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Hi Everybody,

whilst cleaning my lenses yesterday i noticed that my Tamron 70-300 has two little bubbles in the glass
these bubbles are the size of two pinheads and are a few mms under the surface of the lens
noticed my Nikon lenses dont have such bubbles
anyone know what these bubbles are?
are they normal?
can they have any detrimental effects?

thanks

John

It is normal for bubbles to be in glass - how many pics have you shot with this lens and do you see any problems with the pics?

If the pics are OK - don’t worry

Interestingly, lens can be either plastic or glass - plastic is a solid and glass is a liquid (albeit supercooled liquid)

Hi John,

Sorry I can not help you with the problem to your lens...but, this is very much tongue in check, you haven't been to Bondi Beach taking picture of topless girls/ladies.


Cheers,

thanks Chris

yeah have taken 100s of pics with the lens and no probs
but was curious as to why bubbles

and Fozzie

shhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh if my wife finds out what those bubbles really are! LOL

Not unusual for high quality lenses to have a small bubble. They have no effect on image quality. Different story for very large bubbles though.

All optical glass can have some bubbles in it - when making high quality lenses the trick is to make them out of the bits without bubbles. These days though, most lenses (esp. those at the less expensive end of the market) start out as moulded blanks, to minimise the time for grinding and polishing.

The only effect of a small bubble would be a very slight increase in veiling glare (seen as a decrease in contrast), which wouldn't be noticeable in photographic applications. The effect of bubbles can be much more spectacular in laser optics though!

Cheers