Dupe Negative/ Internegs????

Hi I've got a question concerning dupe negs/ internegs:

I have some really important 120 B&W negatives that I need to make copies of. I'm not really sure what the best way to go about that is in an analogue format. I know I could scan, but that's not what I'm asking. I need them to be high enough quality that I can make prints from them.
Is it possible for me to do it myself, or is better to have lab do it? Is it going to cost me a lot of money? Will the new negs be good enough to make prints from?

Thanks!

Good Afternoon, Expfilm,

Some years ago, Kodak made a film specifically for duplicating negatives. It was called Professional B/W Duplicating Film, SO-339. You might, with extremely good luck, locate a long-frozen box of it by checking E-Bay. Otherwise, consider making the best print possible and copying to get a new negative. Labs tend to charge quite a bit for a simple copy job you can do quite easily yourself.

Konical

I'd also recommend just duping a master print, preferably on a larger format than the original.

Another option is to make an interpositive using ortho film or a relatively linear film like TMX (again larger than the original) and contact printing it to another sheet of the same film to make the duped neg.

It is possible to dupe negs in one step using reversal processing, but the contrast characteristics may be different from the original. dr5 offers this service at dr5.com.

There's a continuous tone, direct positive ortho graphic arts film available from ultrafineonline.com

No experience with it yet (although it's been mentioned before here so someone's used it) but it's fairly cheap so I daresay it's worth a try...

I make enlarged and copy negatives using both the inter negative (actually inter-positive) and direct positive methods.
Ther is much greater control of density and contrast using the inter-positive process. My preference is APHS from Freestyle for both the positive and the new negative. There is a thread on APUG concerning this process where if I remember corrrectly, I spelled out my process as to developers, etc.
The importatn thing to remembver is to make the inter-positive very flat so there is detail in both higholights and shadows. It is then possible to make the new negative with any desired contrast and D-max.

I would consider making a 4x5 interpositive on edupe (with a very slight enlargement).
I think it would be higher quality than the neg from print.