Lith prints with measles

[ckagy]

I've run into a problem with lith prints and need to turn to the collective wisdom of the crowd. I am making (attempting to make) lith prints using Arista's liquid lith chemicals, and Arista EDU ultra FB VC paper. My first few batches of mixture, and the resulting prints, came out fine except for the usual beginner issues of snatch point, ect. Now, I'm suddenly seeing stuff like this:



What on earth is going on? I haven't changed paper. I haven't changed chemicals. I tried changing dilution from 1:24, and then 1:15 because I was getting REAL long developing times but still these spots. I ran my trays and beakers through the dishwasher, but I still get the same symptom.

I'm sure - well, I HOPE - others have seen this and can help me figure out what's happening. Maybe even point me in a direction or give me an idea of what I need to change or correct. Any input is most welcomed.

Thanks,
-Chris

[Jim Noel]

The spots look like chemical crystals in the developer. If the solution temperature gets too low, and it is a saturated solution, re-crystallization can happen.

[andreios]

Is it another batch of paper or same box? Foma is currently tweaking their emulsion and some batches of some papers did have these problems.

[ckagy]

Jim: I tried very hard to bump the temperature of the solution the last time I developed. I mixed the A & B solution with hot tap water. I'm diluting my lith chemicals 1:24 and, recently, 1:15 - would that be enough to saturate the solution in the development tray? I don't have crystals in my undiluted A & B solutions and they are kept cooler than development temperature.

Andreios: The paper is all from the same box.

Puzzling!!

[ndg]

I may be wrong but they look like pepper fogging spots from chaotic development. You see that when the sulfite is exhausted leading to no control of the semi-quinone. It can also be provoked by high dilutions and high temps. Some papers seem more susceptible than others. Try a totally fresh dilution, don't add any "old brown" and use a temp of about 68 deg F.

[plaubel]

I mixed the A & B solution with hot tap water.

Can you discribe "hot", please?
I drive from 20 to 25 degrees Celsius, for me that ist from normal to warm.

Here, I don't believe in chaotic development pepper corns; using Moersch chemicals, they will become black.

Arista EDU is no continious stuff, I have heard, but I have no own experience.
No other idea, than this, temperature and paper, and.like said, fresh dilutions...

[Drew Wiley]

With snatch printing in general you've gotta move quickly to make sure the developer immediately wets the whole surface of the print. I do this by rapidly but gently spreading the solution with my hands over the entire surface of the print just as soon as the print is submerged (wearing nitrile gloves of course), and it must be fully submerged immediately - then keeping a bit of agitation going in this manner during the whole brief sequence, then making a quick transfer to the stop bath and doing more of the same. This would be my guess as to what might be going wrong.

[ckagy]

plaubel: by "hot" i mean around 45C. I got the same effect with a lower temp (~20c), it just took a lot longer to show.

I'll definitely try fresh dilutions, and, as Drew suggested, ensure that the print is totally submerged immediately. I also have some Adox warmtone paper coming to try.

Thanks for the ideas, folks. I do appreciate it greatly.

[plaubel]

Maybe the "alchemist" Wolfgang Moersch fom germany has an idea, usually he is very helpful...

[ckagy]

Tim Rudman confirmed that this appears to be typical of current Foma papers and that Foma is running a new emulsion starting in April. Phew! At least this issue isn't operator error.

Everyone, I appreciate the pointers and advice. With any luck, when my new paper comes I'll have some pleasing results to share.

Best,
-Chris