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Here is my take.
In Response To: ALPS printer question *PIC* ()

First, there are couple of Yahoo Alps groups - if you are serious about Alps printing, I recommend that you join them. They have about 4500 users each and lots of info it the "Files section", incuding all the available drivers.
https://groups.yahoo.com/neo/groups/Alps/info
https://groups.yahoo.com/neo/groups/alpsdecal/info

Here is my take on your question:

Every once in a while someone asks how to estimate printer usage from the
"bands printed" value obtained from the selftest printout.

I really don't think that this is worth the trouble as just looking at the
number of bands printed already provides a good indication of the printer usage.
I'll explain why it is really meaningless to try to translate that value into
number of pages.

A band is a single head pass over the printed page. Whether the page is 3.5"
wide or 8.5" wide a single head pass will be considered a "band". In standard
color printing (CYMK inks) the head uses 240 head elements, each 0.0016" wide.
That gives a total band width of 0.384". If one was to print a full letter
size (8.5"x11") page, subtracting the top and bottom margins, the printable
area is (11"-0.47"-0.6") 9.93" high. So, 9.93/0.384=25.86 bands. Lets call
it 26 bands.

If the page is fully printed in color then the printer will print 26 bands of
each color on that page. Since there are 4 inks that will be 26X4=104 bands.
If Finish pass is used then that adds another 26 bands printed so we are up to
130.

But is it not quite that simple. If there are areas on the printed page then
the printer will feed the paper through those areas without printing any bands.
So the above calculations are for a page with full ink coverage.

Metallics, Foils and DyeSub inks do not use a full head's width. So the band
counts will be slightly higher per page for those inks.

Many people who print decals do not use full letter sized sheets when printing
decals. So, the above calculation would not be correct in those cases. But does
the page count really matter? I don't think so. I think that just looking at
the "bands printed" value already gives a good indication of how well the
printer is used.

According to the Alps specs, the head has an average life of 250 million
pulses/dots. A dot is a single 0.0016" wide ink spot deposited on paper.
The head is capable of vertically printing 240 of those dots at one time.
But in average printout there are many areas in the printout where dots will
not be printed (the blank areas). There are ways to calculate average values
but that is beyond the scope of this article.

One could also try to calculate a worse case scenario of solid printouts where
all the head elements are printing at all times. But that will also not give an
exact result as the band count does not indicate how wide each printed band was.
Again, the best one could hope for is an average value.

The Alps specs also indicate machine life of 10,000 print cycles. Again, this
is vague. I assume that it means "pages".

So if we follow all the assumptions the life of an Alps printer could be 10,000
pages, each page using up 104 bands. That would be a total of 1,040,000 bands
printed. I don't think that is realistic. I think that the print head will die
before the rest of the printer reaches the end of its mechanical life span.

In my own view a band count of 150,000 or more indicates a well used printer.
But this is just my own opinion. By the same token I would consider a printer
with less than 10,000 bands as a lightly used printer.

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