Need tutorial for masks and channels

[Doug Nelson]

By paulette conlan on Monday, July 09, 2001 - 03:05 pm:

I'm trying to learn how to use channels better. On the last challenge I was particularly interested in mig's description of how they were utilized . I have some books which seem to be pretty descriptive and sometimes I get it right but I always feel like I'm doing it by the seat of my pants and not really comprehending what's going on.What is bothering me particularly is how after manipulating the channels you get back to a normal layer palette.My layer palette is grayed out and the image shows as transparent even though I can see it in the image window.Thanks Paulette

By Raymond McKinley on Tuesday, July 10, 2001 - 05:58 pm:

Paulette

Check out this link
http://graphicssoft.about.com/cs/pho...asks/index.htm

Raymond

By Paulette Conlan on Tuesday, July 10, 2001 - 06:43 pm:

Thank you for the link. Looks like an excellent resource. Can't wait to try it out. Paulette

By Vogonpoet on Tuesday, July 31, 2001 - 06:00 pm:

Here are a few links for channels ~Vp~

http://www.sketchpad.net/channels1.htm

http://www.sketchpad.net/channels2.htm

http://horizon.nmsu.edu/alphachannels/

http://www.icdc.com/~ncassway/comput...p-channels.htm

http://www.webreference.com/graphics/column41/

http://extropia.widexs.nl/tutorials/..._channels.html

http://www.arraich.com/ps6_tips_channels1.htm

http://gurus.onlinedesignschool.com/...xplained.shtml

[Doug Nelson]

An old thread, but a good one. Any more masking tutorial links?

[john_opitz]

Had to edit this. Went off line for coffee.



Here's a good book on it.

Photoshop Channel Chops

What I do.....to make a mask is. If I'm working on a rgb image. Look into the channels(lets say the red). Duplicate the red channel to a new layer(right click the mouse on the red channel. Click duplicate layer). When the duplicate channel box comes up. I rename the alpha channel(let's say "Jennifer with chip on her shoulder") On the destination document, click "new". For name, I name it, whatever the mask is for. Click o.k. Apply a curve to it,(go to image>adjust>curves). Make the area you want to select"white" or "black"and the area you want to knockout the opposite color. Then use the magic wand to select the area........ This is just the start of the mask.. Some masks can be complex. Like, lets say the jennifer pic. Where its easy to use this method for selecting the hair,face,hand. When it comes to the sweater, its a different story. So in cases,........I should say images like this, after doing the above. In addition to this, go to quick mask mode and continue(you have to deselect the selection made with the wand) to paint on the image to finish making the selection(mask).... In the jennifer pic. It would be the sweater your painting on.There are other ways as well.... I would save this channel in a folder "masks".(I do this because their are photographers, who when they "flatten" images. They don't like to do "save as".....I guess, that's too hard). Naming it, whatever the mask is for..... psd., pdd. format, alpha channels. Then open the file ,load it, into the file its made for.

p.s. Man.... Posting this..... I don't think my first marriage,.....Lasted this long.

[john_opitz]

One other thing. You can duplicate the file(as a new one). And convert it to CMYK and/or LAB and look for a channel that is better for making a mask as well. The black(cmyk) is good for this and in LAB it's the "a" or "b" channel. So. This way you have ten channels to choose from, instead of 3(rgb) or 4(cmyk).