D@ glass negative carrier

[monochromeFan]

How does a person tell what side is the top? the black side or the silver side?

And whats the best means to remove tape from the glass itself

[BrianShaw]

White side toward the lamp house.

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http://www.jollinger.com/photo/cam-coll/manuals/enlargers/omega/D2%20Condenser%20and%20Dichro.pdf

[jnantz]

adhesive residue can sometimes be removed with either dish soap or something like olive oil . YMMV

[Fred L]

I find Coleman fuel (napha) to be a great adhesive remover. Apply precautions when using it but works like a charm.

[Richard Rau]

Actually WD-40 works pretty well.

[Pieter]

Actually WD-40 works pretty well.
Then you have to get rid of the WD-40 residue. I sometimes use Bestine rubber cement thinner. Nasty stuff. Wurth makes a solvent for cleaning up paint overstay, that may work too.

[Drew Wiley]

If it's just a small amount of tape residue, you can use PEC film cleaner. If a lot, soak the piece in a citrus solvent like De-Solv-It for twenty minutes of so first, then wipe that off, and if necessary, repeat, and then finally go to an all-purpose glass cleaner. No need to go to something nasty or flammable. But whatever you choose to use, wear nitrile gloves.