Printing from old glas negs??? : LUSENET : Large format photography : One Thread

Does anyone have any experience making projection prints from old glass negs (5X7 from around 1890)? I may have to produce a fair amount of prints from old priceless negs. this summer and wonder how they might print on AZo - or Platinum?

-- Per Volquartz (, March 26, 2002


Neither Azo nor Platinum can be printed by projection without a carbon-arc light source on your enlarger. You are going to have to either contact print or use some other paper.

-- Wilhelmnn (, March 26, 2002.

I do understand that platinum has to be contact printed.

I would prefer to be able to make silver prints. The glass plates have a very long scale. That's why I thought of AZO. My enlarger - an 8X10 Durst with a 12X12 340 watt Aristo cold light head puts out a ton of light...guess I will have to try to find out for sure...???

-- Per Volquartz (, March 26, 2002.

Greetings Per,

Give AZO a try. I've used it to enlarge 4x5 negatives (print size 8x10) using an Omega Dichro II light sorce. My print times were in the 5 - 8 minute range @ f8, but it worked. It sounds like you have much more light output in your enlarger and you're starting with a larger negative. If you have the time, it wouldn't hurt to try. Good luck!

Regards, Pete

-- Pete Caluori (, March 26, 2002.


I have printed from some 4x5 glass plates that belonged to a friends grandfather, I made a cardboard holder for the plate and used my enlarger, printed on standard multi grade paper. I have one RR 5x7 glass plate was planning to do a contact print only with that one.


-- Bill Jefferson (, March 27, 2002.

If they are might want to consider duping them and working off the dupe negs instead....depending on the age & condition of the glass plates, handling them alot & the associated risks of long exposures etc. may not be too good for them.....the glass can get fragile & brittle with age, and the emulsions can sometimes flake off....if it were for preservation, you might want to either make interpositives and then contact dupe those onto sheet film, or make a working master print by contact onto Azo or POP....then make the best copy neg you can and work off that. Working off old originals can sometimes put them at risk....MY opinions only as always.

-- dk thompson (, March 27, 2002.


Some ideas from my experience printing glass negs from the turn of the century a few years ago.

First, glass negs are VERY fragile. Handle them with extreme care. Sometimes the spring tension of the negative stage in the enlarger is enough to crack one. Making a negative carrier out of sturdy cardboard that has a recess for the glass to fit in is a good idea. That way the glass itself does not get clamped.

I also found that many of the negs I printed needed cleaning. Standard film cleaner will work for some things, however I ended up washing several negs in water. An hour or so in the archival film washer worked well, but again, make sure they stay separated in the washer and that you have a suitable rack to dry them in. Before you wash, check to make sure the negs were not retouched. Many portrait negatives from this period were routinely retouched with pencil and fim cleaners and washing will remove the retouching graphite. I found that the character of the faces i.e. wrinkles etc. were much more to my liking than the smooth retouched look and removed most of the retouching. However, if these are not your negs or have historical significance, I would leave well enough alone.

By far the largest problem I had was retaining contrast in the prints from these extremely long-scale negatives. Most glass negs were designed for POP and are very contrasty. I found that low contrast grade paper coupled with a dilute soft working developer, e.g. Selectol Soft, produced acceptable results most of the time. For extreme cases you can dilute the developer even more and/or use a water-bath technique similar to the technique used for film developing. I would dunk the print in the developer for 30 seconds with vigorous agitation, then transfer it to a water holding tank and let it sit without agitation for two minutes. This cycle can be repeated until the desired contrast is reached (you have to be able to evaluate the print under safelight). Your "developing time" is then the number of cycles.

That said,I would also recommend duping the negs to reduce handling if you need to make more than the occaisional print or if the negatives are priceless records with sentimental or historical value. Standard contact duping procedures should work keeping the high contrast original in mind and altering the developing time accordingly.

Hope this helps, ;^D)

-- Doremus Scudder (, March 28, 2002.

Hmm...I work in a museum and it's been hammered into me to always leave the original alone & treat with the utmost care & respect........I'm not a conservator, just a photographer, but I believe that rewashing any old negs or prints is a bad idea....I can't even touch or handle an item with gloves on, and in some cases I'm not even allowed to be left alone, much less touch an item...and I've been here for 10 yrs. Our conservators would probably kill me if I were to rewash a print.....

just my opinions here though.

On that note, I suggest you contact a state or local run archive, and try to find one with a paper or photo conservator on staff. If you can't find one of those, even an objects conservator may be able to help you. Here's a couple of websites to try as well....

that one is about care & handling & history of wet & dry plates. This next one is to the Chicago Albumen of the few commercial labs in the US that does historical printing and neg/plate duplication and preservation. They are also the distributor for Centennial POP as well as some Agfa dupe film products for this type of work....

This is a good overview of preservation theory & practice from the NEDCC:

I don't know what country you're located in, but again I would suggest trying to find some advice from a professional conservator before attempting to clean an old neg or glass plate yourself....some things are better left alone....If you do try to do it yourself, make the best dupe neg or copy print you can _before_ touching the original neg.

Opinions expressed in this message may not represent the policy of my agency

-- DK Thompson (, March 28, 2002.

."I can't even touch or handle an item with gloves on,"

correction: should be "without gloves on"....

-- dk thompson (, March 28, 2002.

Oh yeah, if you want some info on two-step duplication, here's something from the National Archives.

Opinions expressed in this message may not represent the policy of my agency

-- DK Thompson (, March 28, 2002.

Hi Per

What about scanning them with a very good flatbet scanner then use Photoshop for the cleaning part and burn it on CD for new negs or positives? And you still have the original for comparison.

Good luck.

-- Armin Seeholzer (, March 30, 2002.

Moderation questions? read the FAQ