TOPSHIT PHOTOGRAPHY blog

borut peterlin, slovenia, ambrotype, Portrait photography, Wet Plate Collodion, Analog Film photography

Twist Wet Plate Collodion process at 30 °C

with 2 comments

A week ago the Fotopub Festival finished. I was a founder of the festival in 2001 and was running the show for seven years and today I’m proud to say that the level is so high I gladly enrol as a participant to one of the workshops. This year I enrolled in a workshop with Diana Lui and I was photographing river beaches in wet plate collodion. Heat is a nightmare for wet plate collodion process, but I rethought the process, made few tests and here we go, I was doing wet plate collodion process at 30°C almost business as usual at 20°C.

I’ve made several changes to the process.
1) I lowered the pH of silver nitrate bath from 4pH to 2.3pH by adding few drops of nitric acid into it (about 3 drops per 500ml should be enough, but check yourself)
2) I added more alcohol in my collodion mixture. I have alcohol on the spot and if I see it’s drying too fast I add some more solvent.
3) To my usual developer I added 25% of water and added 5 drops of nitric acid per 100ml of developer. I could add also 5gr of sugar per 100ml, but I didn’t have to.
4) when sensitizing plate in silver bath I reduced the time from 3 minutes to only 2 minutes. Mark Osterman is emphasizing that the sensibilization should be done by observation and not by time, but on the field I observe only the first plate then I do it by time. You can see when a plate is ready for exposure. If you leave it too long in the heat, you will get too much silver on your plate that will become fog during development.
5) I used water as my stop bath, but I’ve added a spoon of table salt to a liter of water. Salt will react with silver and will stop the development process immediately. It’s important to stop development fast if you work without running water and in the heat.

And that’s basically it. If the plate is perfectly exposed it should be developed for 20 seconds. I’ve learned this from Mark Osterman’s manual where he explains in details what does what in the process. I rethought and made lots of tests, wrote him a lot of questions and on the end I came up with results that are satisfying. Last but not least I owe Miša Keskenović lost of gratitude for all the knowledge he shared with me.

Have you seen my video about wet plate collodion at 0°C? HERE is the link. The same logic is behind, only fashion changes. When you understand the process you adjust the process freely to the conditions. Twist and shout the process out!

PS: This will be a supplement to my exhibition on 5.9.2013 in KKC, Dolenjske Toplice, Slovenia.
PPS: All those five steps aren’t probably necessary to deal with heat. Step number 1 makes about 60% of the effect I reckon, but with it you lose at least 2 f stops of sensibility of your wet plate collodion plate.

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2 Responses

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  1. Hi Borut, great plate the man thinking on the boat!! Thanks for all these helpful tips for “collodion extreme” I’d like to know what to do to put back the silver bath ph to 4 once you go back to 15-20° C. Thanks
    Ana (Veldhoven )

    Ana Tornel

    5 August, 2013 at 09:59

  2. Yes, that’s good question. You put half a (small) spoon of soda bicarbona in 500ml of AgNO3 and it should be about pH 6-7. DOn’t panic it will look like shit, all organic dirt will come out. Then boil it so 75% of water evaporates. Cool it down add water so it makes 500ml again, measure gravity, filter it and then dilute one drop of nitric acid in about 20ml of water, then add 5 ml of that solution and measure pH. Keep on doing it until pH is 3-4. Do it slowly, take your time, because it’s lot easier to lower the pH then raise it.
    An alternative is ammonium. Ammonium raise pH rapidly. Again dilute a drop of ammonium in about 20ml of water and then slowly add it to the AgNO3. Observe the effect of raising pH and take your time, don’t rush it. The good thing with ammonium is that you don’t have to boil it, it works immediately, but it sucks because the effect lasts only a week or two, then pH drops back to where it used to be. It depends what was your starting point of raising pH. In my case I would need about three drops of ammonium to get it back to pH4 and in two weeks it would come back to 2.3pH. #annoying!

    Borut Peterlin

    5 August, 2013 at 15:24


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