From: John Campbell (tojohn@texas.net)
Date: 03/04/03-11:17:33 PM Z
Hello, Richard. . . ?
----- Original Message -----
From: "Liam Lawless" <liam.lawless@blueyonder.co.uk>
To: <alt-photo-process-l@skyway.usask.ca>
Sent: Tuesday, March 04, 2003 10:52 PM
Subject: RE: C-41 in b&w chemistry
> John,
>
> Yes, sure you'd get a stain along with the developed silver, but it'd
still
> be a thin neg. (C41 films don't contain a lot of silver, so there'd be
> correspondingly low staining.) Colour couplers are used in chromogenic
> toning (where they're properly known as colour formers); maybe modern C41
> films use different couplers, but some of the ones I've used in toning are
> alpha-naphthol (blue), 2-4-dichloro-1-naphthol (cyan), nitrobenzyl cyanide
> (magenta) and acetoacet-o-chloranilide (yellow). Don't know the chemical
> formula of pyro stain (is it in Hutchings?) or of the dyes that are
produced
> in C41, but the colour coupler formulae don't look anything like that of
> pyro.
>
> Maybe you should ask Richard :)
>
>
>
> Liam
>
> -----Original Message-----
> From: John Campbell [mailto:tojohn@texas.net]
> Sent: 05 March 2003 04:43
> To: alt-photo-process-l@sask.usask.ca
> Subject: Re: C-41 in b&w chemistry
>
>
> Greetings, all--
>
> Okay, I'm gonna pitch in here, even though it's a bit premature.
>
> Over a year ago (if memory serves me) I accidentally loaded (meaning I
paid
> no particular attention) and developed several rolls of B/W C-41 along
with
> several batches of TMX and developed the lot via Pyro. I recall being
> mortified/curious/delighted with the results. I edited and printed
several
> of the C-41-Pyro's and thought they were quite nice. Then I dismissed the
> whole affair as anomaly and went back to paying attention.
>
> . . . until this thread came up.
>
> And since this thread came up (and reminded me of events from over a year
> ago), I've been searching (or intending to search) for those C-14-Pyro
> negatives.
>
> (I'm sure I have them somewhere. . . . )
>
> In the meantime, my question for Liam is: Might Pyro stains take the place
> of the C-41 color dyes? (. . . and might they be related, chemically?)
>
> . . . and my question for Keith is: Why do you ask?
>
> With delight,
> John
>
> www.photogekco.com
>
>
>
>
>
> ----- Original Message -----
> From: "Liam Lawless" <liam.lawless@blueyonder.co.uk>
> To: <alt-photo-process-l@skyway.usask.ca>
> Sent: Tuesday, March 04, 2003 4:26 PM
> Subject: RE: C-41 in b&w chemistry
>
>
> > Keith,
> >
> > The C-41 emulsion contains three layers of silver halides and colour
> > couplers. Oxidation by-products of silver development combine with the
> > couplers to form the C, M and Y dyes, after which the silver (thinner
than
> > in B&W film) is no longer needed and is bleach-fixed away to leave just
> the
> > three dye images. Or something like that.
> >
> > With a straight b&w developer, the coloured dyes do not form and you end
> up
> > with just a thinnish silver image. Plus, I think I read somewhere, the
> > unused couplers contained in oily globules, which I believe can be
removed
> > (with alcohol, perhaps?)
> >
> >
> > Liam
> > -----Original Message-----
> > From: Keith Gerling [mailto:keithgerling@att.net]
> > Sent: 04 March 2003 19:06
> > To: alt-photo-process-l@sask.usask.ca
> > Subject: OT: C-41 in b&w chemistry
> >
> >
> > Can anyone here explain what would happen if C-41 film happened to be
> > processed in chemistry intended for black and white film?
> >
> > (no, I didn't actually DO this. Just curious)
> >
> > Thanks!
> >
> >
> >
>
>
>
>
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