| The Science
Behind Page Counts, Cartridge Yields and
The 5% Rule!
Everyone
wants to make the right decisions when buying printing supplies.
Reliability, print quality, print speed and ease of use typically
are the most important considerations, but comparing costs is also
very important. You want products that deliver on their promise!
What Is Printer Yield?
Customers are becoming increasingly
aware of the cost of owning and operating their printers and
multifunction products (MFPs). The cost of consumable supplies such
as toner cartridges or solid ink sticks is a major component of the
Total Cost of Ownership (TCO) for a printer or MFP. The per-page
cost of printing is driving many printer and MFP purchase decisions
today, as these costs can be combined with print volume and print
coverage assumptions to give companies a reasonable estimate of the
monthly and annual TCO for a specific printer or MFP.
In the past, printer and MFP original
equipment manufacturers (OEMs) used different, proprietary methods
for testing and reporting consumable yields. This made factual and
accurate comparisons of products from differing manufacturers
impossible. Reporting was traditionally done using “5% area
coverage,” but that did not guarantee comparable results because
many other testing variables affect the stated yield, including:
-
Page size and margin settings
-
Image types used to create 5% area
coverage
-
Number of cartridges used during
testing process
-
Number of printers/MFPs used during
testing process
-
Environmental testing conditions
(humidity, temperature, and so on)
-
Lack of stated confidence level for
published consumable yield
Any variation in these factors during
the testing process can cause significant differences in reported
yields. The development of an industry standard method for testing
and reporting consumables yields has helped eliminate these
inconsistencies, and gives customers the reliable information they
need to make their technology buying decisions. Thus, almost
all manufacturers now support industry standards such as those set
by the International Organization for Standardization (ISO).
The
International Standards
The ISO and IEC have adopted a
standard for black-and-white devices – ISO/IEC 19752 – which
is described as a “method for the determination of toner cartridge
yield for monochromatic electrophotographic printers and
multifunction devices that contain printer components.”
Black-and-white printers and MFPs reporting
toner yields under ISO/IEC
19752 use the following explanation: Toner Cartridge Yield: Average
XX,XXX standard pages (declared yield in accordance with ISO/IEC
19752. Yield will vary based on image, area coverage and print
mode).
ISO/IEC 19798 is a similar
standard that has been adopted for
color laser devices. ISO/IEC
19798 is described as “a method
for the determination of toner cartridge yield for color printers
and multifunction devices that contain printer components.”
Reporting format is as follows: Average Continuous CMYK Yield:
XX,XXX pages, or Average Continuous CMY Yield: XX,XXX pages and
Average Continuous Black Yield: XX,XXX pages (if the black Yield is
different than color - such as where a printer has a larger capacity
black cartridge).
ISO/IEC 24711 is another
standard that has been adopted for inkjet and solid ink devices.
ISO/IEC 24711 is described as “a method for determination of ink
cartridge yield for color inkjet printer and multifunction devices
that contain printer components.” Reporting format is similar to
ISO/IEC 19798 shown above. Different implementations of color tables
and color balance optimization among manufacturers can lead to yield
variations between color cartridges, even if they have the same
toner weight. To account for this, ISO supports a second reporting
method called “composite yield,” allowing a single average reporting
yield for Cyan, Magenta and Yellow toner cartridges. Black is
reported separately as an individual yield. Average Continuous
Composite CMY Yield: XX,XXX pages. Average Black Continuous Yield:
XX,XXX pages.
ISO/IEC 19752, ISO/IEC CD 19798, and
IS0/IEC 24711 specify the use of a standard test page for
black-and-white and multiple test pages for color products, explicit
testing procedures, statistical sampling, environmental controls and
well defined cartridge end-of-life status.
ISO Standard
Methods
Because of ISO's explicit test
procedures, the ISO standards are the only standardized rigorous
method for determining toner & ink cartridge yield for laser, color,
and ink jet printers. Some of their key features are:
-
Using
A Standard test document:
Use of a standard page printed with printer default settings.
This ensures that settings remain consistent across different tests,
independent of platform or paper size. The document uses 5% coverage
as its basis for comparison. (see photo of document at right)
-
Number of cartridges tested:
Nine of each cartridge are tested, allowing reliable estimates
of lowest predicted yield with 95% confidence.
-
Source for cartridges:
Cartridges and printers are purchased on the open market from
three different sources. This ensures the cartridges tested are
representative of those available to customers and ensures lot
variation.
-
Clear, objective, end-of-life criterion:
Determines cartridge yield through measurements that establish
an end-of-life criterion based on usable pages and that reflect the
manufacturers' recommendations on how cartridges should be handled
as they approach their end of life (for example, how many times they
should be shaken).
-
Number of printers:
Cartridges are tested on three different printers (three
cartridges on each printer) to avoid bias due to printer
variability.
-
Controlled environment:
Printing environment is controlled and consistent because
temperature and humidity variations affect cartridge yield.
-
Objectivity:
Because of worldwide and industry-wide participation, this
reflects objectivity in developing a reliable and rigorous standard.
The ISO/IEC standards allow for
objective comparisons of stated toner or ink yields for different
printers or MFPs, regardless
of the manufacturer. Many customers use consumable yield information
to estimate the toner life they can expect to
experience with their particular use and printer, and the
manufacturer's adherence to these ISO/IEC standards enables this
comparison. But, it is important to note that the yield is a
comparative statistic, and not a real world prediction of the final
results. The number of pages that any user will get for their own
printer will depend on a variety of factors, with page coverage
(square inches of printing, density, and quality settings) having
the highest impact. Research has shown that the industry average
black-and-white page coverage is between 4% and 5%. There is an
inverse relationship between page coverage and toner/ink yield — the
lower the page coverage, the more pages
the toner/ink will print. Conversely, higher coverage pages result
in fewer printed pages.
Cartridge yield -
Things To Consider
As we indicated in this Guide, many factors affect cartridge yield.
These include:
-
Coverage of the printed document - how much toner is printed on the
page. Values are usually based on 5% (page of text) coverage.
-
Temperature and humidity.
-
Age Of Cartridge.
-
Toner "Hopper" or Ink Reservoir Design.
-
Drum or Print Head Design.
-
Storage prior to use.
-
End Of Life Actions (such as shaking).
Q&A On Printer
Yield
Q:
Can I get the published yield for my specific printer?
A:
Unfortunately No. The standards just ensure that the stated printed
page yields of different printers are comparable, not what you will
actually get (unless you only print thousands of the ISO test
page!). Also, the yield page number is not a guaranty that
users will get
the declared yields in their own printer (as page coverage has the
highest impact on actual yields). User applications running at
approximately 5% page coverage under normal office operating
conditions can expect on average to experience yields that are
fairly close to the ISO declared yields. Home users though may
not get anything close, since home printing tends to be much more
high coverage graphics, which reduces yields dramatically.
Q: What
are the factors that will impact the user's yields the most?
A: The
most important factor affecting yield is page coverage. It is
not unusual for office or home usage to run above or below that 5%
average (for example, if you print a webpage with the Print
Background Graphics option on, you could be printing 80%+ coverage).
In general, pages with significant dark, shaded, or colored areas
(logos or pictures) or a large amount of fine print will generate
area coverage much higher than 5%. Other factors that
can reduce cartridge yield include: higher temperature or higher
humidity levels where the printer operates (in laser printers, high
humidity can cause clinging or clumping of the toner, and in inkjet
can cause evaporation or clogging of the print jets), and using a
higher print resolution setting (which causes more dots to be
printer per inch resulting in higher density). Color coverage
varies by product class, but is generally much higher than
black-and-white products. Letter/A4-size color printers and MFPs can
have average page coverages in the 7 to 15% range (depending on the
application and mix between color and black-and-white documents).
Tabloid/A3-size color printers and MFPs tend to drive higher
color page coverages in the range of 10 to 30% in office
environments. In graphic arts environments, average color page
coverages can increase to the 40 to 60% range. In the home, coverage
can be even higher since home users tend to be less aware of options
and use best quality regardless of need.
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Tags:
Inkjet Printers,
Laser Printers,
Color Printers,
Inkjet cartridges,
toner cartridges
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