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I'm aware that with an inkjet printer, printing a higher dpi image will require a huge amount of additional ink.

However I was wondering in the case of a color laser printer, do we need more toner to print a higher dpi image?

For example, printing a full-page photo in 300-dpi on a 8.27 * 11.69 paper would cost 8.7m dots, whereas printing that same image using 2400-dpi would cost 556m dots.

Is it true that printing a 2400-dpi image would cost roughly 60 times the cost of the same image in 300-dpi?

Or is the cost much much lower, like say maybe just 20% more than what a 300-dpi would cost?

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    Probably not 60 times, but it will be more. Since not every particle of toner is used for high-DPI printouts, let alone used at all, it's probably not a simple calculation, and will come down to averaging out over the life of the cartridge.
    – user3463
    May 17, 2012 at 23:56
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    More dots doesn't mean more ink. There may be more dots per square inch, but the dots are going to be much smaller. At the end of the day, you're still covering the same surface area with ink. The image resolution is just higher, allowing more details to be expressed in the same area. As an example, if you print a greyscale image using different resolution halftone patterns, there still has to be the same ratio of of background(white) to ink(black) for the halftone patterns to show the same shade of grey. And a higher DPI might actually be more efficient. May 18, 2012 at 0:00
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    And it doesn't matter what kind of image you're printing, when you zoom in on it close enough, it's all halftone patterns (since you need to simulate continuous tones using a fixed number of colors). If I were to tell you to cover a wall with a checkerboard pattern, does changing the size of the checker pattern change the total amount of paint you use? Does changing the number of colors change the total amount of paint used? Also, most paper can only hold so much ink. If a high DPI image really used 2X the ink, not only would the color be different, but the paper would probably soak through. May 18, 2012 at 0:15
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    @Pacerier: What "overhead" are you talking about? There's no "overhead" in printing a dot. All you need is the ink to fill the area the dot covers which depends on the size of the dot. May 18, 2012 at 0:18
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    On some printers, in solid color areas, there will be a bit more overlap of the dots at higher resolutions. Typically, about a 10% increase in ink/toner consumption is reported for each doubling of resolution. It's not a huge amount as the same area gets filled with ink. (The manual for my black and white laser printer claims 1200DPI will use about 12% more ink than 600DPI.) May 18, 2012 at 0:22

2 Answers 2

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There are 2 factors here: the dpi of the image and the dpi used to print.

The dpi of the image does not affect the printing cost at all, a higher dpi just means the print will take longer as the PC (and possibly the printer) has more processing to do.

As far as I know there are no lasers that print 2400 dpi. Some very rare ones can print 1200 dpi, but most are limited to 600 dpi. For example, the Xerox Phaser 7760 ( http://www.office.xerox.com/latest/776BR-01.PDF ) can print 1200 dpi, but its best photo quality is at 600 dpi, where it can use variable spot sizes, i.e. it can vary the amount of toner deposited in each dot. At 1200 dpi it can only produce 1 spot size. The new Phaser 7800 claims "true 1200 x 2400 dpi resolution", but I have not seen any details about it. At higher resolution the toner dots are smaller so the cost difference is negligible.

The same goes for inkjets. I believe some Epsons manage a real 1440 dpi, but that's the highest. All higher dpi specs are for "effective resolution". This compares the printer's optimised haltoning with standard rotated-screen halftoning, and indicates how well the printer prints shades of colours and hence photos; it does not relate to the real resolution. Again, some can vary their spot size, like the Epson Stylus R3000 ( http://www.epson.co.th/epson_thailand/en/printers_and_all_in_ones/inkjet/product.page?product_name=Epson_Stylus_Photo_R3000 ). Higher resolution means smaller dot sizes and no major increase in cost.

Another thing to consider: if, at 1200 dpi, the printer put 4 times as much ink on the paper as at 300 dpi, that would make the paper completely soaked in ink and the result would be unacceptable.

As an aside, there is no real point in printing a photo at more than 300 dpi as the eye will not be able to tell the difference. Note that I'm talking about the resolution as printed, i.e. for a 6" x 4" photo you don't need more than 1800 x 1200 pixels. When buying a camera, 6 Mpixels is adequate for an A4 (US Letter) print. Higher resolutions are only needed when printing larger sizes, or when you're going to crop the photo.

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    Max useful resolution depends on the distance at which the image will be viewed (and the source image of course). 300 dpi is fine for most applications, but you can begin to see high contrast halftone patterns at probably 8~6" away from the face. Giclee art prints generally are about 1440dpi, and there are probably other niche applications where higher resolution printing is required. But otherwise your answer is spot on. May 18, 2012 at 1:38
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    @Lèse majesté - With Giclee you're talking about printing at 1440 dpi, while my comment was about the number of pixels in the image. Unless the printer can produce 16M colours per pixel, it needs to print at more than 300 dpi for a 300 dpi image, so it can generate the necessary halftones. And, of course, for art prints you may want to increase the image to perhaps 600 dpi, but certainly no more than that.
    – hdhondt
    May 18, 2012 at 1:56
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    we had one of those thermal dye sublimation printers, and because it could VARY the ammount of ink at each pixel, 300x300 looked beautifull, but most of this stuff cant vary :-(
    – Psycogeek
    May 18, 2012 at 2:12
  • The question is about printing resolution, and also the claim that 1200 dpi printing resolution affects the amount of ink has to be proven. It should not happen, since drops become smaller, or dots at lower resolution result from depositon of multiple, smaller droplets (the hi-res ones).
    – FarO
    Sep 6, 2017 at 8:28
  • Why the downvote? I stated that "the cost difference is negligible"
    – hdhondt
    Sep 11, 2017 at 23:10
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The major cost of ink and toner is simply how much of the page is filled. Changing the resolution only changes that slightly.

On ink jet printers, smaller dots tends to have a bit more overlap and less empty space at the edges. This results in about a 10% increase of ink used per doubling of resolution on the same printer -- at least until someone invents a way to print "square dots".

However, a printer with a higher resolution will tend to use less ink than a printer with a lower resolution if they are both printing at the same resolution. Higher resolution printers have more accurate drop placement and so need less ink overlap to ensure complete coverage.

This is a good introduction to resolution considerations on inkjet printers.

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