On Sun, 11 Apr 2004 05:37:58 -0700, wrote:

I believe anti-aliasing makes an edge look smoother by making the pixels fade out to tranparency from an edge.

Feathering blurs the pixels.

1) What is actually happening to the pixels?
What are the similarities and differences between anti-aliasing and feathering? I understand visually the difference. But how are the pixels changed?
2) Also, does using the gaussian blur have the same effect as feathering? I'm asking this because I read a method that lets you see how much feathering is being applied by using the gaussian blur. I want to know if there is a difference in how the pixels are treated.

The method is as follows:
Step 1: Make a selection
Step 2: Change to quick mask mode
Step 3: Use the gaussian blur filter, which effects the selection and not the image. You see the blur on the edge of the selection.
Step 4: Get out of quick mask mode.
Step 5: Do whatever it is that you need to do with the selection.
Sincerely,

Robert Dawson

Feathering uses transparency. For example, If you take two layers, white on top, black on bottom. Apply a mask to the white and use the marquee selection , round or sqare, doesnt matter. No feathering. Hit the delete key and u got a perfect sharp edged cookie cutter hole where the black will show through.

Now take the take the lection again and apply as much feathering as you like, say 50 pixels. you will then see it will taper off into gray.

so lets say a round selection with no feather would be a perfect punch hole.. a feather of say 50 will reach outside the outer edge 50 pixels and use graduated transparency. That is exactly how to create a vignette.

antialiasing is just pretty much blurring hard squared blocks to give it more of a rounded shape for text and graphics mostly so things dont look so blocky...

Two totally diffrent animals.. Hope this makes sense to ya.. look at a vignette of how it gradually fades,

MathDreamer

Replied in the following topics

anti-aliasing vs. feathering