RGB Help PSE

[JohnTravers]

Hi All,
I'm new so go easy on me! Briefly about me... I've worked as a design eng using CAD for 20yrs & never really touched on the graphics side of which I have very basic knowledge. I'm only really about 6wks into PSE (6.0) & bought the book 'The missing Manual' for reference (which I'm slowly digesting.. emphasis on "slowly" here as I'm over 50, I think my brain is growing something like a Gaussian forcefield.) I typed a search for RGB and landed on a threid about "colour space" which turned my Gaussian forcefield intae a Radial one which continually revolves! I'm trying to get a better understanding of RGB, if anyone could answer the following ?'s I'd really appreciate!! (they may be stupid but..)

1. Is this where beams of light Red,Green & Blue overlap and produce White?
Value 255 of each colour = full Saturation of that colour? If so would true white be 0,0,0?

2. Where is Yellow & what would be the value for full saturation here?

3. Is there any real easy ways to determine values for warm/cool shades of colours?

4. Would it be easier to use colour swatches as staring points and tweak values from there?

Many thanks..
John

[TommyO]

Hi John and welcome ! Hope you enjoy the forums.

This won't be complete, as there are books for that. And keep in mind, we describe color as it is interpreted by our eyes and brain; no physics here. So, here it goes....

1. Yes, RGB is just that. Red, green, blue mix to create other colors. When each are equal, we get white; if at full intensity, it's bright white (255, 255, 255). Black is the absence of color or light, and is represented as 0,0,0.

2. Yellow is a mix of red & green. Depending on the intensity, you get differing shades. Fully saturate, you would have 255, 255, 0.

3. The easy way is to memorize what warm or cool represent, experiment with adding these tints to existing images in transparent layers. Most applications now have sliders designed around "warm" or "cool". We tend to think of cool as more blue, and warm as more yellow/orange.

4. Yes. Nothing wrong with that; that is what they are there for. At least use them to learn what they represent numerically.

Once you progress through the months and years of the learning curve, it will all seem elementary.

Good resources for you:
1. Real World Color Management 2nd Ed, PeachPit Press, Bruce Fraser & Chris Murphy.
( a great book, very technical, good for an engineer )
2. Cambridge University, tutorials on color and digital imaging.
( written, not video, all free )

[JohnTravers]

Tommy, Thanks fur the quick reply!

"Yellow is a combination of Red + Green" this must be surely be a new colour algorithm.. Primary + Secondary = Primary! I'll smile the next time I've got a real sable in my hand! (It must be real difficult for digital artist's creating from scratch!)

I'm 1st going to play around in PSE for a while as you suggested and when I feel less blurred I will have a look at the link you've posted..but no furra while.. yin step et a time.. eh?

Really appreciate yer comments!

If anyone has any methods concerning RGB colour selection I'd welcome hearing them!

Thanks agane
John

Pee Ess A' micht be sookin a dummy fur quite some time

[TommyO]

Here are a few color tables that may help.
On the left the RGB Color Space; on the right the CMYK (another alternative).
RGB are the additive primaries; CMY are the subtractive primaries.
Again, the book is a good one.

[JohnTravers]

Tommy,
Thanks for these..they will help!

[Kraellin]

hi john,

RGB comes from the television industry. that light in your television screen (or computer monitor) is produced from three electron guns (yes, they're called guns). one is red, one blue and one is green. these three guns fire a beam at the backside of your screen and light up the phosphor coating painted on the back of the screen. these guns start shooting at the top and work across, line by line at a very fast rate. the phosphurs are there to hold the light for a short while until the beams from the guns can refresh them once again in their next pass.

so, in the video and digital world, rgb are the primary colors. in the printing world it's cmyk (cyan, magenta, yellow and black), but that's a different story