Color information

[MahaB82A]

If you select RGB, Info panel shows what are the colors are there. For example if you select AFTER EFFECTS Info panel shows: 

R:147

G:26

B:26

A:225

Color information

What is the purpose of having separate R, G, B?

[Mylenium]

https://en.wikipedia.org/wiki/RGB_color_model

Mylenium

[MahaB82A]

What is the purpose of having separate R, G, B?

[Mylenium]

You have to go back to how computer graphics started out as CRT tubes and there were three differently colored dots for each pixels that would be stimulated with an electron beam. That's where all this comes from.

Mylenium

[MahaB82A]

That means RGB is evolved from R, G, B. So that R, G, B is not much useful currently. 

[thepixelsmith]

Are you asking why you have the ability in After Effects to view the  invidual color channels in the Comp panel?

[MahaB82A]

Yes, you are absolutely correct.

[thepixelsmith · Accepted solution]

It's a preview tool just like being able to see the alpha information in the comp window.

Sometimes there may be an abberation that only appears in one of the color channels so being able to isolate and preview them individually may help with troubleshooting. 

When color grading or correcting it can be helpful to isolate the preview to get a better idea of the color breakdown of your composite video.
The same function is available in most video and graphics programs, they just call it different things, like how Photoshop calls it the Channels panel.

[MahaB82A]

Thanks for the help.

It is highly appreciated if you could upload an example video on this issue.  

[MahaB82A]

Is this video shows typical this type of issue?

Shift Channels Effect

[thepixelsmith]

No that video is a  tutorial on creating a glitch effect to stylize your video. 

Just think of that option as a way of previewing the separate colors of your video. 

Depending on the type of work you do you may never need to use it.

[Rick Gerard]

There is no color in the color channels. Color is created when you mix different values. If you want to see what the Red channel looks like, you can just select the Show Channel options in the center of the Composition panel.

If you want to judge the color values to see how much red there is in a color channel, the best way to do that, and the way someone that professionally does color grading does it, is to open the Color Workspace and pick the appropriate scope display. 

Personally, I almost always work in at least 16-Bit color, so I have my info Panel set to decimal. It's easier for my mind to interpret what I see in the Infor panel that way, and is also the easiest way to handle color if you are writing an expression.  [1, 1, 0, 1] is 100% yellow with no transparency.  [0, .5, 0, .5] is a Dull green with 50% opacity. The info panel is very handy for checking incomplete keys because anything that is not 0 in the A (alpha) value means you have some contamination in your keying, and you need to make some adjustments. 

[MahaB82A]

What is meant by "There is no color in the color channels".?

[Rick Gerard · Accepted solution]

All channels are values from darkest to lightest. In 8-Bit color, there are 256 possible shades of gray for each channel. The values are displayed with numbers from 0 to 255. Change to 16-Bit color, and you now have the maximum possible number from 0 to 32,768 per channel. Change to 32-Bit color and the count now changes from 0 to 1, but it is calculated using floating-point, which means that there are 16777216 different values available because of the number of decimal places available, so that's an almost unlimited number of distinct values for each color channel. 

Colors are produced when you calculate the difference between the available color channels. If you look only at the value of a single color channel, there is no color. If you look at the red channel and ignore the other channels, the channel can only get brighter or darker. Black or White. 

You could artificially supply zero values to the Green and Blue channels and create a red display on your screen, but if you only look at one value, you only get something bright or dark. You have to calculate the difference between all three channels if you are going to get color. Otherwise, all you are going to see is black and white. It is often useful to look at the different values as an image, but unless you artificially add in a Zero value for the missing colors, you just get a black-and-white image.

Did you follow all that?

[MahaB82A]

Thanks for the detail explanation.

According to explanation, I assume to get more prcise color, option should be more than 255.

   

[Rick Gerard]

The info display is not linked to the color depth of the project unless you select Auto Color Display.

The actual number of colors available depends on the Project Settings. I keep mine set to Decimal because I can visualize the importance of the color values and compare values easier because that's the way I usually work. 256 in 8-Bit is the same value as 1.0 in Decimal, but if you are working on a 32-bit project and have overdriven the brights on any color, the values will be above one. Any render to a lower bit depth format will result in a severely clipped color. It just keeps things precise.

[MahaB82A]

32-bit project means, should project specification be given in a project?