Comments from the previous article system:
By David A. Goldfarb - 04:58 PM, 09-21-2004 Edit Rating: None
Full image--
http://www.photo.net/bboard/image?b...oad_id=17789684
Detail at 3000 dpi--
http://www.photo.net/bboard/image?b...oad_id=17799884
Thought I'd post a link to a scan from my first coffee neg over here as another point of reference. Base fog/stain is high, so I've got some banding from the scanner, but I'd say it's a printable neg, maybe grade 3 or so. Efke PL100 4x5" at EI 80 (my usual EI for PMK), orange filter, f:11-1/2, 1/10 sec. Developed 20 minutes with constant agitation in a tray (too small a tray--I burned the edges and cropped a bit in PS to compensate for the extra edge density), fixed in TF-4 to avoid pinholes from the combination of the carbonate and acid fixer, but I still got one or two. The result is a very crisp negative (grainy as well), not unlike ABC pyro but with less contrast due mainly to the base fog.
By gainer - 04:37 PM, 09-23-2004 Edit Rating: None
Has anyone tried NoDoz or other caffeine tablets?
By titrisol - 12:58 AM, 09-25-2004 Edit Rating: None
caffeine tablets? not that I'm aware of.
In one of the discussions we had it was agreed that it was not the caffeine which acted as a dev agent, but the caffeic acid (similar to pyro-gallol) which is one of the tannins present in coffee and that are taken-out in pills.
By VoidoidRamone - 03:51 AM, 09-25-2004 Edit Rating: None
Does anyone have any starting times for APX 100 and Pan F+? These seem to be the only films I've been using recently and I wanted to try this caffenol thing. Any help would be appreciated, thanks. -Grant
By gainer - 05:46 AM, 09-25-2004 Edit Rating: None
Well, I tried NoDoz and you are right. It is not the caffeine.
By titrisol - 02:11 PM, 09-25-2004 Edit Rating: None
Sorry grant, I tried APX 400 and after 45 minutes th eimage was extremely thin.
I'd give APX 100 at least 45 minutes to 1 hour.
And do not use cafenol hot (over 35C).... the stain becomes so strong that it is almost impossible to print anything.
By Murray@uptowngallery - 08:12 PM, 09-25-2004 Edit Rating: None
Wow - I've got to try this.
If it works for film, it ought to work for printing too, right?
Maybe I missed part of the preface to this posting, but does such a developer need stop bath and fixer?
Thanks
Murray
By Murray@uptowngallery - 08:14 PM, 09-25-2004 Edit Rating: None
Oops, sorry, I see something about TF-4 above.
Is there somewhere on the web I can start at the beginning for this process and it's options?
Thanks
Murray
By Jordan - 03:17 AM, 09-26-2004 Edit Rating: None
Murray, look through the photo.net archives and also do a Google Groups search for "caffeinol" or "caffenol", especially posts by Donald Qualls.
It seems like the most promising "candidate" for the developing agent in coffee is caffeic acid, which is a catechol derivative (catechol is also called 'pyrocatechol' in developer formulae). Not the same as pyrogallol, but the chemistry is related. There are probably other polyphenols in coffee that are doing similar work.
By Jordan - 03:17 AM, 09-26-2004 Edit Rating: None
Murray, look through the photo.net archives and also do a Google Groups search for 'caffeinol' or 'caffenol', especially posts by Donald Qualls.
It seems like the most promising 'candidate' for the developing agent in coffee is caffeic acid, which is a catechol derivative (catechol is also called 'pyrocatechol' in developer formulae). Not the same as pyrogallol, but the chemistry is related. There are probably other polyphenols in coffee that are doing similar work.
