Is it possible just to replace collodion with gelatine for tintype?

[OmerYair]

I'm about to dive into wet-plate (tintype) and wondered if it is possible to replace the collodion with gelatin and get sort of dry plate?
[Maybe a little chrome alum to harden the gelatin will be needed]

Am I missing anything? From early photography literature, gelatin emulsions seems to be faster than collodion and the only "drawback" is that gelatin is not as glossy.

 

[Mike Wilde]

From casual exposure to the process, I thought the coliodion was 'sticky', in a way that gelatin is not at room temperature.

 

[OmerYair]

I don't think the stickiness is what makes the process work (collodion does have to remain somewhat wet to make the process work).

The chemical reaction is as follows: The salts in the collodion form into silver halide sesitive to light when they come into contact with silver nitrate. After plate exposure it is normal dev/fix processes.

By replacing collodion with gelatin one can sensitize a gelatin+salts plate in the same way and use it whenever he likes without the rush before everything dries up. I think that some addition of chrome alum might be needed to make sure none of the gelatin melts during the process when submerged in any solution.

 

[Jerevan]

Check out www.thelightfarm.com, for example Chris Pattons' recipe here: http://thelightfarm.com/Map/DryPlate/Patton/DryPlatePart.htm

This is about as simple as you can get it. Also, hang out a bit in (there was a url link here which no longer exists) - the more people, the merrier!

 

[kevin klein]

Check out www.thelightfarm.com, for example Chris Pattons' recipe here: http://thelightfarm.com/Map/DryPlate/Patton/DryPlatePart.htm

This is about as simple as you can get it. Also, hang out a bit in (there was a url link here which no longer exists) - the more people, the merrier!

Actualy, that is a rather complicated and time consuming process. I have made simple good working emulsion in one day, from mixing to coating plates.

 

[Jerevan]

I usually recommend your article Kevin, but I can't repeat myself all over all the time I thought, so I took another one of the recipes from The Farm this time.

And I guess you could just speed up Chris' recipe by washing the emulsion instead of letting it sit overnight, etc. I guess anything is possible, just pick one that suits your style of working and go for it.

 

[OmerYair]

Kevin, your method seems very simple indeed. Why don't you add any gelatin hardener in the mix (glyoxal/chrome alum/...)?

Also, you write that a thicker emulsion yields better results - do you use some sort of frame when you coat or just let the gelatin flow and cover the plate like collodion?

 

[kevin klein]

I leave out the hardener so the plates can be cleaned off with warm water, if the plate is a good one I can harden it before drying.

To me, the thicker emulsion provides a better density because there is more thickness to the image. The other emulsion I used was very thin and did not give negatives to be printed out. I just pour the plate like collodion, drain, and set on a leveling table.

The last time I made an emulsion I did not use any hypo sensitiser and it worked fine, so I think that step can be eliminated.

 

[Jerevan]

Leaving out the hypo just makes the emulsion slower as far as I understand it, nothing else happens.