A channel is nothing but one of the photoshop panels which store the colour information of document that is meant to be processed in the form of layers depending upon the mode selected. For instance, if RGB mode is on then the channel panel will show four channels by default, i.e., RGB, red, green and blue or if CMYK mode opts then the channel panel will show 5 channels by default, i.e., CMYK, cyan, magenta, green and black.
COMPOSITE CHANNEL:
This channel is a combination of all channels present in the channel panel. It always tops the layer of panels. It gets renamed by default according to the mode in use. However, one can change the mode easily by pressing on image option and then opting on mode to choose the desired mode, i.e., RGB or CMYK, etc.
COLOUR CHANNEL:
It saves the colour information of one specific channel present in the photo between 0 to 255. For instance, the area of white, present in red colour! Whichever appears to be whiter or brighter contains more of a red colour than the area which appears darker on a comparative note. This is similar in the case of green as well as blue channels.
ALPHA CHANNEL:
This channel is known to be the life-saver which temporarily saves the opted tools like marquee tool, lasso tool, etc., which saves a lot of time. To save the selection made, opt selection and then save the same.
LOAD CHANNEL AS SELECTION:
Firstly, any colour channel of choice must be activated and then “LOAD CHANNEL AS SELECTION” must be opted which will load that particular channel as a selection. To do the same ctrl/cmd should be held and then thumbnail must be chosen.
SAVE CHANNEL AS SELECTION:
Prefixing “alpha” and saving the channel is possible only if there is an active selection in the image just like in the picture shown above. Black area depicts the unselected area whereas the white area depicts the selected area.
CREATING A NEW CHANNEL:
This channels deals with duplicating the existing channel. There are two ways to duplicate the channel. Using the first method one can simply select, drag and drop the selected channel to create a new channel. The second method suggests one to duplicate channel by selecting a panel menu and then choosing to duplicate the channel.
DELETE THE CURRENT CHANNEL:
As the name suggests, it is used to delete or discard the channel simply. To delete a channel simply drag and drop that channel to the icon and it will get deleted. However, it must be kept in mind that discarding a colour channel may destroy the image used.
CHANGE IN THE SIZE OF THUMBNAIL:
To change the size of the thumbnail, choose the option “panel menu” and then choose “panel option”. Three distinct sizes appear out of which one desired option can be chosen.
TURNING OFF VISIBILITY OF A PARTICULAR CHANNEL:
By choosing the channel, present on the left-hand side, it can be made invisible. In the above image, we can see the result of turning off the visibility of red colour as RGB is turned off automatically!
Channels of photoshop fame are used to enhance images especially the portraits. They are grayscale images which store a variety of information.
