Making a relief plate requires the use of a negative. The basic scenario is this: a negative allows a lot of light through the clear areas and no UV light through the dark areas. The dark areas of the plate do not harden and the light areas harden completely. What this requires is a negative that has very dense black ink intended to block light.
Fortunately for those using Epson printers for making relief negatives, there exists a wonderful little RIP (Raster Image Processor) called QuadToneRIP that gives complete control over how ink is deposited on the negative. The usefulness of this amount of control lies in the ability to put lots of ink where it is needed and none where it is not needed. Relief negatives have just such a requirement: block lots of light in the areas that are to remain unhardened and block none where they are to be hardened. It is completely an on/off situation.
There are only a few things necessary to use QuadToneRIP. The first is that you must use an Epson inkjet printer. This RIP works only with the Epson brand of printers. The second is that you must install the program on your computer. The QuadToneRIP website is found here . Note that this software is shareware, and Roy Harrington, the creator of the software asks that you pay $50 if you find the software useful and intend to use it. Keep your karmic balance and send him $50 if you intend to use the software. He has been a generous and responsive developer over the years and it seems the right thing to do.
Download the appropriate software for your computing system (i.e. either Windows or Mac) and follow the installation instructions. One note: you will need to have the underlying Epson driver software installed and the printer must powered on and hooked to your computer through either a USB cable or via WiFi for the installation procedure to work properly. I will not get into the details of the installation process here, but if problems arise, there is a Yahoo forum group that is very active and it is likely you will find someone in that group who will be able to help you out.
There are only a few things necessary to use QuadToneRIP. The first is that you must use an Epson inkjet printer. This RIP works only with the Epson brand of printers. The second is that you must install the program on your computer. The QuadToneRIP website is found here . Note that this software is shareware, and Roy Harrington, the creator of the software asks that you pay $50 if you find the software useful and intend to use it. Keep your karmic balance and send him $50 if you intend to use the software. He has been a generous and responsive developer over the years and it seems the right thing to do.
Download the appropriate software for your computing system (i.e. either Windows or Mac) and follow the installation instructions. One note: you will need to have the underlying Epson driver software installed and the printer must powered on and hooked to your computer through either a USB cable or via WiFi for the installation procedure to work properly. I will not get into the details of the installation process here, but if problems arise, there is a Yahoo forum group that is very active and it is likely you will find someone in that group who will be able to help you out.
So let's get to the nuts and bolts of this. The way that QuadToneRIP (hereafter referred to as QTR to save some typing) works is that ink profiles are installed using the installation script for the particular printer you use. Again, we will not get into the weeds on installing the profiles, but the short version is that a text file needs to be dragged into the installation folder and the installation script is activated by double clicking it in the folder . Please note that these instructions are particular to the MacOS version. The Windows version is slightly different, but involves selecting the file in a GUI instead of dragging and dropping.
The ink profile we will use will take advantage of the control over the amount of ink the printer lays down on the overhead transparency film used to make the negative (I recommend Pictorico Premium OHP, InkPress or Fixxons).
Here is what the text file has in it:
PRINTER=QuadR3000
CURVE_NAME=SolidBlack
GRAPH_CURVE=YES
N_OF_INKS=8
DEFAULT_INK_LIMIT=100
BOOST_K=100
LIMIT_K=70
LIMIT_C=
LIMIT_M=
LIMIT_Y=30
LIMIT_LC=
LIMIT_LM=
LIMIT_LK=10
LIMIT_LLK=10
N_OF_GRAY_PARTS=1
GRAY_INK_1=K
GRAY_VAL_1=100
GRAY_HIGHLIGHT=10
GRAY_SHADOW=10
GRAY_OVERLAP=
GRAY_GAMMA=10
GRAY_CURVE="0;0 99;0 100;100"
N_OF_TONER_PARTS=0
TONER_HIGHLIGHT=10
TONER_SHADOW=10
TONER_GAMMA=1
TONER_CURVE=
N_OF_TONER_2_PARTS=0
TONER_2_HIGHLIGHT=10
TONER_2_SHADOW=10
TONER_2_GAMMA=1
TONER_2_CURVE=
N_OF_UNUSED=6
UNUSED_INK_1=C
UNUSED_INK_2=M
UNUSED_INK_3=LC
UNUSED_INK_4=LM
UNUSED_INK_5=LK
UNUSED_INK_6=LLK
COPY_CURVE_Y=K Copy the text, edit the printer name and save it as a text file with a name like SolidBlack.qidf and move it into your QTR installation folder for your printer. Install it and then test it out. If ink pools on the transparency film, edit the file to reduce the black boost percentage somewhat.
The key things to notice here are that we are using an extremely high gamma setting of 10, and using black boost to make the maximum ink load of 100%, evenly split between 70% black ink and 30% yellow ink. Then we use a gray curve that knocks all the printing values under 99% to 0% ink on the film.
On my R3000 printer, I am able to get UV densities that measure 4.04, which is effectively bulletproof to light.