Kallitype Printing, Part 1
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- Опубліковано 26 вер 2024
- Coating a kallitype print. Kallitypes are a 19th-century photographic process using light-sensitive iron and silver compounds. There has recently been a resurgence of interest in these and other handmade photos under the category "alternative photographic processes."
Such an info dense and clear explanation. Really wish you made more videos.
So many I see are just filled with lip smacking and rambling on and on.
This is how a instructional video should be made
A few late notes:
1. To be clear, you can use 20% ferric oxalate without dilution. In the video, I'm using 27% oxalate (for platinum printing) I got on sale. That's why it needs a few drops of water.
2. I've found you can use tap water for mixing the citric acid rinse if you let it stand overnight to let the chlorine evaporate.
3. Just lately, I've found that using TWO drops of 5% potassium dichromate gives significantly cleaner whites and deeper blacks. I recommend it.
Hi Tom Great video.Do you add potassium dichromate to the developer or sensitiser?
@@michaelbermingham3559 I add it to the sensitizer
Thank you so much for the quality of this video, and not only that, the diligence to return and update with helpful notes - not many UA-camrs do that. 🙏
IMPORTANT NOTE: Arches has changed their formula for Platine paper to make it more absorbent. Omit the TWEEN to prevent your sensitizer from soaking in too fast.
Hi Bill, I’m buying 11x15” Arches Platine from Bostick & Sullivan. I use it at that size.
really helpful video, thank you.
It won’t affect contrast, just exposure time.
Do you have problems with the Scotch Magic Tape damaging the surface of the paper when you remove it? Thanks.
Yes it does. I've switched to Scotch Removable Tape. But I've also embraced the irregular edges I get with a brush, so I only tape the corners.
Hello Tom. What's the potency of the UV led light you use? Is 50w enough? Also what's the distance between the light source and the paper? Thank you!
Hi Camille, I'm using a 20 watt QUANS light I got on Amazon. It covers 9x12" at a height of 30" and my exposure time is 18 minutes. I recently found there's a 50 watt version, which is probably a better buy.
more videos please
I'm working on a video about selenium toning
@@tnp651 great
Hello, did you mix your toner? I see gold, platinum and palladium toners but sold separately. If I want to achieve a more sepia tones, do I use more gold?
Thank you
Gold toner gives a very neutral black. Palladium gives a slight sepia with a slightly less intense black. I've seen (but but not tried) selenium. It seems to give a rather nice sepia look. Rather than mixing a liter of toner as shown in the video, I now add drops of toner concentrate to just enough water to cover the print.
Hello Tom, thank you for the excellent video! May I ask what size paper you're using, and if you purchased it that size or cut it down from larger stock?
Hi Tom, so when you were preparing the paper were you continuously working under the safe lights? And why when the paper was drying did you turn off the lights? yvette
Hi Yvette,
Yes, I mixed, coated and developed under safelights until the paper was in the toner. I like to control everything I can, so I'm a little too cautious (it's a holdover from my photo-printing days). Incandescent light has very little ultraviolet; fluorescents and LEDs have more. You should be perfectly fine to work under incandescent lights as long as your exposure to them isn't too long. I've started coating under incandescents because it's easier to see where the yellowish solution is going (the yellow bug light makes it hard to see). You can do a test yourself. Take a scrap piece of coated paper, cover half of it, and expose it to twice the time you expect to have it uncovered in real use, then process it. If there's no difference between the two sides, you're fine. FWIW I took a workshop this summer at Bostick & Sullivan and they do everything under fluorescents, except they dry the paper shaded from the lights.
Hi Tom, thanks for the videos! Could you please clarify the dichromate use? Ammonium vs Potassium, sensitizer vs developer, and how much exactly. Thanks!
I'm using ammonium dichromate and I use 1 drop in the sensitizer to increase contrast ( for a 9x12" print). I also have some potassium dichromate but haven't used it yet. There's so much testing I could do! One of my video ideas is to see what eliminating or increasing dichromate will do. Stay tuned!
@@tnp651 Thanks, Tom! What is the concentration of your dichromate? And another question: why not increase the contrast of the negative? Presumably, the effect would be the same as adding dichromate. Or not?
Regarding dichromate in the clearing solution, I found this from Sandy King:
"Some small amount of dichromate is needed with kallitype, even with negatives of optimum DR, which is about 1.8, to completely clear the paper. The same is also true with straight palladium, where you need either a bit of platinum, peroxide, Na2, or dichromate to clear the last bit of stain.
As for the amount of dichromate needed to adapt the negative DR to the process, here are my figures. However, it would probably be better for you to get a Stouffer TP 45 test step wedge and test for your own conditions since the choice of paper and chemistry can change matters a lot. However, assuming a 5% solution of potassium dichromate, here is what I would add to a liter of developer for needed DR control.
Negative DR Amount of Dichromate per liter
1.8 2ml
1.6 4ml
1.4 8ml
1.2 16ml (but dangerous to go there because of grain)
These are real figures based on my work, but use them as a guide and best to test your own materials."
@@nomos3 I use a 5% solution, which I found somewhere. I hadn’t known about its role in clearing the print. Inkjet on transparency film struggles to get enough density to hold a full range of tones. Increasing the contrast of the sensitizer helps give a full-tone print.
@@tnp651 Huh... that's helpful, thanks. Just ordered some ammonium dichromate: will try and report back!
Sandy King is using milliliters, perhaps from a molar solution. Bostick & Sullivan sells the 5% solution, perhaps from milligrams of dry powder. That’d be 50 mg per liter.
I noticed the QUANS light from Amazon is also available in 100 watt. Would you recommend this over the 50 watt and what height would you recommend? Thank you!
Hi Mary, go ahead and get the 100w unit. As for distance, use an incident light meter to measure the center and edges. It doesn't measure ultraviolet, but the lights emit enough readable wavelengths that you can make relative judgements. Try for a half-stop falloff at the edges. My light at 30" covers a 9x12" print.
@@tnp651 Thank you for such a timely and thorough response. And, thank you your very informative videos.
Hi, great video, thanks for posting it. May I ask, how many watts is your uv lamp and how long is your typical exposure? Thanks!
It’s 20 watts and I hang it 30” above the contact frame. At that distance, it covers a 9x12” print without falloff. Exposure times are 16 and 18 minutes, depending on which developer I use. QUANS also makes a 50 watt unit.
Thanks! I would have thought this process would require a more powerful light source. I currently have a 100 Watt unit that I was planning on trying. I guess it will shorten exposure considerably, I also wonder if it will affect contrast... thanks for you quick reply.
So you add the dichromate directly in the sensitizing solution not the developer. Is there a big difference to adding it to the developer instead?
AMMONIUM dichromate goes in the sensitizing solution. Some developers use POTASSIUM dichromate but I haven't experimented with it.
@@tnp651 Ah gotcha. I thought the dichromate salt was not important but apparently it is. I'll look better into it. Another question if you don't mind me asking. Do you enlarge your negatives (by an internegative or reversal process) or print them digitally? My darkroom passion would like to make enlarged negatives but not sure if it's too much of a mess and the digital way would be a lot faster. Thanks.
@@stefanopassiglia I use Photoshop to make digital negatives. The kallitype process is very contrasty and the curve for it is weird. It rises steeply in the low values, then flattens dramatically for the mids and highs. It would be hard to get that response with an analogue process. With Photoshop, I can place the values precisely.
@@tnp651 thank you.
excellent tutorial! thanks
You didn’t say what your exposure time?
Exposure depends completely on different factors and your exposure will be different. I’ve raised my hanging light to cover a wider area. My exposure was 16 minutes before, and is 23-28 minutes now (depending on paper used).