Meant to reply the other week. I converted a flatbed scanner to a UV exposure box in Feb for my girlfriend to use, as she had experimented with the cyanotype process in the past but hadn't done as much as she wanted to due to the lack of decent sun in the UK. I saw some examples of UV exposure units and Rich off here sent me his old scanner to tear apart. Added a screen and used the existing buttons to control time and brightness. Arduino in the back doing the clevers.
This was my first (or maybe second) attempt. I printed a photo of mine on to tracing paper then exposed on some chemical covered paper.
Since done more, here are some examples. I tend to do photos, girlfriend enjoys exposing actual items (yj) (flowers, leaves, feathers etc). These were all 15 minute exposures using negatives printed on transparencies.
This was an attempt to get as much feather detail as possible. Total unknown until you try various lengths of time. Tried 15 mins, 30 mins and 45 mins. This was the 45 min attempt. I think the 15 min attempt was mostly white where the feather is - meaning not exposed enough at all since the feather blocks the UV getting to the paper.
The 3 photos in the middle were exposed using a small 6x4 sized unit I made for myself
EDITED: 6 May 2020 09:13 by ANT_THOMAS