glass plates, how do you print them?

[trudee yama]

Been asked if I could print glass plates? Have only printed film. Any suggestions would be greatly appreciated...good websites, books to research. Types of paper, chemicals, timing, do I even use an enlarger? And if so, how? Or, a business that still prints plates. They have all been archivally stored for decades, each in their own archival casing. Sizes range from 2"x4" to 8"x10". How do I handle them without disturbing their integrity? Can I clean them with an air can? This is exciting for me as I've never even really seen a glass plate before. Probably way over my head, but would love to try.

Trudee

 

[John Shriver]

I scan them on a flatbed scanner. Space them the right distance from the glass on a scanner with transparency adapter, and scan away.

They were generally meant to be contact printed, and you will probably find they have high contrast and high Dmax.

If you want the work done commercially, look at the places on the approved list to do this sort of printing from negatives in the Library of Congress collection. (They now outsource printing, but only to approved vendors.)

 

[fschifano]

You know, I've done it and treated the plates just as I would an normal film negative. My enlarger will accommodate negatives up to 4x5 inches and the plates were slightly smaller than that. I made a temporary negative holder with an appropriately sized opening from some rigid cardboard and just went at it. The negatives printed rather well on variable contrast paper with a filter that gave about a grade 2 equivalence. You can also make contact prints very easily. No need for a cover glass since the glass plate itself will likely hold everything in close contact without any additional pressure.

 

[keithwms]

You're not in over your head, not at all.

I think you will want multigrade paper. Other than that I think you'll find them quite similar to normal negs. I recently printed some myself and it was all pretty normal. The plates I have been using were well coated and are quite difficult to scratch; nevertheless, it is easy to leave fingerprints, so... wear gloves. Forced air would be a good way to clean them. Perhaps the underside could be cleaned more vigorously with rubbing alcohol, but the emulsion side... I am not sure, I'd keep liquids away from that- if there is emulsion damage it'll probably have started at the edges. It'd be nice if you had one to experiment with.

Anyway, it's probably going to be pretty straightforward. Enjoy!

 

[nworth]

Carefully. Enlarging is a bit difficult, since holders for plates are no longer made. But you can make do by adapting a piece of pressboard (or even heavy mat board), cutting a hole of the appropriate size. The glass will stay flat, in any case. You will probably make contact prints mostly. Modern printing frames are mage for ordinary negative thickness, and they could break the plate. The plate is not heavy enough to keep heavier papers flat, however. I would put the plat on top of the paper and a piece of 1/4 inch plate glass on top of the plate. The enlarder can provide the light source.

 

[David A. Goldfarb]

Start by making some contact prints, printing minimum time for maximum black to get an idea of the density range. They may be printable on conventional enlarging paper, but older plate negs are often very high in contrast and might do better on Lodima or using a handcoated process.

 

[removed account4]

hi trudee

i used to print glass all the time.
just stick it in to your enlarger and enjoy yourself
i use a durst m601 but i take the negative carrier out
and just stick the plate in the head and use a cloth to block the
light from coming out of the big slot.

bigger plates enjoy yourself contact printing them

have fun!

john

 

[Rolleijoe]

I've always treated glass negatives the same as film (when it comes to exposure), however, be careful not to crack the glass. I've a sizeable collection, and once the electrics are repaired for the darkroom, can start printing on that lovely Foma 542 paper.

 

[yellowcat]

Some museums in the UK will have facilities to print from glass plates.

 

[Ian Grant]

As John and Joe have said just use an enlarger for the smaller ones and contact print those that are too large.

It also depends on the age and type of emulsions/developers originally used. With some negatives the only way to get a decent print was with POP papers because or their self masking properties, this was the way many museums etc made new prints until very recently. I printed for a museum in the early 70's, and another alternative is to make a reduced inter-negative (copy) from larger glass plates.

Ian

 

[jfish]

If your enlarger will handle any of the sizes, simply get a piece of glass bigger than the plates that will fit in your enlarger and use that to rest the plate on in your negative state. Use black tape around the part of the glass plate holder that the plate does not cover to block out the light that will go through it, as you will get paper base fog/increased density and flatter contrast otherwise. For the 8x10's you'd need an 8x10 enlarger of course unless you just contact print them. As for a lab that does it, I do and in the past have done Imperial plates (8x12") for the Oakland museum, but I got rid of that enlarger years ago. Located in Atlanta, GA.

Hope that helps

 

[Martin Reed]

This probably won't be an issue, as they're not particularly large, but something to watch out for is the orientation in which the plates were stored. Glass, being a supercooled liquid will flow given enough time, and if stored horizontally without support may sag a little, rendering the plate liable to crack if pressure is applied.

 

[Anton Lukoszevieze]

Yeh, small plates in the enlarger, larger plates contact print. I sometimes enlarge my smaller collodion plates, amazing blemishes.....and detritus, hyper-ortho too.

 

[edp]

Glass, being a supercooled liquid will flow given enough time

This is a widespread misconception, and entirely false.

Which is lucky, given the ages of some of the lenses in use today.

 

[David A. Goldfarb]

Indeed the explanation for why the glass is thicker at the bottom of an old window is that glass wasn't always of uniform thickness, and if you were a glazier, it would only be logical to install the glass with the thick end on the bottom.