Jan van Leeuwen photography, cyanotype technique

The cyanotype technique

The making of cyanotypes
Since 1992 I make use of a cyanotype-technique to realize my photographic images. The formula I use is: ferric ammonium citrate III green 20 gr in 100 ml water and 8 gr potassium ferricyanide in 100 ml water.
Only prior to sensitizing I put both solutions together 1:1. I contact-print from paper-negatives, mainly 30x40 cm. This paper is normal Ilford Multigrade PE enlargingpaper from which I strip off the PE-backside and then rub that backside in with paraffin-oil in order to make the negative more transparent.

My UV-lightsources are 3 printcabinets, 2 up to 30x40 cm negatives, 1 up to 40x50 cm negatives. The light inside is, for the first 2, TL-tubes Philips TLD 15W/05 length 44 cm and for the last one TL-tubes Philips TL 20W/05 length 60 cm.

Because these tubes produce UV-B light, all cabinets are tightly closed during exposure. UV-B is dangerous to be exposed to. Exposure-time is from 4 - 5 hours. My cabinets have no fans. As they stand in my darkroom, the least I want is dust whirling around!
In order to avoid overheating and cracking of the 8 mm thick glassplates in the cabinets, I use 2 electrical time-clocks with 15 minutes intervals, one plugged into the mains and showing the total-exposuretime of 8 - 10 hours, the other one, connected to the print-cabinet, plugged into the first one and repeatedly switching 30 minutes on, 30 minutes off, etc. etc.

The papers I use, depending on the kind of images, are:

Hahnemühle
Schoellershammer
Arches Platine
Whatman

Whatman I size with a solution of 1 part water-based PVA adhevise in 4 parts of water, the others I don't size. All waters used are demineralized!
The 30x40 cm paper negatives are made via 9x12 cm interim-positives from 35 mm or 120 rollfilm or 6x9 cm in-camera paper-negatives.

I started to use cyanotype for my self-portraits which I expose during 2 minutes on 6x9 cm incamera papernegatives. The short and steep tonal-scale and darkblue colour of cyanotype enable me to produce images with a very strong impact.