Halftones in Photoshop

[DROiD3o3]

I hope someone here is an expert at this halftone / dithering. here is my problem

Example: take this image

http://www.pomexport.com/P - Netherlands Fokker/PPC - Netherlands Fokker_4x.html

goto indexed colour/adaptive in photoshop ... cut down to 2 colours ... use dithering option

I'd like to have this 2 colour "poster effect" as well as to be able to specify the size and shape [elliptical instead of square-pixel] of the dither/halftone. [upping the resolution will be necessary .. of course :] ]

yet i cannot work out how to reproduce the effect of the first example using the bitmap/halftone option.

Can someone prove to me it's possible or put me out of my misery!

Thankyou :]

 

[blueark]

When you go to Indexed Color, what settings are you using?
* Is Forced set to "Black & White"?
* Is Dither set to "Diffusion", and what amount?

Converting to bitmap using the halftone option will almost certainly give you a different result, as it is a different dithering technique. Are you creating artwork for print? If so, why don't you just use the diffusion option? Bitmap mode behaves differently in print than other color modes. Instead of the printer imposing a half tone pattern on it, the image data remains more intact. If the resolution is high enough, you won't see the square pixel effect.

You could also experiment with increasing the resolution first, then using the color halftone filter (you may want to work in grayscale). Maybe add some noise before using the halftone filter?

It's not clear exactly what effect you're looking for, as the two dithering methods (diffusion and halftone) work on very different principles.

 

[DROiD3o3]

sorry .. i should have told you all what its for .. its for screenprinting so i need the smallest white dither pixel/ellipse needs to be about 1.5mm.

OK so what i make of your [helpful!] repsonse is that halftoning will produce a different effect [in my experience worse] quality than dithering.

Is there a dithering plugin perhaps that uses round dots instead of square? [if I up the resolution of the orig image]

ps. using photoshop 5... options are just as stated before