Trying Zerochrome-SbQ (PVA-SbQ)

[koraks]

Yeah, lots of white pigment - lots. 4x is a good starting point. Take it from there.

For orotones, I've so far always used gelatin with an easy-to-disperse 'gold' pigment, which really is mica (with maybe a little iron oxide?) with a truckload of dispersants added to it. Works surprisingly well. Make a gel with this pigment and then pour it like you'd pour a collodion wet plate. Again, it takes a lot of pigment to make a layer with sufficient covering power.

 

[PGum]

Consider an experiment with etched ( single side) “ frosted” glass. It might provide some extra holding for the highlights and with some “dithering” from the hills and valleys that may also help to extend that end.

 

[photo81]

Just a hello to the forum. I am very, very, very new to alt-processes and I'm working my way through all the informations I can get. I live here in Germany near the Alps and I consider me an amateur. I'm just interested in the least toxic processes with chemicals I can get her in Europe.

Just a question to this forum:

Is there a seller here in Europe where I can get the PVA-SbQ or the raw chemicals. And yes, I already stumbled across the Calvin Grear's site. And a very dumb question also: is printmakers friend the same as readymade PVA-SbQ?

Thank you for help!

 

[koraks]

Just a hello to the forum.

Hello to you too!

Is there a seller here in Europe where I can get the PVA-SbQ or the raw chemicals.

I'm not aware of it, no. You could always try and ask Kees Brandenburg (polychrome.nl)

is printmakers friend the same as readymade PVA-SbQ?

No, it's not exactly the same, but the concept is sort of similar.
Printmaker's friend is also low/non-toxic and as you've found, it's easily purchased in Europe as Calvin operates out of Spain. So I'd recommend starting there.

 

[AndrewBurns]

Yeah my advice would be to start with PMF now that it's available again. It's already mixed up for you and there's solid instructions online to help you with dialing in the process, which should give you the best chance of success.

The PVA-SbQ process is still kicking my rear-end, I've probably spent about half of my 1kg of raw PVA-SbQ concentrate and 6 months doing nothing but test prints at this stage, without ever having printed an actual photo (except for my experiments of PVA on glass).

Yesterday I tried what Calvin is currently recommending for PMF, which is mixing in some arrowroot powder and reducing the number of coats to 4. The arrowroot seems to make the hardened PVA much tougher during development, I was able to be much more aggressive during development (pouring water from 40cm high onto the print, spraying with a bottle etc.) and the pigment stayed on the page which wouldn't have been the case previously. Unfortunately I had to be that aggressive during development because the print wasn't clearing at all until before getting rough with it. Also there was a lot of staining and speckling, which I believe was caused by brushing on the top layers causing damage/mixing the previous layers. I've been using a fairly soft synthetic brush but I might try a hake brush again.

I'm also thinking I need to make my layers thicker to better resist the abrasion, particularly now that the addition of arrowroot seems to make the exposed PVA harder and so thicker layers are less likely to detach from the paper.

 

[PGum]

I'm just interested in the least toxic processes with chemicals I can get her in Europe.

Another option is diluted fish glue+ ferric ammonium citrate as sensitizer. Develop in dilute hydrogen peroxide (CHIBA process). Fish glue as bought is essentially 45% fish gelatin in water with preservatives and a small amount of TiO2 for opacifying. A few nice looking prints using this process have been posted here in photrio. Speed is relatively slow, like cyanotype but one can compensate somewhat with newer more intense UV LED sources. I should add too that the addition of starch powder will improve the layer adhesion as was mentioned by Calvin Grier for use with his PMF emulsion. I have used rice starch on occasion for this.

I have also worked with the low toxic PVA-SbQ, in a similar fashion to Kees’ and Simone’s zerochrome SbQ. I love the speed but not sold on it so far for various reasons. I won’t count it out for future use though. Calvin Grier’s PMF ( possibly SbQ-based) was already mentioned as an option.

 

[photo81]

Hello to all!

Thank you so much for the input. So I think I will give PMF a try. But at first I will go on to learn as much about the processes as possible, work me through th forum and set up my environment at home.

 

[AndrewBurns]

Here's my second attempt at making an actual photo print with PVA-SbQ, first was a dud because I tried to add a clear layer and didn't compensate for it in exposure times or something. It's a 4-layer print, all sequentially coated and exposed with a single development at the end.



And for reference here's the original photo:



During development the unexposed dark layers flaked off in big clumps which subsequently stuck back onto both sides of the paper causing some of the final speckling/staining. In the future I need to develop some kind of angled waterfall development bath so that unexposed PVA flakes have less chance to re-attach to the paper where I don't want them.

Eh I mean it's obviously not perfect but I feel that the gritty nature of the original photo suits all of the speckling and brush strokes. What I do need to fix however is the print coming out too light vs. the original. The adjustment curve I generated had the midtones and shadows getting significantly lighter but looking at this print I wonder if it went too far, I might even just make another one with a straight linear curve and see how it goes.

 

[Kevin O]

Hi folks, I found this thread because I am also experimenting with this PVOH-SBQ semi-finished emulsion from RS Emulsions. The example print that you posted above shows that you are much farther along than I am! I have been trying all kinds of different emulsion formulations and sizes. My current tests involve using dillute PVA (clear Elmer's glue) as a size, which seems to work fairly well, and introducing some arrowroot into the emulsion. An alternative that I have had some mixed success with is using a touch of xanthan gum to add a consistent body, rather than arrowroot. I feel like I'm getting closer to something workable, but very slowly. These materials are a lot less forgiving than I hoped they would be.

 

[AndrewBurns]

Hi folks, I found this thread because I am also experimenting with this PVOH-SBQ semi-finished emulsion from RS Emulsions. The example print that you posted above shows that you are much farther along than I am! I have been trying all kinds of different emulsion formulations and sizes. My current tests involve using dillute PVA (clear Elmer's glue) as a size, which seems to work fairly well, and introducing some arrowroot into the emulsion. An alternative that I have had some mixed success with is using a touch of xanthan gum to add a consistent body, rather than arrowroot. I feel like I'm getting closer to something workable, but very slowly. These materials are a lot less forgiving than I hoped they would be.

Yes I've been working at this process on and off for at least 6 months if not longer, as you say it's much less forgiving than would be ideal. I've never tried traditional gum printing but from what I've seen I think PVOH-SBQ is a lot more picky.

The biggest issues I've found have been:

• Really bad staining of the paper
• The unexposed PVOH-SbQ, despite softening, really really doesn't want to detach from the paper. But using mechanical methods to clear it off (brushing, spraying etc.) damages the exposed layers
• Brushing on subsequent layers over previously exposed layers is highly likely to damage them unless you use a soft brush, a lot of emulsion and you coat very quickly (within seconds, every time I've attempted to even out a layer I just brushed on more than a few seconds after it's applied I've regretted it!)

My current process is as follows:

• Base dilution of the RS Emulsions raw PVOH-SbQ for both clear and colour layers is 1 part to 8 parts water
• I'm using Calvin's black colour paste in my black mix
• I make up a clear mix and a black mix, the black mix is 2% black colour paste
• Each of my layers is some combination of the clear and black mixes to get my target pigment concentration
• I'm doing 4 layers, the first layer is about 0.3% pigment and the last layer is 100% black (2% pigment)
• All of the layers get 4.5% arrowroot powder
• I'm coating gelatine sized hahnemuhle platinum rag paper, hardened with a combination of TEOA and potassium alum

As I mentioned before, you have to be super quick but also delicate when brushing the layers on over a previous layer. The arrowroot seems to make the emulsion very tenacious during development, this is good in that it's hard to damage the exposed layers but it's bad in that you have to be very vigorous to fully clear the unexposed emulsion. I bathe the print in hot water, and then use a small plastic watering can full of hot water and pour water on the print from 30 to 40cm high, the impact of the water on the print strips off the unexposed stuff but doesn't damage the exposed layers.

I'm sure my current process is far from ideal, I really want to keep tweaking parameters to see if I can make it better, but on the other hand I've spent so long doing nothing but test prints I really want to spend some time making actual photo prints for a while.

 

[Kevin O]

Reading through the thread, I can see we've tried a lot of the same things, at similar dilutions and pigments, with the same results. I suppose the same results part is a good thing, since it implies consistency. The biggest issue I'm facing at the moment is what you referred to above, the need for multiple thin layers on the one hand, and the tendency for freshly brushed emulsion to melt right into the previous layers on the other, a problem that gets progressively worse with every layer you add. As I am a tinkerer but very far from a chemist, I've been chatting with ChatGPT about different processes and formulas to try. Tomorrow I'm going to attempt to isolate the development of layers by coating a sheet of mylar, exposing through the carrier, and transferring to a paper final support, sort of like a single transfer carbon print. The LLM is very confident that this transfer is possible under the right circumstances, although I'm less confident, given how well some of the other suggestions that it has given me have worked out.

 

[AndrewBurns]

Reading through the thread, I can see we've tried a lot of the same things, at similar dilutions and pigments, with the same results. I suppose the same results part is a good thing, since it implies consistency. The biggest issue I'm facing at the moment is what you referred to above, the need for multiple thin layers on the one hand, and the tendency for freshly brushed emulsion to melt right into the previous layers on the other, a problem that gets progressively worse with every layer you add. As I am a tinkerer but very far from a chemist, I've been chatting with ChatGPT about different processes and formulas to try. Tomorrow I'm going to attempt to isolate the development of layers by coating a sheet of mylar, exposing through the carrier, and transferring to a paper final support, sort of like a single transfer carbon print. The LLM is very confident that this transfer is possible under the right circumstances, although I'm less confident, given how well some of the other suggestions that it has given me have worked out.

I'd also be extremely skeptical that you could transfer these layers, they'd probably be in the single-digit micron thickness when dry.

My current thought is that thicker layers will show abrasion damage from brushing and rough developing less but are also more likely to flake off/detach during development. The arrowroot makes the exposed layers a lot stronger/more tenacious, so maybe the arrowroot would allow for the use of thicker layers that show damage less.

Also as you say the earlier layers suffer more cumulative abrasion while the top layer doesn't see any brushing abrasion. So maybe the quantity of arrowroot in each layer could be varied (more in the first layer, less in the last) to make the print robust enough to survive brushing but also soft enough to develop without such 'strong' methods as I'm currently using.

 

[Kevin O]

I was actually able to get some transfer, in a really patchy and unpredictable way, from polyester film to PVA sized watercolor paper. With a ton of testing and figuring out the right conditions, I believe it might be possible. The more I work with this stuff, the more I feel like there's just one control element that's missing, but I don't know enough about materials to be able to figure out what it might be.

 

[BePan]

I spent the last 3 days of the Christmas break to do some test using SBQ.

• I use a work solution of 1 SBQ with 2 H2O (SBQ for RSemulsion - Semi finished) and 6% Arrowroot
• paper HPR, sized with hardened gelatine and an exposed clear coat.
• Initially I diluted the SQQ with 2 parts of PVOH (glue) but it stick nicely to the paper after development so I continued just with work solution 1+2.
• Using a stouffer wedge I determined the exposure time for a 4 layer print (density = 1.8). In my case 50 units (which is roughly 36 seconds). Subsequent layers have an exposure time that is roughly the half of the previous layer.
• Pigment is Wet Print Black.
• Determined the maximum blocking color using Peter Marhr’s tools.
• Tried to find the correct pigment loading per layer. I noticed that it makes a difference what surface area you use, or better how you apply brush strokes. For now it is 0,42; 0.9; 2.2 and 4% (SBQ)
• I did 2 test. One applying the 4 layers and exposing them. I development at 35°C at the end (same technique as for Print Makers Friend), and one test with a development after each layer.
• The 1 development technique worked very well.
• Updated the pigment loads to 0,38; 0,ç; 1,8; 4%SBQ respectively which gave me 5 stops.
• Next I need to determine the correction curve and do my first print.

Some insights/toughts

• Working with 1 development gives a much better result (less to no staining and not so grainy). The tonality range seems almost the same in both cases.
• There is some banding on the Stouffer wedge print. I think this is due to the exposure time. Layer 2 and 3 will probably need an exposure time that is a bit longer.
• consistency in brushing will make a difference on the end result. Making brush corrections once the paper is coated (even if still wet) is useless. The emulsion dry’s quickly and you can easily break the layer.
• What I find strange (according to what I can read on various sources) is the relatively long exposure time (using an 800W halogen lamp). I think this is due to the wavelength needed to harden the SBQ, 325-365 nm and my lamp peeks at 395nm
• I have no correct idea of what the concentration of SBQ is in the Semi Finished emulsion. No technical nor safety data-sheet can be found.
• Before applying a layer the emulsion needs to be stirred. The arrowroot sinks down and emulsion with lots of pigment also have a tendency have pigment at the bottom.
• Layer 3 and 4 will probably need some additional water because they are more viscous.

 

[AndrewBurns]

Very interesting and good results.

You're using a much thicker emulsion than me (1+2 dilution, while I use 1+8) and also slightly higher pigment loading, which I would have thought would result in a much darker print, but maybe your brush technique is different?

You're getting good clear whites which I currently am not, which might be due to your use of an exposed clear coat in addition to gelatine sized paper (I currently use hardened gelatine sized HPR but no clear coat).

I have been thinking about moving to a heavier coating to see if it would make it harder to damage previous layers when brushing on later layers, could be worth a shot. As you've noticed brush technique seems to be critical for this process, you really only have a few seconds to brush a layer on and if you come back to 'tidy up' a layer you've let sit for even a few seconds you ruin the print. It's very unforgiving...

 

[BePan]

@AndrewBurns I tried to match my Pigmentloads to specific lightness (LAB) values. I used those from Calvin Gries's exposure calculator for a 4 layer (Density of 1.8). I come close to the target values.

In my experience the clear coat makes a difference.

And yes, the brushing is the tricky part. You need a good brush that can distribute the emulsion evenly. The brush hairs need to be soft but not to soft. You also need to do it correctly within 30 seconds. If a bruch stroke is OK, don't go over it again.
Now it seems doable because of the size of the paper. My intention is to go to ful A3+.

 

[Kevin O]

I got some dry pigments today, and instantly had much better results. Previously I had ok results with some but not all brands of India ink, and bad results from tube watercolor. I attempted acrylic ink too, but it's not water soluble, so a complete failure. The emulsion is extremely sensitive binders and additives in pigment mixes. My current formula is RS emulsion diluted 1:4 with distilled water, a bit of pigment powder, and a drop of isopropyl alcohol. It doesn't solve the brushing issues, but I am getting very consistent results and no staining with two clear coats, followed by a coat or two of pigment, and a fairly full exposure (one minute with my 150W "blacklight"). I'm now getting the results I expected previous to many many hours of testing.

My next steps are working towards better emulsion brushing behavior, and working out development that requires less brushing.

 

[BePan]

Getting close. Managed to get a curve (that needs some tweeking, the midtones are a bit flat) that workedout ok. (bottom without, top with curve)

 

[BePan]

My next steps are working towards better emulsion brushing behavior, and working out development that requires less brushing.

I'm also not satisfied with the brushing of the emulsion.I expected the stripe marks you get from brushing would flow away ( the /\/\/\ would become ____). but it doesn't. It's also hard to control the tickness of the coat.
Anyone experience with rollers?