Omega D super dichroic II negative carrier
I have just bought an omega D enlarger with super chromega D dichroic II head.
It came with a 4x5 neg carrier 423-363 without glass.
I do not think I can put glass in this negative carrier. Are there among you who enlarge 4x5 glassless with this enlarger or should I better lookout for a neg carrier
with glass ?
I think that most of us use the glassless carriers on Omega D enlargers with the Dichro II color head because it tends to keep the negatives relatively cool so that they don’t expand and belly upward and out of the plane focus due to heating as is likely with a condenser head without heat absorbing glass.
The Dichro II head has a UV/IR filter on the outside of each mixing chamber. The light passes through the dichroic filters and then through the UV/IR filter of the mixing chamber where it bounces around and finally passes through the bottom diffuser to illuminate the negative.
I’ve not had any negative popping with the Dichro II head and, therefore, don’t need a glass carrier as is sometimes necessary with a hot condenser light source.
Don’t overlook the possibility of using below the lens VC filters if you find this more practical in using variable contrast B&W papers. In this case, you’d leave the dichroic filters all set to zero.
I use glassless on my D-6 Pro lab condenser head and don't have any problems with negatives popping. Even with long set-up time it doesn't pop, so my seven to fifteen second exposure times aren't even going to make it pop.
Depending on how big you enlarge and how hot the lamp gets, frequently 4x5 can be safely enlarged with a glassless carrier. The ratio of the film thickness to the film size is favorable to hold pretty flat in the carrier.