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View Full Version : Back to the future-what about glass plates?



David F. Stein
14-Apr-2001, 18:23
I have been doing a fair amount of scanning and inkjet printing of old glass negatives-4x5 and larger. It sure doesn't take a super-duper APO MULTI-COATED 17-ELEMENT COMPUTER-RAY-TRACED lens to produce an exquisite image. Large neg size and, I think, the dimensional stability of glass plates go a long way. Anyone worked with the TMax 100 glass plates that are available? May be interesting, given all the film register, bowed and slipped film issues surfacing lately.

Here's an example, but no means the best image I've worked with: http://members.aol.com/forgeniuses/GLASSY/Ed.jpg

TH

Joshua L. Slocum
14-Apr-2001, 23:51
Hmmm. . neither does it take a SUPER DUPER DIGITAL 4000 DPI SCAN0- WIZARD system to make a nice print:)) My I ask why you chose to print this way David? If it were me, I would have opted for the tonal range and fidelity of a contact print made from these beauties. Scanning and inkjet printing cannot come close to reproducing the qualities of these plates.

Just curious

Oren Grad
15-Apr-2001, 00:33
David - It seems to me that, given the cost and fragility of glass plates, the Schneider Hi-End back, which purports to control the flatness of 4x5 sheet film to within 0.1mm, might be a more practical solution for high-precision applications. Is there anyone here who can report on actual experience with the Schneider back?

Sal Santamaura
15-Apr-2001, 01:14
Oren, I can't give any first hand feedback, but thought it interesting to note the other day that Schneider's web site no longer mentions the Hi End Back system. Could be that lack of sales has led to that product's discontinuance.

william blake
15-Apr-2001, 12:48
Glass plates are a special order item at BH --- VERY expensive. If your goal is to increase resolution, rather than shoot 4x5 glass plates, I'd cheat by shooting 8x10 film and enlarging less. Probably cheaper in the long run (I'm thinking 100s of pictures), even if you factor in the cost of a used 8x10 enlarger...

David A. Goldfarb
15-Apr-2001, 12:56
Yes, I've had that thought too. TMX plates are astoundingly expensive, I presume because they are produced mainly for scientific use.

On the other hand, if you're inspired by 19th-century uses of glass plates, there's no reason you can't make them yourself just like they did. I would guess that you can even get flatter glass than they had. There are a few sites around the net about collodion photography, typically associated with the Civil War reenactment movement.

Marc
15-Apr-2001, 13:56
Having made prints from hundreds of glass plates ranging in size from 2X2" to 8X10" I can attest to thier quality. For what ever reason the old plates can make very beautiful prints, as alluded to by Josh. Although the print exposure times ranged from f32 at 1/2 second to f5.6 at 7 minutes, 90% of all of the plates I printed made prints that rival any made off of a modern negative. When the exposures were right on the prints have a depth that is amazing.

That being said, having read exposure times off of the negative sleeves,(f22 @ 1/10 second in BRIGHT sunlight for example), I wouldn't give up the modern emulsions speed. I had one batch that even had street addresses of buildings, unfortunately in the intervening years the city fathers changed all of the addresses in that area so it takes some researh to compare them to todays buidings.

If you ever get the chance to print from some of these negatives it can be an interesting history lesson. One set even had a couple of pictures of the photographers darkroom dating from around 1900, funny he never did show his enlarger!

Oren Grad
19-Apr-2001, 23:33
Sal, the pages on the Hi-End back were still there on the Schneider web site as of my last posting (April 14). But they were well-hidden - I had to dig into the section on LF lenses to find any link to them...

william blake
20-Apr-2001, 13:40
For what ever reason the old plates can make very beautiful prints, as alluded to by Josh.

One factor might be that glass makes a clearer, flatter base than plastic film. I worked with a couple different roll films before I settled on Agfapan as my standard. I don't believe that Agfapan is the absolute best film for everyone and every application, but I found it's tone curve to be among the most pleasing to me when printed on a quality paper. I notice that Agfapan seems to be made out of a clearer, more flexible base than other films like Verichrome Pan(which I also like alot) or Tmax, which seems to make Agfapan easier to damage when processing...comparing similar negs from Agfapan and Verichrome, I find it easier to make prints that please me from the Agfapan - I wonder if the clearer base helps?

I saw prints by August Sander about 6 months ago and was quite taken with the print quality -- I wonder how much of that is from the glass plate and how much of that is the quality of his printing paper? The prints were certainly as tonally rich and detailed as anyone could wish --- I understand that Sander made his images with a 19th century uncoated lens without shutter -- he just took the cap off to start exposure and put it back on to end exposure. He prefered a rather slow orthochomatic glass plate. I think the results speak for themselves.

Just curious -- do the Kodak Tmax glass plates require a special holder? If the glass is thicker than film stock(and surely it must be) it wouldn't fit under the rails for loading and wouldn't focus be off by the thickness of the glass plate.

kthompson
20-Apr-2001, 16:02
David, William and the rest of you all, I agree that there is a nice quality to the tonal range of a glass plate printed onto an older emulsion--POP, or even contact paper for that matter. While I have never used the TMX glass plates, I know they have been made for years, along with several others for scientific/technical photography purposes. I don't know if it's still in print, but Kodak has a book (Pub. P-315) "Scientific Imaging With Kodak Films & Plates" that covers these extensively. I am in no way an expert on conservation issues, but while a glass plate itself (as long as it isn't cracked obviously) is more stable than acetate base or nitrate film, the emulsion suffers in the same ways that all other films do. It is my understanding that cycling conditions can stress a glass plate emulsion in many ways, and since the base is not flexible, this puts even more strain on the emulsion. So, just assuming that the glass plate is "dimensionally stable", is not all there is to it. If you all are collecting older plates, you may want to look into some of the conservation sites for tips on storage, as they have special needs. Good luck...

Pete Andrews
23-Apr-2001, 11:59
In answer to William's question -"do the Kodak Tmax glass plates require a special holder?" : Yes, they do. You can't just slip a plate into a modern plastic DDS.Plateholders have a lip under which the plate is loaded against the pressure of one or more light leaf-springs in the back of the holder. This holds the emulsion in absolute register, unlike the sloppy method adopted by modern filmholders, where the emulsion position depends on the thickness of the film base, the camera position, the phase of the moon, and whether there's a 'R' in the month.