how to take pics of the insides of lenses

[darinwc]

i have a enlarging lens that I am returning. It was advertised as clear but shining a light through it shows a considerable amount of haze and spots.

I would like to document it so the seller wont balk when I return it.

however I am having a heck of a time photographing the inside.

Does anyone have suggestions for how to accomplish this?

 

[ic-racer]

i have a enlarging lens that I am returning. It was advertised as clear but shining a light through it shows a considerable amount of haze and spots.

I would like to document it so the seller wont balk when I return it.

however I am having a heck of a time photographing the inside.

Does anyone have suggestions for how to accomplish this?

A few weeks a go I did this same thing to return an enlarger lens with "cleaning" marks (from cleaning with sandpaper it looked like ).

I held the lens up to a light in the basement ( I use spotlights) and aimed the view throught the lens at the dark ceiling. That way the marks on the glass show up a white on black. With the other hand I snapped the pictue with a digicam on macro. I used manual to bracket the exposure to get one that shows a good the marks very well. It was actually quite easy, and I did a comparison lens and emailed both pictures to the seller.

 

[Q.G.]

In theory, what you can see, you can take a picture of.
So the way to do it is to put the camera where your eye is/was. May require macro-equipment.

 

[darinwc]

I was able to get what i needed.

I used the tip from ic-racer. The glass surface of the lens was reflecting much of the room. (white ceiling, white bookshelves, brass lamps). That was one obstacle. I ended up using a black card to mask out the reflections.

Then I used a focused beam from a LED light to illuminate the inside of the lens.

Finally I found i had to use manual focus so the camera would stop focussing on the front of the lens and focus exactly on the imperfections.

Thanks all.