> A few questions regarding gelatin for alt-photo uses:
>
> 1. Specifically for carbon transfer, I am told that "hard" gelatin is
> better then "soft" gelatin. Is that correct? Why?
I assume that image durability is the primary reason, but don't really
know. I've posted before looking for information about the different
kinds of gelatins and received very little useful information.
> 2. At my friendly grocer's, I can buy Knox unflavored food-use gelatin
> for roughly $16usa per pound. Is this "soft" gelaltine? Any guess at a
> Bloom number?
I think it is medium hard. Somewhere in the vicinity of 175 bloom, but
again am not certain. I've used it, and it seems to work. However, you
do need to remember that this is comming from someone who hasn't yet made
a spectacular carbon print.
> 3. From the folks in Montana, I can buy 250-bloom gelatine for about
> $25 per pound. From the folks in New Mexico, I can buy "de-ionized
> ossein" for about $45 per pound. Specifically for carbon-transfer
> printing, is there any advantage to the de-ionized ossein versus the
> 250-bloom gelatin?
I just purchased a pound of 175 bloom gelatin from ArtCraft for $20.
Unfortunately I don't have Louis' book with me, but I believe that it is
175 bloom gelatin that he recomends. He can clafify that though.
> 4. For what photographic needs *would* de-ionized ossein be the hot
> ticket?
I have only heard Terry King speak of using this for sizing paper. I
really don't know much about the uses of this stuff either.
> I'm not so much trying to be "cheap" as I am trying to spend my meager
> income in the most-effective way. Any help would be most appreciated!
I understand. I'm in the same boat.
- Wayde
(wallen@boulder.nist.gov)