Small DOT inside my lens element... what could it be?

Curious, I took an LED flashlight to peep down my 70-200 and noticed that on the focusing element, near the rim there seems to be a small spec. Its not dust, because it reflects light.

From certain angles it appears to be moisture sandwiched together.

Thoughts? Could it be an air bubble? I never seen an air bubble inside an element to properly diagnose the issue.

The last thing you want to do is start looking down lenses with a flashlight. Especially a bright, focused one. There are things in there you don't want to see. Trust me on this one. Dots, dust and other funk await - and it'll drive you mad.



Seriously though, sounds like a small metallic or glass piece if it's reflective. Bubbles are pretty unlikely in modern lens elements. Moisture, possibly. Probably just something from the manufacturing process. I wouldn't worry about it, honestly. Keep an eye on it and see if it moves or grows. If not, keep shooting.

Double Negative wrote in post #7854529
The last thing you want to do is start looking down lenses with a flashlight. Especially a bright, focused one. There are things in there you don't want to see. Trust me on this one. Dots, dust and other funk await - and it'll drive you mad.



Seriously though, sounds like a small metallic or glass piece if it's reflective. Bubbles are pretty unlikely in modern lens elements. Moisture, possibly. Probably just something from the manufacturing process. I wouldn't worry about it, honestly. Keep an eye on it and see if it moves or grows. If not, keep shooting.

Oh no, its like embedded on the surface/ inside the surface. Yea, never shine a flashlight unless your looking for trouble.

Anyone know what it may be?

man cant wait to shine a flash light in my lens now ;P