ah well - vector and bitmap[pixel] are different.. right?
a pixel gradient such as you have in PS is not made from incremental steps that produce bands, its a continuous 'stream' of pixel matrix, dithered or otherwise
the steps that produce the bands are a vector 'limitiation' - vectors are mathematically calculated objects which show up as the bands..
one reason why it's common to use bitmaps as texture
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Nothing lasts forever...
That is correct.
A couple thoughts on banding in vector-based apps.
If the
- re is too little color shift, banding will be more apparent.
- Banding is worse when using a single color (say only the K component) and dropping only 15% or less from one pole to the other over a long enough distance.
- You will almost always have a step in the transition if you drop to white (0,0,0,0). So with a K only gradient, stop at 5% or less (but not 0%). The film at 150 lpi or greater will be almost white (paper color) at 5%.
- Outputting to a level 3 postscript produces "smooth shading" which boosts the inherent limitation of the vector gradient from 8-bit to 11-bit. The result will be a smoother interpretation of the bitmap dump that hits the output device if going to a rip. I.e., a postscript laser printer may not show how smooth the gradient can be, but a rip will. Doesn't help much on lower-end digital printers, but does with better equipment.
- If at all possible, include more than K in a gradient. A richer black once output will likely print better than it looks on-screen because of the screening in the rip.
There is a reason that designers often resort to PhotoShop or another good image editor for gradients--which one can also do within XDP. With added noise and a low amount of gaussian blur, a gradient has a better chance of avoiding banding noticeable, especially if combined with output to a PS level 3 device.
Enough babble for now. Take care, Mike
thanks Mike..
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Nothing lasts forever...
Useful info, Mike. Thanks.
the first point should be--but I cannot edit the post--is:
If there is too little color shift, banding will be more apparent.
Sorry about that and thank you for the kind words.
Mike
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