'd.