Digital BW, The Print

> From: Tom Husband [mailto:thusband@...]
>
> When printing a 16 bit file does the printer convert it to 8 bit?
> I've been trying to get the author of Qimage to allow processing of
> 16 bit grayscale files.  Qimage has a feature called "print to file"
> where you don't send the file to the printer but to another
> location.  It's a great feature but it takes a grayscale 16 bit file
> and converts it to 8 bit RGB.  Anyway, Mike Chaney has responded with
> the following, "I'd also have to question why you'd want to print 16
> bits/channel when printing to file because printers cannot accept
> anything but 8 bit data (even when using a RIP). As far as I know,
> and unless things have changed recently, all printers (the hardware
> itself) are based on 8 bits/channel even when dealing with grayscale."
>
> I was thinking that it might happen when using the Roark curves and
> the Epson drivers but how about using QTR?

What goes across the cable to the printer (at least for Epson) is dots, not
8-bit or 16-bit data. Standard printer drivers convert the image to dot
patterns, but only accept 8-bit data. Alternative software, like a RIP,
could in theory use all 16 bits, but I couldn't tell you if QTR does. For
B&W, it's possible that an extra bit or two might be useful on some media,
but it's doubtful that you'd see the difference for color.

--

Ciao,               Paul D. DeRocco
Paul                mailto:pderocco@...