AuthorTopic: Dithering on Photoshop Question  (Read 28606 times)

Offline Privaterandom

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Dithering on Photoshop Question

on: February 22, 2010, 09:28:50 pm
Hi guys,

First time poster and first time pixel artist here.

I've just recently got interested in pixel related artworks and wanted to create my own works, but I'm having trouble getting my head round by one of its techniques.....dithering! O.o

I've read quite alot of tutorials based on dithering , but none of them are in depth to say how to create the pattern, well how to create as a gradient on Photoshop CS4 as show here - http://www.derekyu.com/?page_id=226

It has been burning my head as no one on the net has given a clean tutorial on how do this.

I would greatly appreciate if someone could to explain to me how to do it.

PR

Offline blumunkee

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Re: Dithering on Photoshop Question

Reply #1 on: February 22, 2010, 10:07:23 pm
I'll bet you he did all that dithering by hand in PhotoShop. I don't do much pixel art in PS so I couldn't tell you if there is some way to automate the process with some sort of brush or pattern library. PhotoShop is a powerful program so I'm sure there is. Even if there's not, dithering itself is pretty basic, just study the patterns and apply what you observe. Practice practice practice.

There are also a couple of good threads on dither technique:

Dither Patterns
Dithersmoothing

If you're looking for a program that can help automate dithering, try out Graphics Gale (has a $$$ and free version, dither support is pretty basic), or Promotion (only has a $$$ version, dither support is more advanced). Dropping PS just for auto-dither is a little extreme obviously, but both of these programs have extra features that PS simply lacks. Animation, in particular, is like pulling teeth in PS compared to these programs.

Offline Indigo

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Re: Dithering on Photoshop Question

Reply #2 on: February 23, 2010, 01:03:53 am
Most people dither by hand, and almost certainly thats what Derek did.  Even if you use automated dithering, it'll always need some hands-on touchup to make it shine.  With that said, here's a quick shortcut for dithering in photoshop.

I first defined an 8x256 canvas and applied a straight black-to-white gradient.


then indexed the image (via Image -> Mode -> Indexed Color) to 2 colors, black and white - and set it to pattern dither.


You then select portions from that image which you wish to use as gradient patterns (8x8 blocks), then define it as a pattern.  PS will automatically optimize the pattern.


Once you're done defining all your patterns, you turn on "texture" in your brush settings, select the dither pattern which you wish to use, and set the mode to subtract.


Now you should be set to go!  Just pick the pattern and paint.  If you're picky about dither patterns, you can define your own by hand of course.  This allows for painting broad areas of dither pretty dang fast.



Moving this thread to General Discussion BTW.
« Last Edit: February 23, 2010, 01:08:58 am by Indigo »

Offline junkboy

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Re: Dithering on Photoshop Question

Reply #3 on: February 23, 2010, 07:20:38 pm
That's quite a nifty method, Indigo.

I keep one or two layers with dither patterns (that cover the entire image) in hidden layers. That way I can ctrl+click the layer and get a dither-selection whenever I want to use it, instead of switching brushes.

Offline Indigo

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Re: Dithering on Photoshop Question

Reply #4 on: February 24, 2010, 01:39:47 am
never thought of doing it that way, but it sure is cool.  It seems like you'd need more than two dither layers though if you want to keep the dithering consistent with itself below 50% as well as above 50%  - since inversing the 25% dither will actually give you a 75% selection rather than the 25 shifted over a pixel.... if that makes sense.

I guess you could still make it work.  just depends on what color you're using, right?  just a bit confusing just using 2.
« Last Edit: February 24, 2010, 01:41:34 am by Indigo »

Offline Jad

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Re: Dithering on Photoshop Question

Reply #5 on: February 24, 2010, 03:27:13 am
Well I use junkboy's method, and I barely ever use anything other than 50% dithering (everything else looks icky to me and should be solved by texturing or lower contrast. "Should" as in 'that's one way to do it (that I like)

so I just use one dither layer that I tick on and off O: the layer system is inconvenient for other dither patterns, I think
' _ '

Offline Privaterandom

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Re: Dithering on Photoshop Question

Reply #6 on: February 24, 2010, 07:18:55 pm
hi guys,

I would to thank you guys for helping with this dithering business.

It is certainly a method that I'm gonna have to put a patience into.

If there's any other methods then please post them as I'm open to learn all kinds to with pixel art.

Many thanks. :)