alpha transparency

[camner]

Perhaps a dumb question, but I can't find the answer...

psd and png format permit alpha transparency, that is, "partial" transparency. How does one create a partially transparent pixel in PE(2), and how does one alter the degree of tranparency? Lightness/darkness alters colored pixels, it seems, in a fashion parallel to what one would want with transparency, but I don't see how to use this concept (if it is accurate) in practice.

[Leah]

Among other things - painting on a transparent background with a brush at less than 100% opacity (or round the edges of a soft brush), setting a layer to less than 100% opacity...

[Richard_Lynch]

Here's a demo:

1. open a new image with a white background.

2. create a new layer.

3. fill the new layer with black.

4. reduce the opacity of the black layer to 50%.

The result will be gray, or a 50% mixture of the two layers. This is essentially what happens with transparency. Transparency can be affected with Opacity, and masking in the image, or as a transparency property for the image (which may be what you were talking about having to do with a PNG). I have a tutorial on transparency on my ps6.com website:

http://ps6.com/Tutorials/select.html

choose the transparency tutorial. In there somewhere is a demonstration where I use a transparent GIF to act like a shadow passing over a background. In that image, half the pixels in the shadow area are set to black and the other half to white -- and white is assigned as the transparent color. the alternating black and transparent pixels allow the shadow 'sprite' to pass over the background letting you half see through, and half darken the result. One of many uses.

OK?

[camner]

Thank you both. Thanks particularly to Richard for the detailed explanation/demo.