Mottling (pepper fog?) when lith printing with Moersch SE-5 onto Fomatone 532-11

[atomicthumbs]

Howdy all. I'm working on a final project for my alternative processes class involving lith printing onto the aforementioned paper (bought fresh from Freestyle for the project), using a digital negative printed on acetate film. My aim is to develop a cyanotype-over-lith combo process (and maybe just do some lith printing if that turns out to look terrible).

This is my first time lith printing, and I was running into an odd mottling issue that wasn't apparent at first, but that seemed to affect my prints more as the afternoon went on - see pictures.

In progressive exposures (as I nailed down my exposure time; lighter prints are later in sequence), I noticed this occurring and tried adding solution D (bromide restrainer), then diluting the developer, then adding a little more D and some C (sulfite something or other), then mixing it with the less-used half. I was doing this over 4-5 hours in a small tray that could hold one 5x7 print, and it was about half full. I used 500ml of water and 12.5 of each developer to start out with, and added another 500ml when diluting. Temperature was 20c plus a couple degrees or so. Exposure time turned out to be ~1m at either f/5.6 or f/8 (can't remember which).

Is this due to developer oxidation from sitting out, exhaustion from me developing ~5 5x7 prints (the first two being way overexposed) in that small amount of developer, or another variable that I'm failing to take into account?

Photos of photos (click for big):



Any advice to a new lith printing initiate is greatly appreciated!

 

[mooseontheloose]

How long was the paper in the developer? There are plenty of examples of this problem on the lith printing Facebook page. From what I gather, newer batches of Foma paper tend to have this problem (I've seen examples from 131, 132, 542II) - some people call in the snowball effect, others the leopard print pattern, some mottling, like you do. One suggestion is that reducing B and increasing the temperature (up to 30 C) might help, as the latter at least would reduce the amount of time the paper is in the developer.

 

[Photo Engineer]

This is not pepper grain. Pepper grain is more like someone shook pepper onto the print. This might be called a mottle and can be either process or coating related.

PE

 

[atomicthumbs]

tried reducing B, no D, ~25-30 degrees, results okay. found new exposure times: 16 minutes at 5.6 instead of 60 seconds. tried with normal B, good results, same time. added D, good results, more time. not a paper problem.