Re: Banding in grayscale

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Olaf Ringdahl wrote:

>On a photo EX, when I Print a grayscale image, using black ink only, I =
>get a very faint horizontal banding which I do not get when printing the =
>same image in RGB, using all six inks. (Nozzles and alignment are OK.)
>The banding is visible only under a magnifying glass but it is there and =
>I would like to be rid of it.=20
>Any suggestions?

I think you're up against one of the characteristics of the Epson error
diffusion algorithms. They appear to be designed to work optimally when
all four (or six) colors are utilized, but tend to band when only black
ink is used. My SC900 produces lovely grainless black-ink-only images when
the subject matter is sufficiently varied -- but smooth areas, like sand
or deeply shaded snow falling in what Adams might have identified as zones
3 or 4, show troublesome banding. It looks as though the printer can't
decide whether to print a 15% gray or a 25% gray, so it prints one shade
for a few millimeters then shifts to the other, then back to 15% and so on.

When I complained about this to Epson, they replied with essentially what
I've said above. That's just the way the Epson ball bounces.

dave f.___________

Dave Fanger (dfanger@world.std.com)
-
Turn off HTML mail features. Keep quoted material short. Use accurate
subject lines. http://www.leben.com/lists for list instructions.


[Index of Archives]     [Yosemite News]     [Yosemite Photos]     [Scanners]     [Gimp]     [Gimp Users]
  Powered by Linux