Hi, I have been experimenting with developing by inpsection and yesterday I tried some pinakryptol yellow desensetizing agent. I diluted it 1:2000 and soaked my negatives in it for 3 minutes and then rinsed before developing in HC110 1:60 using Phil Bards negative holder in a tray. According to the little information that I have about this, it should increase development time by 25%. So I increased my time by 25%also developed a step wedge to check and see if it was true, and what I found was that it did not seem to lengthen the development time at all. My negs were all 25% overdeveloped. It did seem to work as a desentisizer as I used a 20 watt bulb in my green safelight and it was only about 2 feet away from the film for about 2-3 minutes and I did not notice any fogging. I wonder if anyone else is using pinakryptol and what have been your experiencesa,and where could I get more information. I also wanted to share what I had learned as seems like it could be valuable information. Thanks for all your help.

-- Arthur Nichols (artnichols@syda.org), February 26, 2001

Answers

Where'd you get it and what did it cost?

-- Sean yates (yatescats@yahoo.com), February 26, 2001.

Hey Sean Photo formulary sells it in 100mil bottles for $4.50. with a dilution of 1:2000 it will probably last a lifetime.-J

-- josh (devil_music@usa.net), February 26, 2001.

Hello Arthur:

I am just curious, are you using Pinakyptol yellow for desensetizing film? In other words, you are able to developed by inspection with the green light (filter) on all through the development cycle? I ask this question, because I tought that the product to use is: pinakryptol green. Am I wrong?

Alejandro López de Haro

-- Alejandro López de Haro (alhr@cybercable.fr), March 06, 2001.

Pinakryptol is a family of dyes and where available in three or four colors at one time (yellow, green and white are the 3 I remember). Each of them has slightly different chariteristics, and not all of them are compatable with all of the developing agents--Esp. Metol.

-- Michael Lopushok (mlopushok@ccu.edu), May 26, 2001.

Pinakryptol was introduced by Konig and is a family of dyes - the formulary sells yellow, green and white versions. Green is said to be the least effective, can cause staining with some MQ developers but can be used as either a forebath or mixed into the developer. Yellow is more active in reducing panchromatic sensitivity and more compatible with MQ developers but can only be used as a forebath as it is destroyed by sulfite. White is used in the developer. Pinacryptol is probably preferred to older desensitizers like Scarlet N, especially for modern emulsions. Olders desensitizers also tend to stain film. Cheers, DJ.

-- N Dhananjay (ndhanu@umich.edu), May 26, 2001.