This is a how to, what with, what on and how much to use article and though it’s aimed at Cyanotype printers it can be used, with patience with other processes needing coating.
I print Cyanotypes for two reasons, it’s a fairly safe thing to do in the average home and it suits my subject matter. Its advantage from a coating point of view is the colour of the mixed sensitiser, a nice visible yellow and the fact that it can be done under quite a bright tungsten lamp. I use a 100 Watt lamp in a ceiling fixture and have never had any fogging problems. I guess that’s a bit tongue in cheek though, it’s such an insensitive process that you would have to hold it half an inch away for half an hour to make any impression at all.
The usual advice is to go and buy some paper and coat it, well I’ll take it a little further than that and start with the paper. Firstly it’s off to the local newspaper shop or stationery place to buy some cheap cartridge paper, about 120 gsm if you can get it. This will be adequate for making ‘proof prints’ against which you can judge the exposure for the ‘really good print’. Really good prints can be done on Canson ‘Montval’ watercolour paper, and if ever a paper was suited to a process it wasn’t intended for then this is it, it’s available from most arty shops and can be bought on the web by mail order.
Obtaining a brush or two is the next thing, visit your local hardware or ironmongers shop and find some pastry brushes, a flat one and a round one, bristle ones if you can get them but the nylon ones are not so good. Wooden ones are recommended but I’ve used a flat one with a metal ferrule for years and never noticed any stains from dissolved metal even after 7 or 8 years. The flat one can be used to cover the whole of a sheet of paper and the round one for some wild edge effects. Be prepared for the liquid to flick around a bit with these rather coarse brushes, wear an apron and if you feel the need gloves and some goggles. The splashes dry to a nice visible blue and are easily removed with household washing soda dissolved in water.
If you want controlled coating then the Japanese ‘Hake’ brush is the best thing ever invented, it gives up almost as much fluid as it takes in and the coat is beautifully even. All the brushes should be rinsed in cold water only and not for too long.
To cover an A4 sheet you will need about 5 ml of the sensitiser, I use one of those ink cartridge refill syringes to suck up the exact amount of each of the fluids and squirt it carefully into an old saucer.
Take your chosen brush and dip it in the fluid, use it to mix it thoroughly and then draw the brush over the side of the saucer to release some of the liquid. Begin the coating with the brush near to you and within the area you want to cover, make the first stroke away from you and drawing the brush up the paper. Repeat this until you have roughly covered the width and length you want. Go over it again from the top and then from side to side. Do not let the paper ‘dry’ and you will see what I mean by that the first time you do it. If you want jagged edge effects be careful not to put too much on and if you are coating the whole of a sheet make sure the coat is as even as you can get it. About two minutes is the absolute maximum with less than one minute being the ideal time to aim for. Having finished put the paper away somewhere dark for an hour or so. I use an old chest of drawers with black velvet stuck to the rim to keep out any light, my darkroom not being as light tight as it used to be.
After trying this a few times you might want to use some different techniques, you can make a negative with a wide black border, which will give a white surround to your print. The wild edges are quite nice and good fun to do, but a bit hit and miss.
Because it’s possible to see the liquid as you coat the paper the coating can be quite precise. Draw a rectangle half an inch larger than the image area lightly with a pencil and coat the paper so that you just cover this penciled rectangle, this gives a nice border to the print that’s not too even and looks very good indeed. Try drawing another rectangle that is just the size of the image and coat the paper within that area. The reason for doing this is so that the straight edges of the image/negative edge will not be visible on the paper.
You do have to line up the negative and the paper quite precisely to do both of the above. Great care is needed when assembling the contact frame, check to see if everything is in register before exposure.
Trying different coating techniques is great fun and having chosen one to use, to watch a really beautiful print appear is a great joy.
The three pictures that accompany this article are, one using the ‘wild’ edge with a round pastry brush, another within a pencil boundary and coated with a Hake brush, and the third one the brushes, from the top down, flat pastry brush, round pastry brush, (new) and the much used Hake. The paper I used to make the two prints was Winsor & Newton’s new creamy 220 gsm heavyweight smooth surface cartridge paper, it produces a lovely deep blue tone and recovers well from being immersed in water.