Re: Some Kallitype observations
Hi Venakatram,
Thanks for sharing these results. A few questions.
1. How are you gelatin sizing in terms of percentage solution and
method of sizing?
2. What is your clearing agent, method, and time.
3. Are you mixing the potassium oxalate from oxalic acid and
potassium carbonate or buying it already mixed? If the former, what
is your mixing procedure and at what pH do you maintain the solution?
Sandy King
At 3:31 PM -0800 11/21/06, Venkatram Iyer wrote:
Hello All,
I would like to share some recent observations using the Kallitype procedure.
Papers: Stonehenge B side (STHG-B) prints better than the other
side. Sidedness was
determined by sxs comparison of marked sides.
Arches Platine (AP 310 gsm) needs less expo than
STHG-B, & yields richer, more lustrous tones than STHG-B
Graphix Vellum48 shows greater detail than AP
Gelatin-sized, formaldehyde-hardened AP and STHG-B
produce sharper prints with
cleaner highlights than unsized controls.
Unsized paper produces delicate softer prints with
subtler colors.
Graphix Vellum 48:
- pre-coat with oxalic acid
- use 2 coats of emulsion
- exposure will not produce a visible image. So pre-establish
exposure w steptab
- Pd toner >> cool browns; Au toner >> cool B/W
AP or STHG-B:
- do not need an oxalic acid pre-coat
- one thin coat works well; Dry it, equilibrate paper to room
conditions, then expose.
Emulsion:
- a 6:4 AgNO3:FO mix works better IME than the 5:5
- additives (Au, Pd or Pt) block up shads; this may be
corrected by decreasing exposure
- Steptab prints indicate that tonal separations are cleaner
when additives are omitted.
Exposure: Optimum exposure is reached when shadows print a medium-dark ochre.
Developer:
- 4% KOX develops the print slowly to a cool brown after 5'
of development. There was
no observable bronzing.
- With increasing concentration ( 5, 10 and 20% KOX),
development is rapid and proceeds to B/W, bronzing
occurs in shadows, and prints are muddier.
Toner effects depend on:
- the presence of additive in the emulsion
- sizing of paper
- possibly local factors (water composition, temperature,
humidity, etc)
- selenium toning (cheap toner!) of sized AP coated with the
6:4 mix printed in cool browns, and showed good
detail across tonal range.
I have found Sandy King's and Carmen Lizardo's Kallitype
publications very helpful.
Please feel free to comment/confirm/complement the above.
Rajul
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