Exposing old glass plates

[Como]

Recently I found some very old unexposed glass plates. Kranz Ultra Ortho 18/10 DIN 9x12cm. Probably 90-100 years old.
I intend to use these plates in my grandfathers camera.
Has anybody experience in developing these plates? Is there any chance in succes?

Kind regards, Como

 

[Nodda Duma]

Check to make sure DIN speed still means the same today. I think it does but double check.

Add about 5 stops exposure and tray develop under red safelight in HC-110 dil B at a cold temperature like 60F. Watch for image / fog to form and pull before the fog gets too bad. Stop and fix (about 5 minutes in rapid fixer)

 

[Nodda Duma]

Test expose on a bright sunny day in natural lighting too btw

 

[Como]

Thanks Nodda Duma, I will give it a try.

 

[JPD]

The DIN standard for emulsion speed was published in 1934, so the plates can't be older than that.

 

[JensH]

Hi,

go for it, it's fun and the results can be stunning!
Give them a lot of light, 3 asa or below.

I exposed vintage glass plates and nitro films (6.5x9cm) made in the 1930s in a microscope camera (Zeiss Miflex). See here: https://www.flickr.com/photos/136145166@N02/albums/72157686135321996

Developed in Rodinal 1:50 at 18°C, some plates were fine, some quite foggy.

Best
Jens

 

[Como]

Found a table on internet which compares ASA, DIN and Scheiner

 

[Como]

When developing old rollfilms I have always presoaked it for ten minutes in water before using developer.
Should I do the same with these old plates?

 

[Nodda Duma]

Might be a good idea

 

[JPD]

Found a table on internet which compares ASA, DIN and Scheiner

DIN 18/10º is today 50 ASA, but 40 according to that table. I wonder which one changed? But the difference is just 1/3 of a stop, and you'll need to give those old plates a bit more exposure anyway.