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zolveria
05-25-2010, 10:36 PM
Is there a way i can Place colloid on glass and place under my enlarger
and transfer that to the emulsion?

Or do i have to use a pinhole camera?

I just saw a video and I am awed... these will make nice Xmas Present for my family. :)

wildbillbugman
05-26-2010, 04:37 PM
Hi,
I do not realy understand what you are asking.. Are you asking "Can one use a Colloid plate as a contact negative? If that is your question-Of course. But the "emulsion" must be of enlarger speed.
What dose a pinhole camera have to do with this?
I think that no one else has responded to your question because it is just not clear as to what you want to do.
Bill.
Bill

zolveria
05-26-2010, 06:48 PM
What I am asking is..
When you place the colloid on the glass .. and after you bathe it.
Do you have to use a camera to expose the image to the emulsion.

What i would like to do is. expose the emulsion with my enlarger and not the camera ?

Shangheye
05-27-2010, 02:03 AM
Hmmmmm, I think I know what you mean. I thought that Wet plate Collodion (sensitized with silver nitrate) is mainly UV sensitive, so that may be a problem with an enlarger. Dry plate would be a different issue I think. K

jnanian
05-27-2010, 05:46 AM
i have made dry plates that i used instead enlarging paper, the emulsion
is basically paper emulsion ... wet plates, as kal said,
are sensitive to a different type of light ... making enlargements might be troublesome.
( and collodion is flammable ("sensitive" ) to heat. )

CRhymer
05-27-2010, 07:48 AM
Hello zolveria,

I have used an enlarger (tungsten lamp) to make wet-plate collodion on glass positives from B&W film negatives and ambrotypes from B&W film transparencies. The exposure time was 5-8 minutes, but works quite well. There are many variables, so your results will differ. I do not have a working set-up to use sunlight, as was used in the old days, and some people use today. I wanted to make images of subjects that could not be still long enough for wet-plate. Another thing to note: Wet-plate has a very different spectral response than panchromatic film, so if you use a panchromatic negative the results will look quite different than a wet-plate of the same scene. Also, wet-plate is extremely fine-grained. The enlarged image of a film negative may not have as fine a grain. Tonal range and Dmax are also factors. I did not find this to be a problem for my purposes.

If you already do wet-plate, give it a go. If not, the harder part (and most fun), is making wet plates. It is magic! (So is making silver-gelatin emulsions).

Cheers,
Clarence