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Copying negatives - is it possible?

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Mike Wilde

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Is anyone successfully making internegatives from slides anymore? With purpose made film gone what color neg film would be best?

Duping color negs onto reversal processed B&W film would seem the only way to get really good conventional B&W prints from color negs now with Panalure gone.

The possibility of pre-flashing a duping film to cut its contrast should be explored. Bowens made a duper that had such a flasher built in, but it can also be done on double exposure.

I have about 90 out of 100' of bulk (low contrast) interneg dupe film, Ektachome SE SO366 that processes in C-41 to make low contrast negatives, and about 200' of Fuji CDUII, which makes low contrast positives that processes in E-6.

With fiddling with a home brewed first developer, or dilution or time and exposure adjustment it is possible to raise or lower the contrast of any reversal processed films.

A Macbeth target, a 31 step step wedge and access to densitometer do make the going a lot easier.

The efforts (or perhaps torture?) of calibrating these films (they come with no recommended speed or filtration now that they are out of date) have taught me a lot.

I now know about the corrective aspects of filtering, exposure, and curve offsets when plotting denitometer readings to find effective speed, and the right filtration, and development time to suit the subject without fog or crossed curves coming to play with your sanity.

I have experimented as well with reversal processing RA-4 to print slides onto currently availble RA-4 paper. It is workable, but yes challenging. I home brew a first developer, optically fog, rinse end then send it into a normal RA-4 process.

So to print slides, I would recommend perhaps fiddling with something akin to Astia and a lower contrast first developer to get lower saturation on the slide you want to print, and then reversal print the slide dupe.

The other path to cut contrast is to contact print base to base with diffusion, perhaps under your enlarger to make an unsharp mask of the correct (low density) on pan b&w film. Then dupe the slide and unsharp mask onto a negative film in a slide duper. Mask registration at 35mm slide sizes is a bitch though.

For b&w from c-41 there is a now discontinued Kodak RA-4 paper that was called Portra B&W. I bought a 12" x165' or so roll from a closing down photoprocessor, and while it does hint towards magenta in the shadows now, it still is a very viable paper to print on if the subject matter suits it.

More often these days I find myself using it for contact sheets of b&w negatives that I am backlogged on making up while I have my ra-4 roller processor fired up for making colour print orders.

Yes, you thought of reversal processing or neg to pos to recover the original c-41 image in b&w is possible.

Again I would recommend a step wedge as your target, and a willingnes to fiddle with extended development over normal to boost your effective gamma, for most c-41 negs are quite low contrast to produce a good print on b&w paper amterial if convenionally duped.

You would need to get your first generation pan sensitive dupe to expose to get off it's toe, and the time to give good contrast. Then there is the issue of getting a good reversal. The possibility of printing the first gen positive to an enlarged neg inthe enlarger onto lith film processed to low contrast repaonse ina dilute developer sould be explored, for it will aloow you to contact print your final paper print, and minimise the effect of grain growth though multiple small format negatives.

Oh, another mad darkroom project that wil have to wait for the kids to be grown up gone and my current printing backlog to be conquered.
 

Nicholas Lindan

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That's some pretty inexpensive [sheet film]! Have you used these personally? How are the quality?

X-ray film is probably the cheapest that one can find. Lots of people shoot it in-camera.
http://www.largeformatphotography.info/forum/showthread.php?t=48099

I've used the x-ray duplicating film with very good result. However, I have only contact printed the resulting negative - I don't know what the grain is like when making an enlargement from the copy negative.

Be aware you tend to gain contrast with each duplication generation. This is inevitable with any duplicating process you might use.
 
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tkamiya

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Hi,

Thank you for getting back with me so quickly. No, it doesn't have to be dirt cheap but it does need to be good. I was wondering if you have used the ultra fine duplication film. http://www.ultrafineonline.com/ulcotodufi.html

These films are incredibly cheap and I'm leery of quality aspect of it. Of course, I can just buy some and try but was wondering if you had some experience.
 

Nicholas Lindan

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eworkman

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You can get dupe film from Ultrafine, as stated above. Direct dupe was discontinued by Kodak a few years ago but can be found on e-bay, and a buddy of mine has had recent success with some outdated stuff.
I use it [xray] for contact and for projection dupes.
I used it to save a 60 - no 70 yr old neg that had faded to near-oblivion.
Dupe film tends toward two things
Long development with relatively weak developer per kodak recommendations for normal contrast
OR
Added contrast
In the case of the save I used the latter , as the original was soooo veerrrrry thin
As one would surmise, the grain came right out, but then I can print the new neg now.
[Probly the equivalent of "No12" paper]
I originally used a print [ higher contrast] developer, then changed to film developer to be able to quit hitting my head on the edge of the sink- but still shorter times than for Kodak -FJ60 I think.
If you have a good original neg you should get a good dupe.
If you have a tough original, you should, with a lot of work, be able to improve it in the dupe.
Xray dupe is noticebly slower than Kodak SO- whatever was, but usable for less-than-boilerplate negs. I have exposed to 5 + minutes- don't move, don't breathe as if you disturb the negative stage it will be visible.
I HAVE used a twostep dupe process, but that was to remove yellow stains and fungus: positive on pan film, new neg then on ortho. Worked awesomely well to get a couple of beautiful negs, whereas quality prints from the original were impossible
Xray dupe can be used under a safelight, another reason to not mess with pan films.
Long exposure times are a pain for good yet thick negs, very good negs are not a time burden.
BUT
long exposures give the opportunity to burn and dodge the NEW neg, saving pain when you really want a print.
Ortho film is typically described as low grain. If you develope carefully grain should not intrude.
The smallest negs I have duped were 120, most have been 116 and 8x10.
BUT
I would doubt very much that the native grain of 35 mm negs would be trumped by xray dupe enlargements, with the caveats of extremes note above.
 

wogster

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That is x-ray duplication film: blue tint, rounded corners - sort of gives the game away.

Unfortunately diagnostic imaging is going digital, which actually makes a lot of sense in that copies of X-rays can be sent to the specialist without requiring special shipping, this makes more sense when the specialist is in a city 3 hours away and wants to review the X-ray before the patient visits. It also means the hospital can archive the original and just forward a copy to the doctor.

In duplication though, the important thing is to get as good a copy as possible, for 35mm the best is probably a slide duplicator onto B&W film, process that for reversal and move on. For larger sizes, contact print the image onto another piece of film and do the same thing. If you want an archive copy, in case you *&^$ up the original, make a print, you can always photograph the print to get another negative.
 

Peter Schrager

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I use Fuji MI dupe film from zz medical or csx online and the prices are better than ultrafine
because you are getting a 100 sheet box.
Best, Peter
 
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