Topic: Cyanotype - help needed

[Janet_P]

Does anyone have any experience with cyanotypes? What colour should the sensitizer be when it coats the paper? My impression was that it would be blue but I get yellowy green with blue at the edges (I'm brushing it on).
When I expose it to UV light nothing happens to it at all.
Where have I gone wrong?

Anyone?

thanks
Janet

[Tammy]

Hi Janet,

I have a little bit os experience with cyanotype.  I use a kit which  comes in 2 parts and I mix them equally and brush it on.  Not sure if you have a kit like this, or if you might have made your own.

Anyway, the solution is pale yellow to yellow green on the paper when dry, and when it is exposing in the sunlight it turns a steely grey color.  I almost get an image reversal, but it's very muted in coloring.

Once I rinse under water, the cyanotype becomes blue.  It's the water development where the color is very dramatic.

Hope this helps! 

[eyecaramba]

I am with Tammy on this.  Cyanotypes do look yellow green limonish before exposure unless you leave them out for a while unexposed and then they trend towards that steely color even though they can still be usable for a while. 

Anyway, no worries so far it seems.  Cyanotypes are so easy to do.  They are quite a bit harder to do well but it isn't too hard to get into the ballpark.  I am on a septic system now and have been getting a bit further into the blueprinting myself, thinking this is a better waste stream - and I do try reclaim my fixer and try to find alternative dumps for my stop and fix and toners... Cyanotypes are more a more innocent pollutant.  Or so they say.

[Janet_P]

The sensitizer I'm using is a single solution from Fotospeed

http://www.fotospeed.com/Product.asp?Prd=08511

It sounds like it's coating OK and I've noticed that the paper I coated a couple of days ago has turned that Steely gray you mention. Perhaps I'm not exposing it for long enough? I have a UV light set up and I've left paper under for a variety of times, from 1 minute up to 5 minutes. Is that too short?

Thanks

Janet

[rdbkorn]

Hi Janet. I 've done quite a few cyanotypes in the past couple of years. I generally use sunlight for exposure. In the summer, when the UV index is high exposures in the sun for me range from 5 to 15 minutes depending upon the density of the negative and the time of day. In the fall/winter, times would be much longer, given our relatively northern latitude (I live in Canada). I have tried a home-made exposure unit with two fluorescent UV bulbs, and get only a weak exposure with 20 minutes, so I suspect you just aren't exposing your cyanotypes long enough. It might be good to try a photogram (flower, leaf or whatever) first to get a baseline for exposure time, and then try that as a starting point for negatives.

[Marcello]

Hi Janet,
did you use a glass slide to keep the negative flat on paper?
Glass is not transparent to UV light.
Just a thought.
Ciao Marcello

[rdbkorn]

Certainly glass will absorb some UV light and you will require a longer exposure, but people have used contact printing frames (which have glass) to successfully print cyanotypes all the time.  Difficult (impossible?) to keep the negative flat on the paper without using a glass frame.

[Francois]

Just make sure you don't use acrylic in your contact frame since it blocks 98% of UV rays. That's why it's so good in picture frames...

[MarkBurley]

Hi Janet,

I recently spent a day with a guy that produces amazing cyanotypes, amongst other things...

I think he would probably be only to pleased to offer some advice if asked...

His name is David Chow - see Davec101 on APUG. He sells his images on a regular basis and regularly features in mags. He was talking about providing workshops etc.

He has a calibrated system that seems to be spot on. I don't think he would mind being asked... but I guess I will have some apologies to make if he does... see the following address for more info...

David Chow photographic processes blog :
http://altphotoprocess.blogspot.com

[Janet_P]

Thanks for all the brilliant advice everyone. The photogram suggestion was genius as it helped to get an idea of the times I was working towards. It seems that I needed to leave it exposing for waaaaayyyy longer (40 minutes instead of 5). I also think the neg isn't contrasty or large enough to get the detail I was hoping for. My next step is to work how to produce a digital negative.
I will be checking out David Chow's blogspot and the book that I remember Ed reviewing in B&W mag on creating digital negs.
It does mean that I have failed to produce an image for the Poetry Day collaboration  but I think I will persevere...