problems with semi transparent parts

hi, i doing a texture with semitransparent parts, it look good in the photoshop (CS3) but when i upload it to sl the semitransparent parts become in white, i think i´m doing something wrong with the alpha channel becouse the semitransparent part is never showed in gray , do what i do my alpha is allways black and white , do any one of you knows a good tutorial step by step that xplane how to do the semitransparent part?, or can tell me how to do it right? i know many people have thesame problem ,please i really need help . tnx

semi transparent parts should be some degree of grey on the alpha channel, only over the parts that you are trying to make semi-transparent.... if it's showing white it's sounds like you don't have a separate alpha *channel...

dunno how you do it in CS3 but in PSP you can take the transparency layer of your merged image and create an alpha channel out of it by creating a mask using the current image transparency, then save the mask to the alpha channel.

Markus, control the alpha channel; don't let it control you. If you want any part of to be gray, simply paint it gray. There are, of course, many other methods at your disposal in Photoshop, including a whole array of ones similar to what Void is describing form PSP, but for now, give it a whirl with simple, good old fashioned painting. That will teach you what effects different shades of gray have on transparency. Once you've got a handle on that, we can talk about more advanced methods.