PDA

View Full Version : Modern ambrotypes



robopro
11-11-2006, 01:35 PM
Just posted this question in another thread. If using a handmade gelatin emulsion on glass, what's the best method for developing? Also, is it possible to use a direct positive silver development process with a gelatin emulsion on glass to produce an ambrotype effect?

PHOTOTONE
11-11-2006, 11:21 PM
Traditionally an Ambrotype is a wet-collodion emulsion coated on a glass plate, sensitized and exposed in the camera while still wet, processed while still wet and then fixed and dried. It is really a thin negative image, but due to the type of developer used results in a negative image that has a rather light tone to the developed silver, and when backed by a piece of black paper or velvet, appears as a positive. There is no reversal, or direct positive type of processing done, it is just the color of the developed image is lighter than the black backing behind the glass plate is darker, making the developed image appear as a positive (by optical comparison to the background).

robopro
11-12-2006, 08:36 AM
I know. Been doing some searching on how to recreate that effect with modern emulsions and have found modern tintype kits but no information on how to do an ambrotype with either albumen or gelatin. Maybe it can't be done with modern emulsions?

Photo Engineer
11-12-2006, 09:08 AM
It can be done with handmade emulsions, as they are not 'modern emulsions' in the strictest sense and can create very low contrast images. This is just what you need for Ambrotype I would think.

PE

PHOTOTONE
11-12-2006, 09:56 AM
I know. Been doing some searching on how to recreate that effect with modern emulsions and have found modern tintype kits but no information on how to do an ambrotype with either albumen or gelatin. Maybe it can't be done with modern emulsions?

There are plenty of people who are doing Ambrotypes and Tintypes (same process on black japanned tin) the traditional way. There are texts available and workshops you can attend, and resources for the supplies needed. Why would there be a need to replicate the results with a gelatine emulsion, when you can do it the "historically correct" way?

Kerik
11-12-2006, 12:41 PM
Why would there be a need to replicate the results with a gelatine emulsion, when you can do it the "historically correct" way?Plus, the collodion process is lots of fun...

smieglitz
11-12-2006, 02:04 PM
... Why would there be a need to replicate the results with a gelatine emulsion, when you can do it the "historically correct" way?

Formica vs. wood, vinyl vs. leather... "Nudge, nudge, wink, wink. Know what I mean? Know what I mean?"

The convenience of silver gelatin "tintypes" comes at a great cost visually. If you try the commercial product on glass, you'll probably have to sub the plate to get the emulsion to stick. A silane or albumen solution might work.

As Kerik has related, real wetplate collodion is much fun, but inconvenient, and you have to respect the chemistry. IMO though, it really is unmatched in terms of visual qualities.

Joe

robopro
11-12-2006, 03:18 PM
There are plenty of people who are doing Ambrotypes and Tintypes (same process on black japanned tin) the traditional way. There are texts available and workshops you can attend, and resources for the supplies needed. Why would there be a need to replicate the results with a gelatine emulsion, when you can do it the "historically correct" way?

Because I'm doing pinhole photography in 11X14 format and use exposures of 40 minutes to 3 hours or more, thus wet plate collodion is not an option for me, and I have no plans for putting a lens on my camera just yet....
I suppose it is possible to do a contact print on glass and put a white or gray board behind it. Wouldn't look the same but might be interesting.

robopro
11-12-2006, 06:35 PM
OK,

Here's a photo I did today. It's an 11X14 pinhole with a 127mm focal length. I shot it on an albumen glass plate negative with a 1 hour exposure time, and then did a contact print on another albumen plate, developed normally in gallic acid, and painted the back of the glass white.
It works, but it aint no ambrotype...
The actual photo is not quite as sharp and is a little lower in contrast, and the scanner I used can't quite get an entire 11X14 so some detail around the edges is missing. Also, when I enlarge the scan there are a series of lines in the upper left hand corner that aren't on the print.

htmlguru4242
11-14-2006, 07:31 AM
Maybe not an ambrotype, but that looks pretty good; that's on a homemade albumen plate?

robopro
11-14-2006, 08:29 AM
The scan looks better, trust me! I think it did some auto correcting or something, and it didn't get the edges so you can't see the marks made by the clips holding the negative in the camera. I also think one reason it doesn't show the uneveness of albumen on paper is that it is on glass so there was no 'absorbtion' problems. I also used masking tape to make a shallow 'tray' out of the plate which allowed me to get a more even coating cuz I didn't have to worry about the albumen dripping off the edges, and I used 4 coats instead of the 1 or 2 you would use with paper. I just wish I could get my exposure times down -- at 1 hour this one was actually fast! I hate to think what's going to happen when I increase the focal length on my new camera...

robopro
11-14-2006, 08:44 AM
To give you an idea of the variation in quality I'm getting with albumen, here's another one I made last summer printed on Kodak paper. Don't remember the exact exposure time (I need to start taking notes), but you can see it's a lot darker (meaning the negative was lighter) and lower contrast. Also there wasn't a cloud in the sky so the variations you see in the sky are from the albumen. I don't really like this photo so I never made a second print, but if I did I think I'd lighten it up a little.

htmlguru4242
11-14-2006, 10:17 AM
Robopro; this is quite interesting, and albumen is something that I've wanted to try; i think that itd be an interesting entry into emulsion making.

Would you mind sharing some of the details on how you make the plates, or point me in the direction of some good information?