Ambrotype on dry plate?

[TheFlyingCamera]

Can Ambrotypes be done on dry plate glass? or do they have to be done with wet-plate collodion?

 

[JG Motamedi]

You could produce a dryplate ambrotype using collodion, with coffee or tannin as a preservative, and developing it in pyro. Works fine, but really slow.

Wondering about those plateholders?

 

[Wayne]

slower than normal?


Wayne

 

[JG Motamedi]

slower than normal?

yes, about two stops...

 

[TheFlyingCamera]

I was up to visit Rob Gibson's studio in Gettysburg over the weekend, and was looking at how neat the ambrotypes are. I've got some 5x7 dry plate holders I'd be interested in learning with, and I just don't want to go through the hassle of getting another entirely new camera, with all the attendant wet plate gear.

 

[Wayne]

that speed loss could be a real killer. What is the practical speed of a wet plate- 1? 1/2? Just wild guesses, but I'm sure someone here knows.


Wayne

 

[JG Motamedi]

I generally shoot my portraits at 1 second at f/4, on a good day the meter says 12.66ev on skin. So, maybe .25 ISO?

jason

 

[c6h6o3]

I was up to visit Rob Gibson's studio in Gettysburg over the weekend,

Where else did you guys go?

 

[Wayne]

I generally shoot my portraits at 1 second at f/4, on a good day the meter says 12.66ev on skin. So, maybe .25 ISO?

jason

Well heck, then you're only looking at a few seconds or so for dry plate portraits. Thats doable, and thats what I'd like to try someday.



Wayne

 

[Donald Qualls]

For whatever it's worth, the ambrotype effect (scattering from the silver image showing as positive against an absorptive black background) is perfectly operant with gelatin emulsions; I know of no reason you couldn't make ambrotypes with dry gelatin plates (some purists may claim the gelatin emulsion won't look just like the collodon, and they might be right, but developing with collodion chemistry would be a good start).

From what I hear, though, don't trust the Rockland Colloid "tintype" developer; it's bad about as often as it's good, and their (gelatin) tintype emulsion (which would also work for ambrotype) is too expensive to waste that frequently...

 

[htmlguru4242]

I'd imagine that it'd work. Some of my regular negatives (Tri-X, etc.) that are underexposed show the "ambrotype" posibtive effect when placed on a black background. You could definetely do this well if you tried to refine it ...