Estimating Toner Coverage

  • Thread starter Thread starter c.jopp
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c.jopp

I'm thinking of buying a colour laser printer to produce short runs of
leaflets, pamphlets and such. Most manufacturers seem to quote a cost per
page in the order of 5 or 6p based on a 5% toner coverage per page. I think
this relates to a full page of text but I'm not sure. It seems to me I
would need to quote per job rather than advertise a fixed price per page as
the cost could vary so much. Is there any way of estimating/calculating what
the toner caverage for a particular page might be. Failing that what would
say a page of 50% text plus 50% colour photo be. How about a full page
colour photo?

Any help or advice much appreciated.

John
 
I have seen it done but you have to scan in the actual page you are going to
print and then run some software that analyzes the page. It is not a simple
thing to do unless you are dealing with mono.
 
Lukasz Spychalski said:
I did it in mono.
Full A4 page inkjet printed with 65 lines of 80 chars black Courier 10 cpi
was scanned in 300 dpi bi-level, then black bits were counted.

It gave me AFAIR about 20% of coverage. There is a little error (less than 1
%) as no bmp header stripping was done.

If anybody is interested in the software (very, very basic - ugly DOS ;) - I
probably lost the sources) - I can put it on www.

Best regards,
Lukasz
Click to expand...

20% sounded a bit high to me so I did a little test in Photoshop. I scanned
in a section of solid text as a black & white image, converted it to
greyscale and did two gaussian blurs to get a relatively even grey colour
and then checked the values with the eyedropper tool. I got values ranging
from 10% to 30% with 20% being about the average so it looks like you were
right. Taking it further I scanned in an average sort of colour photo and
did the blurs again and got readings probably averaging about 50%. Less in
the light areas and more in the dark areas. Black was less than the cmy
values at about very roughly 10% on average.

So can I assume that if a printer is quoted as 5p per page for 5% coverage
it would cost 50p for 50% coverage ( a "typical" colour photo). If so this
is much more than I thought. Or is it not that simple?

John
 
On Tue, 15 Jul 2003 10:08:11 GMT, Wayne Ware wrote:

=> Most manufacturers seem to quote a cost per
=>>page in the order of 5 or 6p based on a 5% toner coverage per page. I think
=>>this relates to a full page of text but I'm not sure.

You're right, 5% is a page of text, with 1 inch margins all round, and no
iamges at all.

Since a colour laser uses four (or more) rioner cartridges, and each costs
about the same, the 5 or 6p per page is reasonable, IF your are printing
coloured text only, no images.

However, a full page colour print of a photo will have considerably more
than 5% coverage -- 50% and up for each colour for a typical image. Text and
image mixed will use a good deal less colour, of course.

I've had text & colour mixed quoted to me at 50 cents a page _minimum_, by a
reputable dealer, but since I haven't made the plunge yet, I can't tell you
how accurate that quote is. I've calculate black text (5% coverage) at 1 to 3
cents/page, depending on printer model, and jusing the mfr's page count
ratings for the cartridges.

HTH&GL.
 
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