ziatype and standard printing time

[banksy]

Thought I'd have a go at making some ziatype prints (in palladium), but have hit a hurdle early on. In trying to determine my baseline printing time I'm finding it impossible to get steps 1 and 2 to merge on my Stouffer (31 step) step wedge. Increased exposure time beyond a certain point (5 minutes) produces virtually no change in steps 1 and 2.

I'm guessing this is down to the self-masking effect of the process?

If so, is there a way to accurately determine your baseline printing time for this process - i.e. the time at which increased exposure yields little or no gain in density in step 1 - or is it simply a case of making a series of test strips by printing the step wedge for different lengths of time and making visual comparisons?

Thanks.

 

[pschwart]

I sometimes fine tune the result I get from the Stouffer tablet by printing a test strip with steps 1 minute apart (my base exposure is 13 minutes using BL tubes). I also use a reflection densitometer to measure the test strips. My dmax is usually about log 1.45 without resorting to double coating or other black magic.

Thought I'd have a go at making some ziatype prints (in palladium), but have hit a hurdle early on. In trying to determine my baseline printing time I'm finding it impossible to get steps 1 and 2 to merge on my Stouffer (31 step) step wedge. Increased exposure time beyond a certain point (5 minutes) produces virtually no change in steps 1 and 2.

I'm guessing this is down to the self-masking effect of the process?

If so, is there a way to accurately determine your baseline printing time for this process - i.e. the time at which increased exposure yields little or no gain in density in step 1 - or is it simply a case of making a series of test strips by printing the step wedge for different lengths of time and making visual comparisons?

Thanks.

 

[Loris Medici]

Try to establish a standard exposure time that:
a- Gives you convincing blacks
b- uses the strongest negative color that doesn't cause grain (because you'll always try to calibrate for the widest exposure scale = lowest possible emulsion contrast; doing so, you'll get the best results with digital negatives...)
c- and doesn't require an overly drastic curves adjustment (b and c are contradictory sometimes, try to balance these two...)

Of course, you still have to like the resulting print hue at the same time...

I calibrate for an exposure scale of log 2.9 (plain, unadulterated emulsion mix), FWIW.

Regards,
Loris.

 

[banksy]

Thanks folks. My 5 minute exposure gives an exposure scale of log 2.6 (for pure no-frills Palladium) - so I think I'm happy with that.

Unfortunately there's been a cold snap, humidity has dropped and I can't for the life of me get a convincing black any more - all my test prints are a muddy, blotchy brown.

The closest I've got to where I was a couple of days ago was by soaking a piece of kitchen roll in water and laying this behind the paper (Arches Platine) and in contact with it. Close (to my original black), but no cigar - and it made a bit of a mess of my vacuum frame.

I also tried suspending the paper in the stream of air from a cool mist (ultrasonic) humidifier for 20 minutes. Where the stream of air hit the paper I got a pretty decent black, but elsewhere the same old brown tones.

Will try soaking a piece of paper (briefly) in water next, and then letting it rest for a while before coating.

 

[Loris Medici]

Try to add 2 big drops of glycerin per ml of coating solution; that may help a lot!

Regards,
Loris.

 

[Ben Altman]

Problem with straight Palladium Ziatype is solarization in the blacks. So extra exposure may not help. Good technique and maybe some of the possible additives might help - a little Pt or Au. Gold increases contrast a lot, so be gentle. A touch of Acrylic medium can help, but only something that will mix with AFO - Golden GAC 100 seems to work on some papers. Experiment without the metal salt to see if it will mix.

Loris's advice is good. Try to get a consistent convincing black with the least exposure.

For humidity control I recommend a tray of warm water with a screen over it and another tray inverted over the top. Humidify face down before coating and face up after the coating has dried. Then use impermeable layers on either side of the coated paper while exposing. For cold weather I have an electric throw blanket under the vacuum frame to keep things warm. Oh, and warm the counter on which you coat.

And when you think you have it figured out, expect the next print to suck...
Ben

 

[banksy]

Try to add 2 big drops of glycerin per ml of coating solution; that may help a lot!

Regards,
Loris.

Will that help coating...development....or perhaps both?

The last time I used glycerin was to make marshmallows...yum, yum...an even stickier business than making Ziatypes (just).

 

[Loris Medici]

Glycerin is a humectant (and inert in the context of pop palladium printing), it will help to retain humidity inside the emulsion and paper...

Regards,
Loris.

 

[banksy]

@Loris - thanks, I will give the Glycerin a try.

@Ben - If I want to get consistent results, your standard humdification technique sounds like the way to do it. Cheers.

 

[banksy]

It's snow laughing matter.

Well, I'm sitting here writing this surrounded by endless prints of step wedges ... but I eventually got to grips (well, almost) with the elusive Ziatype. Soaking the paper, letting it drip dry and then air drying it before coating got me to a place where I could produce a fairly neutral print with LiPd + AFO. I'll explore it a bit more over the summer when the humidity rises and hopefully I can do away with presoaking the paper.

In the meantime I thought I'd try making some develop out Palladium prints using the LiPd (Lithium Chloropalladite) - something I'd never tried before.

Unfortunately I've hit a hurdle which I was hoping someone out there could help me with. Every print I've produced has tiny white specks of bare paper on it (see image) - just like snowflakes (very seasonal).

First the details:

Paper: Arches Platine (coated on the smooth side)
Temp. of room: c.68 degrees
Humidity: Around c.60% (I set up a cool mist humidifer in the washroom and let the paper 'soak' for an hour or so before coating)
Chemicals: 6 drops of LiPd + 6 drops of FO (for a 5x7). The FO solution was made a few days ago.
Coating method: Rod
Developer: Ammonium Citrate
Exposure: 10 minutes

Methodology:

Paper 'soaks' at 60% RH for an hour or so.
Coated with the solution using glass rod - 4 or 5 passes.
Dried in my film dryer for 5 mins on low heat.
Paper put back in the washroom to 'soak' in the 60% humidity for 10 minutes.
Exposed.
Developed in Ammonium Citrate.
Cleared in EDTA.

I've tried soaking the paper in a 1% solution of Oxalic Acid - I get a better dmax, but still those annoying white specks of bare paper. I can't figure out if this is where the emulsion has fallen away from the surface, or perhaps never penetrated the surface, or both, or something else entirely...

I thought it was maybe something to do with the way I was coating the paper, maybe the surface was getting roughened up; however I'm very careful, and whether I coat slowly or quickly, 3, 4, 5 or 6 passes, the results are still the same.

By all accounts Arches Platine is a fine paper - but not one that I've used very much at all - so I'm a bit suspicious of it.

If anybody has any suggestions they'd be gratefully received.

 

[pschwart]

I have heard about issues with Platine, but have always found it to be consistent and not fussy at all. For POP palladium I brush coat, let the emulsion soak in for about 2 minutes, blow dry with cool air for about one minute until dry to the touch, then expose. The RH in my work space is usually around 45-50%.

Well, I'm sitting here writing this surrounded by endless prints of step wedges ... but I eventually got to grips (well, almost) with the elusive Ziatype. Soaking the paper, letting it drip dry and then air drying it before coating got me to a place where I could produce a fairly neutral print with LiPd + AFO. I'll explore it a bit more over the summer when the humidity rises and hopefully I can do away with presoaking the paper.

In the meantime I thought I'd try making some develop out Palladium prints using the LiPd (Lithium Chloropalladite) - something I'd never tried before.

Unfortunately I've hit a hurdle which I was hoping someone out there could help me with. Every print I've produced has tiny white specks of bare paper on it (see image) - just like snowflakes (very seasonal).

First the details:

Paper: Arches Platine (coated on the smooth side)
Temp. of room: c.68 degrees
Humidity: Around c.60% (I set up a cool mist humidifer in the washroom and let the paper 'soak' for an hour or so before coating)
Chemicals: 6 drops of LiPd + 6 drops of FO (for a 5x7). The FO solution was made a few days ago.
Coating method: Rod
Developer: Ammonium Citrate
Exposure: 10 minutes

Methodology:

Paper 'soaks' at 60% RH for an hour or so.
Coated with the solution using glass rod - 4 or 5 passes.
Dried in my film dryer for 5 mins on low heat.
Paper put back in the washroom to 'soak' in the 60% humidity for 10 minutes.
Exposed.
Developed in Ammonium Citrate.
Cleared in EDTA.

I've tried soaking the paper in a 1% solution of Oxalic Acid - I get a better dmax, but still those annoying white specks of bare paper. I can't figure out if this is where the emulsion has fallen away from the surface, or perhaps never penetrated the surface, or both, or something else entirely...

I thought it was maybe something to do with the way I was coating the paper, maybe the surface was getting roughened up; however I'm very careful, and whether I coat slowly or quickly, 3, 4, 5 or 6 passes, the results are still the same.

By all accounts Arches Platine is a fine paper - but not one that I've used very much at all - so I'm a bit suspicious of it.

If anybody has any suggestions they'd be gratefully received.