Monday, May 9, 2011

07. Cyanotype

Introduction:
cyanotype: a photographic process which produces a cyan blue image.  The cyanotype was an inexpensive and easy way to reproduce work efficiently.  The process was used in the 20th century by engineers for this reason.  A negative image is produced by the process.  Sir John Herschel invented the cyanotype process in 1842.  He envisioned the cyanotype to be used for reproducing notes and diagrams.  This was how the process was used until Anna Atkins began creating cyanotypes for aesthetic reasons.  She documented botanical subjects and made many books.  Anna Atkins is considered to be one of the first female photographers for this reason.
  


Anna Atkins: born in 1799, she was an English botanist and photographer.  She was the first to make what can be considered a "photo book." 


Process:
1. First we chose and cut down our paper (100% rag).
2. We then coated our paper with the cyanotype solution.
3. Next, we put our paper and negatives in the printing frame, negative facing outward.
4. Our paper was then exposed for about fifteen minutes.
5.  The print was then just washed in water for a half hour.


Cyanotype Recipe:
Solution A:      25 g Ferric ammonium citrate (green)
                        100 ml. water
Solution B:      10 g Potassium ferricyanide

                        100 ml. water
 Mix equal parts of both solutions to form the final cyanotype solution.

**The generic cyanotype recipe of today is not much different than the one created by Herschel.


Toner Recipes:
Weak Ammonia solution:   5% ammonia
Strong Ammonia solution: 250ml ammonia
                                           1qt. water


1) tea: tea and water
2) reverse: tea then strong ammonia
3) redevelopment: weak ammonia, rinse in water, tea


Experience:
I only made one cyanotype in lab and it did not turn out the way I wanted.  I started off on the wrong foot because I had a thin negative.  The print is very dark and over exposed by about two or three minutes.  After a wash in the water some pigment came off but still there was little to no detail in the shadows.  Another reason for the print being so dark is that I could have put too heavy of a coating on the paper.  After my image was washed and dried I tried three different toners on my image.  The results are more noticeable in person but overall I think the image is just too dark to see a huge difference.




 Negative used for cyanotype

Summary:
To produce better results I need a better negative.  I also need to experiment with exposure time more to make sure I do not over expose my image.  I still want to play around with toning too.  It was hard to really see a whole lot of difference between the three images.

Links:
http://en.wikipedia.org/wiki/Anna_Atkins
http://en.wikipedia.org/wiki/Cyanotype
http://www.alternativephotography.com/wp/processes/cyanotype/cyanotype-classic-process
http://www.mikeware.demon.co.uk/cyano.html

Images:

1 comment:

  1. last image belongs to Emil Schildt.yuu should credit him.

    ReplyDelete