U of S | Mailing List Archive | alt-photo-process-l | RE: Van Dyck and Kallitype

RE: Van Dyck and Kallitype



I poorly edited my quick writing as usual.

I should've said:

Both are print-out processes. The term "developer" is technically a
misnomer in processes where the image is actually formed during exposure
(REGARDLESS OF whether it is visually different in color or density from
the unexposed area).

Hope you could fill in the capitalized phrase.

Development is chemical amplification of the latent image that is
submicroscopic in size. Silver-gelatin process is an example. In most
other processes, the purpose of the first bath is not to amplify the
image but rather remove unexposed and unreacted chemicals.

Self-masking is a different issue. If the printed out image has
significant spectral density in the region of the spectral sensitivity
of the material being used, then self-masking will be more prominent. Of
course, this is not an issue with developed-out processes, where the
latent image is too tiny to make gross change in the spectral density.

On Wed, 20 Sep 2006 11:53:40 -0400, "Sandy King"
<sanking@clemson.edu> said:
> Interesting. I was not aware of this distinction.
>
> However, there is a practical side to a POP process that comes into
> play, and that is self-masking. With processes such as salted paper
> there is considerable self-masking. With VDB the print out image is
> not as dense as with salted paper, but it is much greater than with
> either kallitype or Pt./Pd. where there is very little self-masking.
>
> Self-masking is a good thing in moderation, but in a worse case
> scenario where you try to print a negative that has too much contrast
> for the process the shadows will print in first, and then just bake
> while the highlights print in. This gives murky shadows with little
> separation.
>
> In practice, however, very few people make negatives with enough
> contrast for VDB (or salted paper or albumen, for that matter), so
> the highlights print in before the shadows are complete, which gives
> low Dmax.
>
>
> Sandy
>
>
>
>
>
>
> >On Wed, 20 Sep 2006 17:16:50 +0300, "Loris Medici"
> ><mail@loris.medici.name> said:
> >
> >>  A) You expose using sunlight since it's a print-out process unlike
> >>     develop-out Kallitype, and that's a big big plus when using
> >>     sun.
> >
> >Both are print-out processes. The term "developer" is technically a
> >misnomer in processes where the image is actually formed during
> >exposure (whether it is visually different in color or density from
> >the unexposed area).