5.16 PaintJet Parameters
Note that the pixels printed by the PaintJet are square. Thus, a
printout of an image created in a video mode with a 4:3 pixel ratio
(such as 640x480 or 800x600) will come out matching the screen; other
modes (such as 320x200) will come out stretched.
Black and white images, or images using the 8 high resolution PaintJet
colors, come out very nicely. Some images using the full spectrum of
PaintJet colors are very nice, some are disappointing.
When 180 dots per inch is selected (in PRINTER= command), high
resolution 8 color printing is done. When 90 dpi is selected, low
resolution printing using the full 330 dithered color palette is done.
In both cases, Fractint starts by finding the nearest color supported by
the PaintJet for each color in your image. The translation is then
displayed (unless the current display mode is disk video). This display
*should* be a fairly good match to what will be printed - it won't be
perfect most of the time but should give some idea of how the output
will look. At this point you can <Enter> to go ahead and print, <Esc>
to cancel, or <k> to cancel and keep the adjusted colors.
Note that you can use the color map PAINTJET.MAP to create images which
use the 8 high resolution colors available on the PaintJet. Also, two
high-resolution disk video modes are available for creating full page
images.
If you find that the preview image seems very wrong (doesn't match what
actually gets printed) or think that Fractint could be doing a better
job of picking PaintJet colors to match your image's colors, you can try
playing with the following parameter. Fair warning: this is a very
tricky business and you may find it a very frustrating business trying
to get it right.
HALFTONE=r/g/b
(The parameter name is not appropriate - we appropriated a PostScript
parameter for double duty here.)
This separately sets the "gamma" adjustment for each of the red, green,
and blue color components. Think of "gamma" as being like the contrast
adjustment on your screen. Higher gamma values for all three components
results in colors with more contrast being produced on the printer.
Since each color component can have its gamma separately adjusted, you
can change the resulting color mix subtly (or drastically!)
Each gamma value entered has one implied decimal digit.
The default is "halftone=21/19/16", for red 2.1, green 1.9, and blue
1.6. (A note from Pieter Branderhorst: I wrote this stuff to come out
reasonably on my monitor/printer. I'm a bit suspicious of the guns on
my monitor; if the colors seem ridiculously wrong on your system you
might start by trying halftone=17/17/17.)