Friday, June 02, 2006

First Cyanotypes

Friday I had two packages arrive - one with fancy platinotype paper (designed to be used for platinium prints) and later in the day one with two kinds of much cheaper watercolor paper. I have a third kind of watercolor paper coming - basically to try out different textures and see how much of a difference the thickness makes and so forth.

The basic approach is to take a sheet of paper, 11.5 x 14.5 in this case, and take a little solution and draw a line down one side of it. Then you take a glass rod and smear the yellow-green fluid across the sheet, hopefully coating it evenly. Obviously this takes a bit of practice, including knowing just how much fluid to use.

Then you let it dry an hour or so, and you have a sheet of paper that's sensitive to UV light.

If you then take a large negative (the same size of the print) and place it on top and expose it to a UV light source (in my case, the sun) you can see the light areas of the negative turning blue. The print looks kind of nasty at this stage because it's a combination of the blue image and also the original yellow-green fluid. You then rinse the unexposed yellow-green fluid out of the paper (and leave it for 20 minutes to be sure it's all gone) and it looks pretty much like a cyanotype. I say "pretty much" because you let it dry for a day and it actually continues to mature.

Now, there are some different things you can do, including there are some optional chemical tricks instead of just using a water rinse, but that's the basic idea. It also turns out that there are dozens of ways to make prints that have the same basic pattern - so some skills like how to spread goo evenly on paper are the same even if you're making platinum prints.

The first thing I needed to do was to get some idea what exposure would be right for my bottle of chemical, the sun here, the density of my negative, etc. So I coated one sheet, let it dry, and cut off three strips of paper. I exposed these for different amounts of time and rinsed them and determined that about 45 seconds was right. I then took the remaining paper and exposed that at 45 seconds, it being large enough to actually have the image look like something.

You can see I didn't do a great job of getting the coating even, but hey, looks like a picture! OK, needs work, but at least I know I mixed the chemicals correctly and so forth.

One thing I noticed was that I was basically just holding the negative onto the paper and a bit of wind blew it during one of the test exposures and that strip was way less crisp than the others. So one problem was how to hold the negative and paper together.

I then coated another whole sheet (coating more even but the surface wasn't level and there's a dry patch in one corner) and tried another picture. To hold the negative down I tried just the simple sheet of acrylic that came with the sunprint kit. Maybe a bit underexposed but otherwise OK. One issue is that the whole mess was very difficult to hold without covering part of the image and you can see the edges of the acrylic in the image. Not good. I'd upload a picture of this one but it's too big for my scanner - I guess at some point I'll either have to get a larger scanner or just take pictures of them so people can see what the completed items look like.

So I took some sheets of cardboard and made a poor man's contact print frame. Basically this is one sheet for the base, another with a hole the size of the image, and some tape to make a hinge. So it makes a nice sandwich that's easy to keep together. I exposed a sunprint using this method as a check (those are proving very helpful if I just want to try something without going through the coating/drying process). It works very well! A really nice contact print frame would have a glass top (there are issues about if you want your edges to be sloppy and handmade or not, and my cardboard tends to trim those) and a real hinge so you can actually open it and close it and not mess up the alignment. Once I open mine, I'm done, I can't just pop it into the light for another few seconds.

Just then the watercolor paper arrived. Two types - I tried one of each. I did pretty well on the coating but one paper has a very strong texture and it clearly isn't going to work with this. And while the other image looked great it lost a lot of blue in the rinse (or it faded? basic paper can do that apparently). I have three ideas on how to fix this but that paper also happened to be relatively lightweight and it isn't drying very nicely - it has some curl. So I'll have to fix a variety of problems to use that paper.

I may wait for the third watercolor paper to arrive - if the texture seems OK given what I know now and the weight's OK I'll see how it works and try some of the ideas to deal with the image quality. But worst case I'll just stick with the platinotype paper and be done with it.

So the immediate goals are
  • Go back to the platinotype paper and try to make a "clean copy" of the image above - full sheet, even coating.
  • Experiment a bit with photographing the prints so I can have something to post.
Midterm goals
  • Experiment with third watercolor paper
  • Investigate rise stage options
  • Investigate real contact frame
  • Investigate UV light source so I can print at night and not worry about clouds

2 Comments:

Anonymous funkyjunky said...

Hallo!

Visit this site http://www.alternativephotography.com/index.html

and look up the different processes........

8:27 PM  
Blogger San Francisco Nudes said...

Yep, that's a great resource. They have a book published on cyanotypes which I plugged 6/16 in "Another book plug".

6:21 PM  

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