DEVELOPING DIGITAL TUSCHE WASHES FOR PHOTOPLATE LITHOGRAPHY

Undoubtedly there is something quite appealing about the polished smooth surface of freshly grained limestone, the colour of rain, awaiting the touch of crayon and the play of grease and water. For me too there is a fascination about how grease interacts with the calcium carbonate and there is, I have to confess a near obsessive compulsion to watch tusche wash drying on the surface of the stone - to see the black pigment settling out into reticulated web-like structures of sheer intricate beauty.

It may seem ironic then that a stone-man such as myself would be remotely interested in the virtual world of pixilation, digitisation and computer generated images. Since 2008 however I have become increasingly interested incorporating digital methods of working with traditional techniques of stone and plate lithography. Updating earlier research completed in 1996 for The Tamarind Institute (Developing Customised Wash Palettes and Brush Tools) - current trials using a Wacom Intuos 4 Graphics Tablet, Adobe Photoshop CS4 and Corel Painter 12 has proved innovative for the development of digital tusche wash.

Unique to Corel Painter 12 are the system of Nozzle Files, Image Hose and Cloning Brushes that enable an ever expanding library of washes - originating as drawn, printed tusche and crayon, scanned, manipulated and saved as files of customised palettes; to be used as the basis for almost limitless series of variant brushes. Fragments of tusche wash stored within Nozzle Files are accessed by Image Hose as a stylus is dawn over a pressure-sensitive graphics tablet, causing reticulation to spread across the screen - canvas in a sophisticated and subtle manner that is as authentic as tusche wash on stone.

That Nozzle Files can be constructed using as many different tusche elements as you want and can be ranked according to scale, tone, type, space and colour; and given that customisation of brushes can control size, shape, angle, tilt, pressure, spread, spacing, transparency and how layers are built up and interact with each other - is indicative of how sophisticated digital imaging has become in the last fifteen years.

Use of Image Hose and Cloning Brushes combined with more rudimentary cut-and-paste enables layers of drawing to be developed that can subsequently be outputted for printing from photoplate as colour runs in any given print. Commonly these colour runs are printed in series and are then overprinted with a key image from stone drawn using conventional techniques. Further manipulation using digital tools serves to provide a limitless range of drawing - which when juxtaposed with conventional lithographic crayon and wash create interesting and exciting dynamics in the final images. Customised washes can easily be exaggerated in scale, inverted, resized, cut and pasted to print with whatever design or composition is being developed.

That colour runs can be developed on the computer enables for rapid working since layers transferred to Photoshop can easily be saved and printed out either on to acetate or ideally, on to film using an Image-Setter for subsequent exposure on to positive working photoplates. Furthermore the image can be colour-proofed digitally using Photoshop - thus allowing for decisions on colour, blends and colour mixing to be made more easily in the studio.

Paul Croft presented results of his research at IMPACT 7 - Intersections & Counterpoints - International Multi-Disciplinary Printmaking Conference - Monash University, Melbourne, Australia. September 27-30 2011 See: http://impact7.org.au/index.html This was an extract from an article published in Printmaking Today, Volume 21 Number 1 Spring 2012. If you are  interested in learning more about Digital Tusche washes please let me know by email at: puc@aber.ac.uk

Between Spaces II (Test Print B)  100mm x 250mm 2011

Image developed using a combination of cut and paste tusches, Image Hose and Cloning Brushes. The image - outputted onto textured film was exposed to photoplate and printed in conventional manner

Between Spaces V (Test Print E)  100mm x 250mm 2011

Image developed using a combination of cut and paste tusches, Image Hose and Cloning Brushes. The image - outputted onto textured film was exposed to photoplate and printed in conventional manner