Photoshop alpha??

[jag5311]

Could someone explain to me what alpha means in terms of photoshop. Such as loading an alpha panel or whatever. That just confuses me. This link, uses it alot, and I don't understand much.

http://www.optonline.net/Call_For_He...736042,00.html

Thanks
Bryan

[Jixxy]

There is an alpha channel palette in Photoshop, usually located in the same set with your layers and paths palettes. It basically breaks down the image so you can see it in it's seperate colors. You can also create cunstom channels and use them as masks.

[jag5311]

Ok, now the strong newbieness is coming out of me Lets say you do create a custom channel, would you be doing that as a custom color. I have seen the alpha window before, and i believe it has the normal picture, then a red version, blue version, and green version. Would a custom channel be a different color? If so, what is the purpose of using it as a mask

Thanks
If you want to reply with, OK IDIOT, that would be fine as well

[theGuest]

There's no need for anyone to call you an idiot jag.

RGB Channels contain 2 specific things:

1) a composite of all 3 colour channels (RGB), plus each separate colour channel independant of the composite.

2) alpha channels. These are used for a few various functions. The main one being as a way to create/edit/store selections that are used in your document. Another use is as a 'texture channel', loaded and applied through the "Lighting Effects Filter".

Alpha channels can only contain 256 greyscale shades -- which include B&W.

All channels can have filters/plugins applied to them to some degree -- some more than others.

If you were to run the Clouds filter on a new channel, and ctrl-click the channel, you would effectively be loading the selection of the lightest tones in the channel -- i.e. highlights. You could then return to a layer and apply a filter or other effect/edit to the area of your image that is being selected. You could also inverse the selection (Ctrl+Shift+I) and effect the darker shades of the image instead.

Other types of channels are temporary ones, such as for the Quick Mask mode... and reference ones, that belong to a layer containing a Layer Mask.

I suggest you do some experimenting with the channels and get a good feel for them. They're invaluable in many ways. And don't be afraid to tackle the HELP! files on this subject too. There's some good info in there for anyone.