Re: Some Kallitype observations
Hi Sandy,
A minor correction: Venkatram is my husband.
Gel sizing: I make a 4% solution of Knox gelatin, add ~1 ml HCHO/25 ml
gelatin and a dropper full of Everclear, pour 5 ml of this on to
thoroughly wetted paper (in lukewarm water) that has been drained and
set on a warm microwave oven plate. The size is spread with a sponge
spreader with a wooden handle (hardware store).
Clearing Agent: I use ~4% citric acid. After development, the first of
2 clears is poured on sans
washing off the KOX, a short wash follows; then the second wash. Each
wash is for 5'.
KOX: I use the salt as sold. I have not checked the pH.
Rajul
On 22-Nov-06, at 6:18 AM, Sandy King wrote:
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
|