Strange 'defect' with W-Komura 28mm f3.5 Sankyo Kohki Lens

[frostfire90]

Hello Everyone,

This is perhaps one of my few times posting on the forum. I sincerely thank the community for all the invaluable information i've gained looking through this forum

This lens which i have has a tiny perfect circle within the lens element itself. It is certainly not haze nor fungus, and i highly doubt that it is separation. I couldnt find any information on the web about it, the closest being 'basalm fault' which isn't the case either. Does anyone know what this is and if it should be of a concern? The picture is attached below, and thanks for your inputs

Cheers,
Yuhan

[raytoei@gmail.com]

is it a bubble ?

[Speedfreak]

It may be separation, it may also be a glass failure. But most importantly: Does it show on the pictures? If no, I wouldnt worry.

[frostfire90]

Nope i dont think it's a bubble as i've seen how bubbles look like. They're usually much smaller unlike this one. No problems from what ive noticed from the pictures, but just concerned about the resale value =/

[frostfire90]

Does anyone have a similar experience with such a lens?

[FrankS]

Could it be a droplet of moisture? Try jarring the lens in your hand (use a reasonable amount of force) to see if it moves.

[ottluuk]

Looks like a bubble to me. If it indeed is one, it's probably harmless as far as image quality is concerned.

[frostfire90]

Thanks for your responses. Nope it is not a droplet of water, and upon closer inspection i realised that there is actually a smaller circle within that circle! Strange, and it doesn't look like a bubble to me cause it's planar instead of three dimensional, if i even make sense =/ im starting to believe that this is part of the lens design itself!