calculating % color

[mshafroth]

I ran apfill on a handout from PowerPoint. The result was:

Page C M Y K
1 2.91 4.6 4.39 0
2 5.26 7.68 13.94 0
3 5.15 6.57 6.51 0
4 5.87 8.44 8.19 0
5 4.6 6.38 6.37 0
6 9.25 10.42 9.01 0
7 3.53 5.13 5.11 0
8 6.26 8.51 9.03 0
9 10.33 10.7 12.18 0
10 6.75 9.73 10.19 0
11 8.03 10.42 9.65 0
12 4.92 7.91 6.76 0
13 8.07 7.66 8.96 0
14 6.04 12.27 15.62 0
15 5.34 6.69 7.24 0
16 5.07 8.87 10.84 0
17 4.81 5.96 5.81 0
18 1.37 1.94 1.91 0
Average 5.75 7.77 8.43 0


When people like HP take about % color coverage

http://www.hp.com/sbso/productivity/col ... _calc.html

What do they mean? How can i get from these results to a % color coverage?

Also i understand that K is black. The handout is mostly black but K always shows 0. Why? Moreover i understand that by using more black in printing you need less CMY (http://en.wikipedia.org/wiki/CMYK). We are using an HP5550. Does the printer or the driver decide how to choose between use of black and CMY?

[support]

Hello

You can use these valuse as % of color coverage for each cartridge.
Here is a good explanation:
http://homeprintingtips.blogspot.com/

If results for K=0 it means your PDF or PS file has not CMYK but RGB color mode. In this case APFill uses GhostScript to convert RGB->CMY. To get results for CMYK you should make CMYK PDF or PS file then it is processed without any conversion.

[mshafroth]

Thanks. After some searching I found that Minolta-QMS Magicolor 6100 driver under XP does allow you to pick convert "Convert Gray Text to Postscript Gray" and "Convert Gray Graphics to Postscript Gray" (under Device Settings). This generates a postscript file (with output to file:) that does use black where it should be used. Without this sort of capability, if I understand things correctly, a color laser uses three times as much toner as it should on the black text and graphics.

Have you considered selling you software to printer manufacturers/Adobe so that the printer could tell the user how much of the toner cartridge is left and so that print shops could charge according to toner use?