Carbon Tissue Question
Okay all you carbon printers out there...I'm just getting into carbon printing after a few years elbows deep in the kallitype process.
I've ordered 200 bloom gelatin but can't wait for it to arrive. So, I mixed up some Knox stuff to make the glop. 80g of Knox went in distilled water and let it sit. Warmed it up to liquify it, added 15g of pigment (I used chunghwa ink for sumi), mixed well, added 45g of sugar and mixed well, poured in 50g of 99% isopropyl alcohol, and stirred for a few minutes. Let it all sit for an hour to dispel bubbles.
I poured the gelatin into the magnetic frame (about 1mm thickness). Let the gelatin set, pulled the frame off, and left it like that. Checked it this morning (had been sitting for about 16 hours). When I touch it, it's very cold and clammy...it's rubbery like jelly. The temp of the room is 24 C, humidity is about 60.
What is dried pigmented tissue supposed to look/feel like when it has "dried"?
Everything sounds pretty good. I assume you used a total of 1000ml water. Everyone works a little differently...I use Knox as my standard gelatin, but I use a bit over 110 grams per liter (11%), but the rest is about what I use..
Anyway, your tissue is not dry yet. Once set, I remove the tissue from where I pour it and tack it to a piece of cardboard. Then stand it upright (less chance of dust falling on it) and have a fan blowing air across it over night. If I do not use a fan, then it will still be rubbery like yours. After the fan over-night, I let the tissue air dry for a total of 48 hours before I use it. I am usually at 60 to 75% humidity, but rarely over 20C.
The surface has to be dry to the touch -- but as important, dry below the surface...which is why I wait the full 48 hours before use.
What are you using for your tissue support material? I use a material the does not pass moisture...the tissue can only dry from the one surface. If you use a pourous material, then the drying times can be a little shorter.
Thanks for your help! I guess it's not dry yet. I'll get the fan out and try that. I kind of followed Sandy King's instructions, and started off with 900ml of distilled water. I eventually ended up with a bit more than 1000ml total...
As for tissue support, I'm using Yupo, which is pretty expensive up here. 11x14 pad of 25 costs me $25 Canuck loonies.. I guess that explains why it hasn't dried yet. What are you using for support?
I am using litho film that the students toss out (already exposed, developed and fixed), or like the package of 16x20 litho film I have that is too old to doing anything else with but fix it out. It is .004" thick. I used some that was .007" thick, but had trouble getting it to lay flat in the contact printing frame during exposure. I have better frames now, so it might work. I get many many uses out of a sheet. Recycle and reuse! (I transfer onto old photo paper, too!)
You should be able to re-use the Yupo, depending if you can pour on sheets that are already the size you want to print with. I know Sandy likes to pour large sheets and cut them down -- a very efficient way, but difficult to re-use the material.
But just about any material, plastic, paper, or otherwise, can work -- as long as it does not deform in hot water or falls apart in the same. Some have used wallpaper (unglued) or that stuff they use to wrap houses with before nailing on the siding (Tyvec?)
That's pretty clever using film. I have quite a few old 8x10 sheets laying around. Hey, after fixing the film, do you remove the gelatin coating or do you just leave it?
I'm going to try spirit sensitizing. I'm waiting for ammonium dichromate to come in as it is apparently best to use with isopropyl alcohol (which I have heaps of...I can't source any acetone up here so I gave up on that)...the sad thing is that I have lots of potassium dichromate (from kallitype printing) on hand, but apparently, it and isopropyl alcohol don't work well together for spirit sensitizing...any experience with this?
Not yet, but maybe someday so I'm soaking up knowledge...........
Is there an upper limit to drying conditions? If/when I attempt carbon transfer, I will most likely be drying in my garage. In east Texas. In the summer. Garage temperature in the 80°F-90°F range. Medium humidity. Winter too, but it's cooler then. Closer to your summers.
Andrew, I leave the gelatin coating -- and I have noticed no difference between coating the image or non-image side. I have a few sheets of litho film that I hav e used 20 times or more -- but eventually the original gelatin coating starts to flake off (not surprising considering the number of times it gets put into 120F water.)
Here in the States, acetone can easily be found in hardware stores...especially in painting/refinishing stores. I buy it by the gallon (3.8 liters?) -- lasts a long time seeing how I use 14 ml per 8x10 tissue.
Strange thing about Potassium dichromate (PD) and Ammonium dochro (AD). Some folks work with PD and Iso with no problem as a one-shot tray sensitizer...and I have had bad reactions between AD and Iso (the solution would start to quickly darken). it worked fine when I first started to carbon print -- perhaps the later Iso had additives. I switched to acetone due to that...and much faster evaporation times.
Venchka -- no upper limit. After the tissues seem to be dry, one can put them in a box and/or plastic bag to keep them stable. Too dry, and the tissues start to curl excessively. One can modify the amount of sugar and/or gylcerin in drier climates to help the tissue retain enough moisture to prevent excess curling. Too much sugar and/or gylcerin can cause the tissue to always retain too much water -- risking damaged negatives when printing...and possibly poor transfers.
In my relatively cool damp climate, I actually use more sugar than most (but little or no glycerin). I use 80 grams sugar per 1000 ml of "glop". One just has to experiment and see what works best for one's working conditions and work flow. One size does not fit all with this process! But I think Andrew's receipe is a good starting point. I use much less pigment of a different type (about 4 to 5 grams of lampblack watercolor paint from tubes for 1000ml of glop).
If you really want to sponge up carbon information -- check out...
Just a quick note on the acetone...I picked some up at the Rona on Austin Ave. a couple of months ago for a non-photo related project. Is it not appropriate in someway?
You can take the information that Vaughn gives you and follow it. It will serve you well. The process does require one to find their own working parameters. Vaughn and I live in similar climates and I use 50 grams of sugar and no alcohol. With a fan on my tissues, which are thick pours, take a good two days to dry. I just switched to a 200 bloom and I noticed that it takes a bit longer to dry. So give it time. Sensitizing will depend on the DR of your negative. You can adjust contrast with the dichromate and/or the pigment in the glop. The best info is on the carbon forum. Come join in the fun over there. Much more information to be had.
My workroom is climatized all year round and the RH varies from a low of about 30% to a high of 55%, but 90% of the time it is around 40-45%. I use about 30 grams of sugar per liter of glop, and usually no glycerine. I made my tissue on Yupo and pour to a wet height of 1mm - 1.5mm, usually the latter. With a fan the tissue takes abou 24 hours to dry when the RH is 45%. At 60% RH it would probably take 48 hours to dry.
Tissue on any plastic or synthetic paper will dry at the same rate since it can only dry from one side. I used to make tissue on paper and it dried much faster, but there are more disadvantages than advantages with paper.
There are several grades of Yupo. I use the lightweight variety to make large tissues (24" X 30") and cut to size for small prints (11X14 or less), usually discarding the Yupo after use. For larger prints up to 14X20" I use a heaver weight Yupo and reuse it many times.