Tuesday, April 5, 2011

DIY negatives and Cyannotypes!

an easy method of image production on light sensitive materials is to simply lay an object on the paper and expose. This is called a photogram.

Essentially a contact print is the same thing, only much more detailed. A contact print is what we're making when we lay an image (whether positive or negative) directly on the paper, as opposed to making a projection.

Paper negatives are made by oiling or waxing the paper the image is printed on in order to make it much more translucent.  Images can also be made using the paper negatives we created in our pinhole cameras last week. I hope some of you will try to do this.

Maddi said this about her paper negative process :
Maddi Barber's negative

"The first one was a black and withe one, and it had a lot of contrast, so I only opened on photoshop and inverted it.The others were in colour, so I took out the colour and brought more contrast getting more withe and black difference...and invert them.
and that's all!"                                      
Cliche Verre, Unknown Artist
There were a good number of images printed on transparency. With some really great results. There are ways to adjust the "curves" in photoshop to get your image to print exactly how you want. If you are interested in getting more information on making digital negatives let me know, i can try and put you in the right direction.

Another process we didn't get to try but is very cool is the Cliche Verre. This is essentially painting or drawing on a transparent surface... traditional methods include tallow candle smoke, or asphaltum as a resist which was then etched into on the glass to produce interesting images. Sharpies, sumi ink, iron filings could all be very interesting things to experiment with.


this is a very simple process consisting of 2 parts:
part A, ferric ammonium citrate + H2O
part B, potassium ferric cyanide + H2O

after these are mixed, we combine 1:1 of A & B
a piece of A5 paper would use 6 drops A to 6 drops B

the paper is coated with a hake or sponge brush (which has been whetted to prevent wicking of chemistry into the brush) and allowed to dry for about an hour.

afterwards we place our image/object on the paper and expose it to UV light
sunny days will produce more contrasty images while cloudy days might increase tonality

we look for our darkest areas to change from that pale yellow-green to a dark blue-green and then lighted up. We can lift up our image to see the paper "printing out" as it is exposed to light.

it is recommended, as with every process , to make tests.  Everyone coats paper differently, and each negative will yield a different result. Make sure you mark down your technical notes
how many drops of chemistry
date and time of day
weather conditions
time of exposure
all these will help you in the future to make better prints.

develop in water (you may add a splash of vinegar to increase mid tones)
keep in water until highlights no longer appear to be yellow.

for instant gratification, put in waterbath with hydrogen peroxide.
we experemented with some different toners, wine, tea, dektol and laundery detergent.

when finished, wash print for 20 min and lay to dry.
assignment for next week:

bring along all previously made work, negatives etc.
Please make some new negatives as well- go crazy, make some weird and strange things!!!
i want everyone to tear or cut their paper to size for the images they plan to print on. I would like everyone to have enough to use in class, as well as bring some home to make exposures with to bring in for the next week. 
Please write your name and the process on the back before class. 

i would like everyone to email me before next week with a theme for the class book and what process you want to use for your page. As there are 11 of us in the class we will each need to make 12 of the same pages, some processes will be used 2x. I would like to have an extra copy available for Forest to keep...  the dimensions of the page will be 8"x 4" folded in half. If i don't get an email, i'll assign one to you, don't worry it will be fun and i'll help you outside of class to make the pages if needed. 
portal book, cyanotype: Brittonie Fletcher
go to the Ingleby gallery, Anna Atkins (one of the first female photographers) did botany photograms on cyanotype- her work, some of it is there! They also have a wonderful book collection in their basement.

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