Technique -Laser Printer Masters

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Positives -Film, Laser or Otherwise

With the Rubylith technique a master image was cut from material that allowed us to control what parts of the emulsion were exposed and washed out versus what areas were to remain.  Rubylith offers fast exposure times at only ninety seconds in the exposure machine. But it is also labor intensive to create the masters.  Frequently, as part of the creative process, images are first made on a computer that are then used as a tracing guide.  This works well if a handcrafted quality is desired. Often though, the computer image will be exactly what is wanted.  By using layers in a graphic program, a master image can be created for each screen.  To get the best result, three things are required.. First, that the image be printed on a laser printer- ink jet printers don't print opaque enough images for this technique although they work well when printing to transparent film. Second, that the graphics program can make use of layers. Finally, that you have access to a laser printer with capacity to print your piece- don't forget about what the nearest copy center has!  To start, create a digital image with each feature as it's own layer.  At the creative stage the work can be in color, keeping in mind that each new color will require a new screen be burned for it.  Also bear in mind that a digital layer, at this stage, does not represent a burned screen.  There can never be too many digital layers, with some digital artists using hundreds of digital layers in the creation of their art!  As the process continues  the digital layers that are to be printed in red, for example,  will be grouped together and merged.  Then merge the next group of similar colors until each group of color is on the same digital layer.  At this stage there should be one layer for each intended screen.  The final step in the process is to convert the color of each image / screen into pure black and print it.





The above example has been boiled down to three layers. Each layer represents one screen, black, red, and metallic copper.  All the layers are shown but each can be printed individually.  The exposure unit works by exposing or not exposing areas of emulsion.  It's binary in nature, off or on.  It will not work with in between values.  An image printed on the laser printer in green will be read at exposure time as an intermediate value - gray and will produce an unexpected result!  While the exposure times for Rubylith are very fast.  The exposure time for a laser master is a lot slower.  Set the exposure table for five minutes and burn the screen!

My Take on Software-

There is a lot of talk about what is "needed" to use computer graphics in screen printing.  Simply use what is available.  At this level, vector capable packages such as Adobe Illustrator or Indesign will get you  the same result as the freely available Inkscape.  On the bitmap side of graphics software, Photoshop is widely used but perfectly acceptable results can be had using Paint Dot Net or The Gimp, both free for Apple and Windows systems.  In fact, the image above is shown being edited in Photoshop Elements, a free application that arrived with my scanner, but I also created parts of Roosters Gonna Roost using Paint Dot Net because it was what was available where I was at the time.  For advanced work, such as process color printing, professional, packages do have their place but far too much is made of what is "needed" to start out. Go with what you have access to and make prints!


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