old glass negatives

[Jim Jones]

Bethe -- you have enough information above to do the job. Go for it. Amateurs have usually preferred film for the past 100 years. Many pros used glass plates until much later. Even when they were originally intended to be contact printed, the camera work could be first-rate. Thus, there was photography of remarkable quality done on glass plates. The opportunity to work with them is illuminating. Of course not all photographers made the most of the medium, but it is still worthwhile volunteering for the job.

[Sparky]

They should be fine for contact printing. The place you might run into issues is trying to enlarge them. In an enlarger, you run the risk of the emulsion catching fire and exploding (if they are wet-plate negatives). Later dry-plate negs might just crack and flake off the glass from overheating. The safest thing to do is either contact print or scan and enlarge that way.

Hey - how do you figure they risk fire or explosion. To my recollection - that has ONLY to do with nitrocel film bases. Glass, in my experiences tends not to spontaneously combust...

[seawolf66]

I am in the process of unpacking some stuff that has been stored for a long while and I ran accross Two Plate Positive's , Which I am not familuar with any thoughts on these positive Plate fotos!

[Ole]

Positive plates are called "Lantern Slides". Look it up.

[TheFlyingCamera]

Hey - how do you figure they risk fire or explosion. To my recollection - that has ONLY to do with nitrocel film bases. Glass, in my experiences tends not to spontaneously combust...

If they are made with collodion, they ARE nitrocellulose based. Collodion is a form of nitrocellulose. If they are later dry plates, then no.

[mcgrattan]

We scan a lot of glass plates at work [I work in a studio that deals mostly with old manuscripts, I'm the IT guy though, not a photographer].

We have one to do soon which is about 3ft across. I did a few experiments just placing larger plate negs on a lightbox and photographing from above. The results were surprisingly good.

[Sparky]

Really? Okay... hmmm... I stand corrected. Didn't know it. However - there would be absolutely NO danger of anything exploding unless it were in a sealed container of really small volume and the decomposition rapidly proceeding - which probably wouldn't be happening by now - I'm guessing that any major changes to the emulsion would have been happening in the first 20-30 years... but hey, weird things happen.

If they are made with collodion, they ARE nitrocellulose based. Collodion is a form of nitrocellulose. If they are later dry plates, then no.