I am still gaining control over the paper direct positive process based on the recipe of Donald Qualls for film.
I spent the whole day taking pictures, one after the other, and developing in different conditions. I also used Parodinal again but I found out that my recipe of CSS works much better.
I reduced the amount of CSS in the developer to the half but increased the ammount of soda to the double. It works fine. I also tryed a weaker version with only 1/4 of CSS but it was a disaster. So, more or less, the optimal recipe for the developer is:
50 ml of CSS
200 ml of a sol. of Soda at 10%
250 ml water
|Pulling the string linked to shutter|
An interesting thing is that I don't need a clock to count the baths durations, all of them require counting from 1 to 100. Only the bath in just water after Sodium Sulfite should be 2-3 minutes.
I would like to use this process for portraits, but my lights are too weak for the paper sensitivity. Now I am thinking of buying panchromatic paper which is maybe more sensitive and I may use indoors with artificial light. Meanwhile, I made a self-portrait at my balcony but even there I needed 1/2 second exposure time at f/5.6.