Re: VDB is "Brownprint" process?

Hi to all. I'm replying to a message by Sandy King (posted in January
2003).
 
I was reading C. James' book and noticed the section about "Brownprint".
Since I had all the ingredients in hands, I mixed the sensitizer and
made a test (after 24h ripening period - filtering the sludge before
use) just to see what happens. (Sensitizer was mixed as following: 2.5gr
green Ammonium Iron(III) Citrate + 0.5gr oxalic acid + 20ml water, mixed
well, added 10ml 10% silver nitrate, mixed well, ripened for 24 hours
shaking occasionally - please notice that the amnt. of oxalic acid is
25% more than what the formula given in the book dictates).
 
Paper: Bergger COT 320.
 
Darkroom humitidy: 45%
 
Coating: 1 coat, 5 mins. flat drying (letting the emulsion soak into the
paper). After the initial 5 mins. drying, I hanged the paper and dried
it further 20 mins. - blowing cold air with a fan.
 
Exposure: Using a 31-step tablet (log 0.1 steps), 6 mins. with 8x40W
Philips bulbs placed 1.5" above frame glass. When I took the test print
out of out the frame, there was a relatively strong print-out; steps 1 -
16 were showing density (step 17, no density). Step 1 was merged with
the surrounding clear area, step 2 was slightly lighter than step 1,
step 3 was slightly lighter than step 2... and so on. Color was light
"cafe latte". Dmax was weak.
 
Development: 2 dessert spoons of Borax into 1lt tap water, 2 mins. When
I poured the "developer"(!) on the freshly exposed print, (previously
clearly discernible) steps 1 - 10 merged to dmax, previously white steps
17 - 20 started to show density (step 21, no density). No perceptible
dmax change occured.
 
Clearing: 2 dessert spoons of Citric Acid into 1lt tap water, 2 mins.
Dmax weakened, unexposed but coated sections of paper cleared
successfully.
 
Fixing: 2 dessert spoons of Sodium Thiosulfate Pentahydrate into 1lt tap
water, 1 mins. Dmax sligthly increased (better than dmax rigth before
exposure). But still weak - slightly weaker than single coated Vandyke.
 
After Drying 8 hours: There was 2 steps dry-down effect in the
highlights and dmax improved considerably. But it's still weaker than
single coated Vandyke.
 
In short:
 
1) It's not true that the process is a DOP. I got a very strong
print-out.
2) Exposure time is very short: If my calculations are correct, with my
setup, 45 secs. exposure will be enough to reach dmax!!! (Since steps 1
- 10 were dmax with 6 mins. exposure, 1/3 x 9 = 3 -> 2^3 = 8, 6 / 8 =
0.75 -> 45 secs would be still enough for step 1 reaching dmax - please
correct me if I'm wrong here!) This is very fast when compared to my 8
mins. Vandyke standart printing time (for double coated paper) with the
same lightsource and frame.
3) Density is weak compared to single coated Vandyke (will try double
coating this evening).
4) Color is different compared to Vandyke; it's less red, a milky-brown.
Vandykes are reddish brown.
 
That's all for now. Will try double coating tonight.
 
Sandy don't get me wrong, I'm replying to your message because I found
it while making a research just before mixing the sensitizer - I find
appropiate to include my experience along with yours for the future
archive searches.
 
Regards,
Loris.
 
  _____

From: Sandy King (sanking@clemson.edu)
Date: 01/04/03-12:37:06 PM Z

This message has a comment and a question.

First, the comment. On p. 167-68 Christopher James describes a
process he calls the "Brownprint." The difference between this
process and regular VDB are said to be that 1) it uses oxalic acid
in place of tartaric acid, and that 2) development is in a mixture of
borax and water rather than in plain water. It is also stated that
after proper exposure there is a "stage whisper" of an image as in
kallitype, which suggests that the "Brownprint" is a DOP process and
not POP like VDB.

OK, I mixed the sensitizing solution as per James and tried his
"Brownprint." The results were very disappointing. Sensitivity was
very much less than what one sees with VDB, about two full stops.
Also, I tested development in both plain water and in the borax acid
mixture and there was no difference at all. Finally, the image before
development was much more similar to what one sees with VDB than with
kallitype.

If anyone else has tried the "Brownprint" process as described by
James and gotten good results I would be interested in having some
details of your work.

Next, the question.

In all of the previous literature at my disposal, including Dick
Stevens' book on the kallitype, the term "Brownprint" is used to
describe a form of printing that most of us understand as VDB. That
is, the sensitizer is based on ferric ammonium citrate, tartarid acid
and silver nitrate. Does anyone know the historical origin of James'
use of the term, which differentiates it from regular VDB?

Sandy King
Received on Thu Feb 23 05:47:07 2006