enlarging negatives for bigger prints?

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i've seen lots of talk about making larger negatives form smaller ones, is this mainly for contact printing or can this process be used to make bigger enlargements than one would normally be able to make with the original negative.... i have several 35mm negs i'd like to be able to print larger, is this possible?

thanks joe

-- Joe Holcombe (joe1013_@excite.com), July 31, 2001

Answers

Joe,

The usual reasons for making enlarged negatives are:

1. Preservation of irreplaceable images where you want to do restoration or other image manipulation; copying is for protection, enlargement is for ease in manipulation/restoration

2. Retouching, for the same reasons in 1.

3. Printing using platinum, palladium, and other "alternative" processes. These require exposure to UV and direct enlargement is impractical.

4. Incorporating dodging & burning in the negative when large quantities of a print are to be reproduced.

I don't know of anyone who does this for the simple reason of making a bigger enlargement, though you might consider it if, say, you use 2 different enlargers for the formats and the larger format enlarger has greater extension or better capability to make big enlargements.

-- Charlie Strack (charlie_strack@sti.com), July 31, 2001.


Making the enlargement you want from a 35mm negative will give you a better result than making a large copy neg from the the original neg and then enlarging from the copy neg. This is mostly because the copy neg will contain its own grain, plus the grain from the 35mm neg. And you may have to make the copy neg by photographing a print made from the 35mm neg, which gets you another generation away from the original image.

-- Keith Nichols (knichols1@mindspring.com), July 31, 2001.

I disagree with you keith, You can make enlarged negative on direct positive film and/or you can make a direct positive and then a negative from the positive. Using carefull technique and the proper materials enlarged negatives can look almost as good as those taken from large format cameras. This is a very usefull technique for those of us that use alternative procesess. Did you really think that people who print platinum/palladium prints make a print and then take a photo to make a larger negative?

-- Jorge Gasteazoro (jorgegm@worldnet.att.net), July 31, 2001.

since the smaller negative is the weakest link, the quality will never surpass that same neg., and it certainly will never get anywhere near large format quality regardless of what size you make it.

-- mark lindsey (lindseygraves@msn.com), July 31, 2001.

There might be practical reasons for making an enlarged negative. If, for instance, you were trying to make a 100 times enlargement from a tiny portion of a 35mm negative. Doing a straight enlargement with a normal 50mm enlarging lens would require an enlarger throw of 5 metres, which isn't a practical proposition in most darkrooms. If you made an enlarged 4x copy negative, then the throw comes down to only about 1.25 metres which is much more manageable.
Of course, this doesn't get you a 100 fold enlargement from the whole of the original negative. For that, you still need a big darkroom, no matter how you cut it. Even if you did the 4x enlargement onto 5"x4" film, you'd then need a 135mm lens to enlarge it further, and 25 times 135mm = 3.375 metres. A bit better than 5 metres, but not much.

With these high enlargement ratios, diffraction plays a big part in limiting the sharpness of the final print. You need a top quality enlarging lens that can be used at its maximum aperture.

-- Pete Andrews (p.l.andrews@bham.ac.uk), August 01, 2001.



Jorge: You say you disagree with me, but in fact you don't. All I say is that the best quality print from any neg comes directly from that neg. Of course, if you are employing alternative processes or have to work around limitations in your facilities, you may need to create a larger neg to get the size print you want. But the print you get, whatever its other aesthetic qualities, will not be as detailed or subtle as could be got from the original neg. At least, it's my experience that interposing generations between original negs and final prints can only degrade detail by adding grain and contrast.

-- Keith Nichols (knichols1@mindspring.com), August 01, 2001.

Keith here is where I disagree with you or maybe we are talking about two different things. 1.- If you use any type of ortho material, being Kodalith or another brand you get negligible grain in the second and third genration negatives. e.i. If I enlarge a 6x6 cm neg to a 6 1/2 X 6 1/2 INCH positive internegative and then contact print this positive to make a 6 1/2 X 6 1/2 negative, the grain generation would be only that of the 6x6 negative onto the positve, much like a print., but I assure you the new large negative will not show any more grain than it would have been present in a normal enlargement. 2.- if you make a 35 mm neg and then enlarge it to a 4x5 size and then contact print this interpositve to make a 4x5 negative then you would have no more grain than that of a print made from a 35 mm film onto a piece of 4x5 paper. It is obvious you have not put as much time and study into this as I have since I regularly make masks and contact negatives of this size. Now I will concede to you that if you are sloppy and have not done your homework, the most likely result of an enlarge negative for printing would be crap. On the other hand if you enlarge a 35 mm neg onto a 4x5 film and then enlarge the 4x5 to a 16x20 negative, well I dont know, I guess it would all depend on the technique, developer etc...but I assure you the second generation grain is negligible and would not be noticed if you are using the correct technique.

-- Jorge Gasteazoro (jorgegm@worldnet.att.net), August 02, 2001.

Kodak has an excellent book on making interpositives and duplicate negs. It's pub. #M-1 "Copying & Duplicating in Black & white and Color". I've mostly made duplicate negs for preservation purposes, but on occasion have had to make them because I could not get the degree of enlargement I needed. This was in working off old 4x5 negs, where I needed to make, say, a 20x24 and could not do it in one step without going to a horizontal set-up (still using a enlarger all the way up the column and a drop table at the lowest position.). When we have murals made, the labs tend to dupe up to an 8x10 neg off of our 4x5s, again depending on the degree of enlargement. If the neg is done as a 2 step (more control) or a one-step copy the right way, they can be very good negs....the easiest one-step dupe film for modern negs (not so hot for anything older than say the mid 50's) is Kodak's SO-136....which was slated for discontinuation this year, but has been given a second chance. You'll need a 4x5 enlarger most likely. the film is orthochromatic , you can use it under a red safelight, but it's really slow. The speed is close to Azo, so enlarging onto it can be tricky. It's a positive film, so this takes some getting used to as well. It usually runs about $40/box of 4x5. If you need any info on 2 step duping, I know a bit about that as well, and the films you can use for that are a little cheaper.

-- DK Thompson (kthompson@moh.dcr.state.nc.us), August 02, 2001.

That's 40 bucks for a box of 25 sheets/4x5....

-- DK Thompson (kthompson@moh.dcr.state.nc.us), August 02, 2001.

thanks everyone for your thoughts, i've enjoyed reading all this but i'm still uncertain, what i'm interested in doing is just getting some decent 8x10 to 11x14 prints from some 35mm negs, the problem is the negs are high speed (tmax 3200 @ 3200) and just dont hold up past about 5x7 enlargement..... i dont care if the grain gets a bit worse but i'd like to give this a shot if chances are the edges will hold together better if i make a larger (say on 120 or even 4x5) negative... have any of you done this with success? i'd love to hear a brief summary if you have

thanks again

joe

-- Joe Holcombe (joe1013_@excite.com), August 02, 2001.



Sorry Joe, but if the original is too grainy, then the final print is going to be too grainy, no matter how big an interneg you make.
Your best bet is probably scanning the negative, and selectively blurring or despeckling the digital scan before you make a print from it.

-- Pete Andrews (p.l.andrews@bham.ac.uk), August 03, 2001.

yes the grain probably will not change that much (comparing prints from the original to the contacts as long as the resulting prints are the same size, but the copies will certainly have less quality than the original no matter how big the copy is. I know when working with internegatives the big secret to better quality was pre exposure, maybe it will help in your endeavors.

At one time I worked at a pro lab for a man who used to do quality control for nasa during several of the apollo missions and he was also was a co-inventor of internegative film. through his guidance we did up to 15th generation internegs that still had small, sharp,readable type!

-- mark lindsey (lindseygraves@msn.com), August 04, 2001.


The issue was well addressed by the Linn company of Scotland, manufacturer of hi-fi equipment, many years ago. When data passes from one generation to the next, its deficiencies will not be compensated, but rather the next medium imparts its own deficiency on it.

So if the original small negative is grainy, making a large-size copy negative of it will not make the grains disappear: sure a large-format negative should be less grainy but we're talking about a first- generation image from a large-format camera. And in the process there is a good chance for the original shoulder and toe portions of the original negative to be further compressed, compromising highlight and shadow details in the final print.

-- Samuel Tang (samueltang@austarmetro.com.au), August 17, 2001.


This might be more than you wanted to know, but I noticed no one's brought up the Dan Burkholder book, MAKING DIGITAL NEGATIVES. I've looked through it, it's mainly for folks who want to do non-silver processes to have a large neg to contact print from w/o having to use a view camera. You tweak your digitized 35 neg in Photoshop in combination with an expensive program called Ice Fields that sort of random-izes pixels into "grain," and then send your results to the service bureaus that photo-litho people use, and voila, a large negative. Cool if you have the money, time, and computer savvy.

-- Lisa Kernan (lkernan@library.ucla.edu), August 20, 2001.

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