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Enlarged Negatives In the Darkroom ??

rknewcomb

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Athens, Ga. USA
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Hello,
It seems that all I read today regarding enlarged negatives for alt processes suggests that the computer is the only way to do it. Does anyone still use an enlarger in the darkroom to make enlarged negatives for those processes that require contact size negatives? Did any people here do it the darkroom way at one time and say the heck with that when computers came out?
Sort of not looking forward to learning so much about computer image curves and rips and QTR etc.

thanks for the help.

Robert N.
 
There are two ways to do this.

Start with a small positive slide and make an enlarged negative.

Start with a small negative, make a slide and then make an enlarged negative.

It is possible to do all of this, but you must control the exposure(s( exactly to get a good result.

PE
 
One can also enlarge the small negative under the enlarger onto lith film which will produce a film positive and then contact print this film onto another sheet to produce a negative. Many years ago I used to do this.

Now I enlarge to a sheet of x-ray duplicating film. Kodak used to make a terrific duplicating sheet film but it is no longer available. I bought a box of 8x10 x-ray duplicating film on ebay. Photo Warehouse, an APUG sponsor also carries duplication film in various sizes.
 
Ultrafine online - I bought a direct dupe film, but haven't played with it much yet.

I usually do it with old lithographic film processed in a developer like pota.
 

Dan, is it a direct duplicating film? If you can would you pm me with the name of the film. I'll tell you of one I have in mind. Thanks. I'm in Everett btw.
 
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One can make a very nice black and white print, and then use a large format camera to take a copy picture of it. This has the advantage that it is very easy to comprehend the steps...
 
A few of my students have been doing this recently to prepared for a VanDyke Brown workshop we had this past weekend.

They used a product from the Photowarehouse. Exposed the "film" to the size they wished, developed in the normal manner for paper.

The exposures were long, sometimes up to 30 minutes, but it worked and the results from the workshop are very nice.
 

Ann, that's very encouraging, I have a few negatives of old that I would like to print in carbon.
 
http://www.mrfoto1.com/bargains/ind...product_id=20&option=com_virtuemart&Itemid=26

I use the discontinued Kodak 2422 aerographic direct duplicating film. It works well once you figure out how to use it and process it. It comes in 9.5 inch or 5 inch rolls. I have seen the rolls in a variety of lengths, mine are 500 feet long. I have a life time supply in sub 0 deep freeze.
I first bought it from mrfoto. Then when I went to buy more his web site was not working and I finally gave up and did a WTB in a few places and found some. You need to find the film that has been frozen in storage. It goes bad in room temp and it was discontinued quite awhile ago. When it goes bad it loses it's dmax.
The 2422 direct duplicating film is one step. Negative to negative on an enlarger with red safe lights.
Dennis
 
In principle it's easy. I've done it plenty of times for black and white as well as color output. Best if
you make a vaccum filmholer or easel that holds your copy film truly flat; and all your other setting
should be properly leveled. If you have the habit of working clean and precise it's pretty straightforward. Your interpositive should be slightly lower contrast and full scale, so all the detail
will be on the straight line of the film curve. Just requires a litte practice. FP4 or either TMax works well for this. Then you just print it. Also helps to have a glass neg carrier and good quality enlgr
lens that is corrected for reasonably close range, that is, for the degree of magnification you anticipate. What film you choose for output can be the same as noted above, unless you need
something esp big.
 
ann- what is the name of the ultrafine product??
peter
 
If you check out the May/June 2002 issue of "View Camera" magazine, you will find an article written by Bob Herbst which shows step-by-step instructions for making optically enlarged negatives in the darkroom with the idea of printing for alternative processes. If you are unable to locate that particular issue, you can go directly to his web site at www.bobherbst.com. and click on "Writings". He recommends using APHS film which is no longer available, but you can probably use litho film from Ultrafine.
 
I have been making enlarged negatives for years using x-ray duplicating film. I use Kodak X-Omat 2 film with Kodak GBX chemistry (there are probably other brands). It is as easy as making a print. Reverse the original negative -- have the emulsion up in the negative carrier. The duplicating film is a reversal film. It is very slow and remember more exposure yields a "lighter" dup and thus a "darker" print from the enlarged negative.

http://www.jeffreyglasser.com/
 
Freestyle now has a replacement for Ortho Litho back in stock. To amend my previous post, for high
contrast alt work, FP4 would make a nice interpositive, but might not build the higher gamma you
want in the final. But unlike TMax, is available in ULF sizes, albeit relatively expensively. Since I mostly work with sheet film, I make the interpositive by contact in a registered mask exposure frame.
Smaller film can be done this way too, simply by taping to a larger registration strip, or else enlarged
onto the interpositive film.
 
Curt said:
Dan, is it a direct duplicating film? If you can would you pm me with the name of the film. I'll tell you of one I have in mind. Thanks. I'm in Everett btw.
Click to expand...

Curt,

Yes, the x-ray duplicating film is direct - When developed, the sheet of film produces a positive image. The film is very slow and requires very long exposures. I tray develop it in D-72 (pretty much Dektol). For consistency I use the developer as single-shot. This film can safely be handled under safelight.

The box I have doesn't have a brand name on it. If you Google "x-ray duplicating film" you will get several sources. I have not seen the film that Photo Warehouse sells but I expect it is similar. The film comes in a variety of sizes.

As I said in my previous post, I got mine from ebay. I really looked out - no one else bid on it so I got it for the opening bid of $2.50 for a 100 sheet box of 8x10.
 

Thank you Dan, I have all the missing pieces in place now.
 
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