Sunday, August 12, 2012

Curves by Intuition (and some experience)

Energized by the good fortune of being able to set up a workshop this summer on a beautiful lake in western Maine, I found the courage to test my understanding of compensation curves used to create digital negatives.  The mountain spring water may be better nourishment for my body (and spirit?) than the city water on the university campus, but the radically different chemistry in the water liked to wash out anything in my images that was less than 50% black.  The standard solution for this problem would be to print a step wedge, analyze the resulting print, and create a correction curve that will stretch the tonal scale to compensate for the odd UV blocking properties of inkjet negatives.  But, this time, I decided to do something less rigorous.  With each image, I manipulated the compensation curve by estimating how much darker/lighter different segments would need to be.  This practice removed many steps in the editing process and forced me to visualize the entire workflow from Photoshop to real printing in the wet darkroom.  After making some big mistakes, I started to get the hang of it, and developed some unique curves for each image.  

For the sake of instruction, I ran an experiment in which I applied some of the curves to images for which they were not originally made.  This made for an interesting comparison that reveals what compensation curves are doing.  Below you will see an image chart.  Each row of pictures corresponds with the curve that was applied (screen capture of the curve at the top of each column).

(click on image to view larger)

The image below was an interesting challenge because most of the visual information exists on the far ends of the tonal scale.  Cyanotype is already a high-contrast process, and this high-contrast image meant that the compensation curve had to extend both sides of the tonal scale and flatten the center.

Friday, August 10, 2012

12 Different Cyanotype Tones Compared

(click on image to make it larger)

1.  Overexposed.  No Bleach.  Very long tannic acid bath.
2.  Brief bleach.  Long tannic acid bath.
3.  Medium bleach (half of cyan color left, half gone).  Long tannic acid bath.
4.  Bleach all cyan color out.  Tannic acid bath.
5.  Long bleach (almost all cyan color gone except in darkest shadows).  Tannic acid and coffee mix for toning bath.
6.  Medium bleach (half of cyan color left, half gone).  Tannic acid and coffee mix for toning bath.
7.  No bleach.  Coffee bath over night (about 7 hours).
8.  Completely bleach all cyan color out.  Coffee bath for about 2 hours.
9.  No Bleach.  Coffee and tannic acid bath for about 3 hours.
10.  Long bleach (almost all cyan color gone except in darkest shadows).  Coffee and tannic acid bath for about 3 hours.
11.  Completely bleach all cyan color out.  Black tea bath for about 3 hours.
12.  No bleach.  No tone.  Native cyan color.


* The bleaching solution used was Borax in water.

* The tannic acid solution is from Bostick & Sullivan.  It is part of their bleaching/toning kit.  It is cyanotype toning solution B.

* The coffee is a dark roast.  I do not remember the brand.  I brewed an entire pot.

*  The tea is Tetley classic black tea. 

*  All the images had a standard exposure time of 10 minutes, with the exception of #1, which had a 12 minute exposure time.

*  The prints were scanned with an Epson Perfection V500 PHOTO scanner.  All color corrections were turned off so things might look a little bit flat.  But, while considering the differences that exist with each person's monitor, web compression, and jpeg compression, I decided to leave the images alone so that, even though they are a little dull, the relative differences would be preserved for comparative analysis.  

Navaho Bridge

cyanotype (toned)

Tuesday, August 07, 2012

basement bathtub photography

who needs a fancy darkroom?

wash bin under faucet, bleaching tray balancing on edge of tub

coffee toner on left, tea + tannic acid toner on right

Monday, August 06, 2012

making cyanotype cards

to say thank you to all the people who supported the Grand Canyon Gravure project, and helped it start the second phase of development.

Thursday, August 02, 2012

A Collision: Media and Environmentalism

 This is an interesting concept. I'm not sure if they have a deeper agenda or are relying only on the juxtaposition of a billboard and nature (much of that probably depends on the content of the billboard itself).  In trying to decide whether or not to support this project, i went through many scenarios in my own head about how I would do it myself. It brought up major questions that orbited around the intent of the project. It could be overtly didactic, pushing an agenda of either environmental conservation or technical progress at all cost. It could be simple juxtaposition without the slightest hint of artist(s) intent. Irony would be easy (and probably gain much immediate attention).

 In the end, I decided that I wanted to see what these two artists would do with the idea, so decided to back the project.