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So a color laser printer do dithering?


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I was thinking about a color laser printer - didn't know about this issue - thanks

Color printers are known to.

To add onto this, what about monochrome laser printers? Where is the yellow coming from in those cases?

Shouldn't we be able to control a printer on the pixel (dither) level in the first place?

Also a paper about halftoning on laser printers:

http://users.eecs.northwestern.edu/~pappas/papers/pappas_ist...

I have never used a laser printer that did implement anything like this, the usual halftoning sucks. Once I handcrafted a file with a 600 dpi Floyd-Steinberg image (the native resolution of the printer I hadd) and it resulted in much better results, I didn't bother calibrating the gray levels though.


That sounds like fairly specific usage. My color laser has served me well for document printing, both color and black and white

That's laser printers

Are laser printers still a ‘thing’? I recall having one as a kid and it just wiped the floor against any InkJet printer I’d used - holy crap.

It was limited to black and white though.


Hey, laser printers do it

Apropos. I just invented 3D-way to implement color laser printer. Firstly you have enclosed chamber with transparent top. Then you blow some color powder in the chamber. Maybe you apply some electrostatic forces to speed up the process. When the dust has finally settled on the paper, you just zap it with laser. The melted powder adheres to the paper at appropriate points. You suck the loose powder back to its container and repeat the process with next color.

This is clearly more economical construction compared to Xerox-style laser printer. It collects the powder firstly on separate surface, heats that and then presses adhered shit to the paper.


You probably won't find one as compact, colour laser printers are basically 4 monochrome laser printers in a row with different colour toners loaded, the process doesn't lead itself to having small toner catridges on a moving head like how inkjet work. This is a plus and a minus. The minus you've found, they're pretty bulky, but reducing moving parts also has pluses for durability and lifespan.

Almost everything I print is color, usually things like signs, decorations, letters with photos, etc.

If I printed documents regularly I suppose I'd probably want a laser, but it's not a very common thing for me, maybe twice a year, generally 1 or 2 pages at most.


Except most people's color printers are inkjet instead of laser, so the DPI penalty more than compensates for the 3x gain with color.

The problem comes in the thin lines. If they don't fall exactly on the hardware pixel boundaries they will vary in weight. If you can get the printer to think in monochrome instead of some larger dithering cell you have a chance.

A simple black and white laser printer can do that. I had one for about a decade until I bought my color laser. It worked great, and only needed toner every 2-3 years. I regret getting rid of my black and white laser.

I find the Xerox (formerly Tektronix) Phaser solid ink color printers to be pretty awesome in this regard. They print fast and produce a glossy, professional-looking color print. I think the main problem is that they require more energy over the long term than a comparable laser.

It depends on what you pay for. High speed color banner printers that use inkjet are faster that color lasers. That is partly because there are few large banner laser printers.

Lasers are faster because they compute the exposure pattern, then expose the drum in a written band that then goes past the toner brush(a magnetic low force brush) where toner is attracted to the pattern defined by the laser or LED beams = 1 color, squashed, into color 2, color 3 and black. Once computed you can print a page every 2-3 seconds until toner or paper gone. Inkjets lay down a colored stripe, advance the paper, lay down another, advance. They can be made faster and bidirectional. You could make a banner printer that was cut down to 8.5 x 11 that would print a page a second


Laser printers (color ones) are (were?) required to have some sort of built in imperfection because they were too good and could be used for counterfeiting.

I wouldn't be surprised if this eventually is a requirement for cameras, you know, just because law enforcement wants it.


And how do they get printed on a monochrome printer like a laser?
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