Preserved Topic: channel (Page 1 of 1)

i have read some lessons (include here),but they only explain
how to make some effects in channel,dont exactly explain what is channel,how it work ,.......i really want to understand more about channel ,can anybody tell me more?

i love beatles

As I understand it a channel is a height map. white means the highest point and black is the lowest, shades of grey are the in between levels.

A channel is also great for saving selections. When you have a selection open a new channel and fill it with all white. You can come back later and make the same selection.

I'm still a n00b at Photoshop so my idea of a channel is probably only a beginning.

Well, I've been bitched out before for calling a channel a "height map"... "white is high and black is low" is only partially correct for height maps actually, because you can click the invert button of the lighting effects and make black high and white low...

I'd say think of a channel as "storage". It is a grayscale "image" (I'm putting lots of stuff in quotes because people get really pissy if you describe something too specifically when it should be generalized) that is part of a psd file. An RGB image as a standard has 3 channels with it to begin with. Red, Green and Blue... and what is in them defines what is in the image. In each channel, white is where the most color is, and black is where there is no color. So, if you have an image that is filled with the color red, your channels would look : completely white in the red channel, and completely black in both the green and blue channel.

When you add new channels, you are creating an empty space, a black channel with nothing in it. Things you add to it are white... it's like if you ever took an art class, the white is where there is matter, and the black is the negative space. Greys define transparency in this situation, where something is only partially visible. Like Lao said, "A channel is also great for saving selections", but it's more than just saving selections... you can also use a channel to create the selection... anything you make in a channel which is not black will be selected if you ctrl-click the channel (or load selection from it), so you can make a new channel, create a white box and then adjust it with filters and curves and what not and create a selection you couldn't make with just the lasso and marquee tools.

It's very hard to describe a channel because it has nearly ulimited uses. But, if there was ONE thing in Photoshop that should be understood over all the others, I'd say it was channels.

and the flaming will proceed......

....

.... now.



[This message has been edited by Human Shield (edited 07-30-2001).]

check out these links for all you ever need to know about channels
http://www.sketchpad.net/channels1.htm http://www.sketchpad.net/channels2.htm http://horizon.nmsu.edu/alphachannels/ http://www.icdc.com/~ncassway/computer/photoshop-channels.htm http://www.webreference.com/graphics/column41/ http://extropia.widexs.nl/tutorials/photoshop/what_are_channels.html http://www.arraich.com/ps6_tips_channels1.htm http://gurus.onlinedesignschool.com/beginners/channels-explained.shtml

That should give you a good foundation to Channels - Happy reading ~Vp~



[This message has been edited by vogonpoet (edited 07-30-2001).]

Excellent vp

thnx

nj

If you can understand my english, maybe it works a little..


.-rotate script by Mr.Max

VP, thanks for the link to WebReference. Been there before, but never really went through the site. Never thought of using View > New View for working on a seperate channel. No more working blind. Nugget of Joy.

Thanks.

still waiting for that wispy thing! heheeheh

the definitive tutorial!

en,quite good site

i love beatles

A few days ago I ran into a problem with BoL. Nothing I can't handle, though. But suddenly I find myself having to get used to a crappy trackball again... Wispies, once I get done unpacking and finish up BoL (shouldn't be much longer).



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I, Warjournal, Techincal-Slop Author Extraordinaire.