Monday, April 18, 2016

Experiment In New Method For Intensification Of Wet Plate Collodion Negatives

  Recently I started being more and more interested in making traditional prints from wet plate collodion negatives using such processes as albumen, carbon, salt and others.  All of these techniques have different response as far as contrast and they all require negatives with slightly (or sometimes drastically) different density range.  Carbon and albumen in particular though call for a very dense negatives and sometimes it's not easy to achieve that with simply more exposure and slower development. 

  Traditionally two methods were used in order to up the range of a wet plate collodion negative after development: redevelopment and intensification.  Redevelopment is much more gradual of a process and, if done multiple times, allows the photographer to build the density to a desired degree with a lot higher amount of precision.  It is done in two steps - re-excitement of silver with iodine and then building density via pyrogallol-based developer with some added silver in it.  If one wants to repeat that step they are welcome to do so.  I have witnessed someone doing it over and over and over and over again and their resulting negative was beyond the printable range of any process known to mankind.  Even if one doesn't go overboard, redevelopment can take considerable amount of time.  Intensification, done in a traditional manner, consists of bleaching the negative with copper sulfate and potassium bromide and then bathing the negative in a weak solution of silver nitrate and nitric acid.  Intensification is quicker than redevelopment, but it's still a two-bath process and I wanted to find a one-bath method that would be easier to perform on location and would require only one extra bottle of chemistry.

  I would like to right off the bat say that I am fully aware of the following factors that I am not taking in account with the experiment described below.  First off, there are several methods of working with thinner negatives to increase contrast in the final print - masking negative, printing them with various intensities of light and so on.  So in theory it is possible to achieve a good print with negatives which have not been reworked after initial development.  In my case though I just wanted a quick way to up the contrast of a negative to be able to make albumen or carbon prints without masking, retouching, printing longer in the shade or reworking the negative with traditional chemistry.  I also know that the albumen print shown below is very far from being perfectly coated - all I really cared about while making this test was that the center of the print is even and can show the difference I was after and I think I achieved that.  One more note - the negative I made was nowhere near as dense to begin with as it could have been given proper exposure and development.  Still though, what I was after was the difference possible - doesn't matter than the neg is a bit thin, all I'm showing is what is possible with any given negative.  If it was more beefy to begin with well then intensification would have made it denser to the same degree.

  OK, with that brief disclosure out of the way I can go on telling you about my experiment.  In the past, when first starting to make negatives, I used a certain chemical to intensify my negatives that I did not want to disclose to the world because it has been discontinued by Kodak over a decade ago and I didn't want to drive up the prices on those meager leftovers that may remain in darkrooms yet to be discovered.  However, after being asked repeatedly what I was using I decided to experiment further with another idea that occurred to me before.  I thought to myself - why wouldn't a regular silver oxidizer work for this?  It would make the silver black and also essentially add to the size of the molecules by adding oxygen to them...  So here's that I did.

  I went to a local jewelry supply shop and picked up a small bottle of Griffith Silver-Black.  A solution used to add patina in various degrees to silver and other metals.  This 1oz bottle set me back a whole $4.97 after taxes!  Oh, and it's way cheaper if bought in larger quantities.

  When I got back to the darkroom I made a quick negative on a piece of glass that I scored in two places so it's easy to split later.  Exposure was 2 sec at f16 in late afternoon sun.  I probably should have actually given it 1sec only, because after 1.5min of development I saw that the shadows are starting to have too much tone and stopped development.  If I would have given it 1sec exposure I could have carried development to the usual 3min and then the negative would be really nice and dense.  No matter though - as long as I had an even negative to start with it doesn't matter what tonality it was.  

  After fixing in 20% hypo I split the negative in three.  Left side was to be the control, middle on was intensified with Griffith Silver-Black and the right side was intensified with my 'secret-sauce' toner.  I then dried my little negative thirds and printed them in direct sunlight on (yes, rather poorly-coated) albumen paper.  I think results speak for themselves.

Negative after fixing and two types of intensification

On a light table - left side is straight, center is intensified 
with Silver-Black, right side intensified with 'secret-sauce'

Three parts being printed with albumen
Left becomes right due to having to flip it emulsion-down

Final albumen print - it's quite a bit brighter in the highlights in real life,
I mean the edges are pure white, so let that be your guide

  A few cautions and notes on possibilities.  Griffith Silver-Black is TOXIC - says it right on the bottle.  Use regular caution that you should exercise anyway with chemistry - good ventilation, gloves, handle with care, etc.  Griffith Silver-Black is supposedly capable of gradually oxidizing silver to various shades desired in jewelry.  When I use my 'secret-sauce' I use it in super-diluted form (like 10 drops to 100ml of water or even less).  When I went to do the same (actually started with 30 drops per 100ml) with Silver-Black I didn't notice any change after a minute or so, became impatient and just poured some of it undiluted (from a dropper) onto the negative - the negative turned black immediately!  There's no reason I see why in theory a well-washed negative could not be taken to various degrees of intensification by using Silver-Black in a diluted form.  Another little note - with my 'secret-sauce' intensified negative seems to have a cooler bluish look to it, while Silver-Black is very neutral black or maybe even slightly on the warm side, which should facilitate higher printing contrast because of UV-blocking properties of warmer color.  However as you can see in the last picture above if there is a difference it's absolutely minimal.  What is indeed evident in that last picture that a negative that would be way too thin for normal albumen printing could be made to work very well with a simple one-bath intensification using silver oxidizer such as Silver-Black by Griffith.  

  Oh, and let me say that I have no real experience or knowledge in the particular archival qualities of the final negative.  It does seem to me though, that once silver is oxidized there's nothing else that can happen to it...  I mean it's black already, so I assume that after a good thorough wash (and maybe even varnish to protect it from scratching during printing) it should be good for as long as your grandma's blackened silver bracelet....

Griffith Silver-Black - Says POISON right on it, so treat with respect
You can see how much I used out of that 1oz bottle - barely any

  Well, I hope this has been a helpful read for those of you who wish to skip the endless redevelopment cycles and get a nice printable negative with a single, affordable solution obtainable over the counter or on good old eBay.

Anton Orlov

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