Public Lab Research note


H2S strip batch 1 for testing made 4/26

by sara | April 27, 2012 17:43 | 2,638 views | 3 comments | #1817 | 2,638 views | 3 comments | #1817 27 Apr 17:43

Read more: stable.publiclab.org/n/1817


Megan and I made a batch for testing the H2S strips last night. We made 66 strips in all. We could only make 1 batch as we ran out of drying space in the dark room. Some of the strips stuck together and had to be discarded. They are to be marked with red dots so we can compare strips made with this batch of Ilford paper with strips made from a second batch of Ilford paper. We hypothesize that the results will vary slightly between batches of Ilford paper depending on the quantity of Silver Halide in the paper. They were made with Ilford 8x10in Multigrade IV RC DE LUXE photo paper. Catalog number 116 8310. Cut into 8x2 inch strips.

Notes for future strip making: 1. The Photoflo 200 is diluted in a 1 drop to 200 ratio. We noticed that 2004 Horwell article doesn't actually document the volume of 50/50 water to glycerol ratio. So we tried 3-4 drops of the photoflo for the 700 ml of the 50/50 glycerol/water mix we had. 2. We reconfirmed that glycerin is synonymous with glycerol 3. We added 5 grams of salt to this mixture. 4. We learned not to put lots of strips in at once as they then all stick together. Probably in the future for making large numbers of strips the volume of starting solution should at least be doubled. 4. Drying the strip on large scale requires a ton of space. I think we need to rig up a stacking system to dry them on. 5. The strips require longer than 12 hours to dry. Unfortunately I had to pack them up in paper towels while they were still a bit damp because other users were planning on making use of the darkroom. 6. We will be using round button stickers (red) to mark this batch of strips unfortunately the strips were too damp to afix the stickers to this morning. We will take care of that next week.


3 Comments

did you take any photos?

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No! Great thought though we'll photo document the process of making batch 2.

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as much as possible given we're working in a dark room and so can't use the flash

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