To figure out digital color formulas for MS Paint program similar to your favorite markers, pencils or watercolors, either scribble or paint on dead white paper, then scan, and import the scan into your MS Paint program and let the eyedropper tool figure out the formulas for you. Then save the formulas in a WordPad document and you have your favorite colors ready to go.
For example: I scanned my favorite marker colors. I wanted the approximate colors. Cap colors are not the exact color usually, but it indicates what's inside and is a more intense hue. I cleaned my scanner screen, set the resolution settings to color at 300 dpi (most magazines use this level), removed the lid, and covered the markers on the screen with my black screen box (bottom of shirt box exact size of screen; lined with black cardstock) and scanned them. Then I imported the scan into the MS Paint Program.
Click on eyedropper tool on sidebar, move cursor over to the area on the marker lid with the most light on it, and click. Move up to "colors" on toolbar, then scroll down to "edit colors" and "define custom colors." The color formula should pop out for you.
Here are three color formulas that I came up with for the markers above. Mind you, these are close to the right colors and will change depending on where the eyedropper is used on the scan. Save the ones you like best.
Hue, 226; Red, 187
Sat., 75; Green, 125
Lum., 147; Blue, 146
Hue, 34; Red, 228
Sat., 147; Green, 216
Lum., 174; Blue, 142
Hue, 43; Red, 160
Sat., 27; Green, 162
Lum., 141; Blue, 138
Click on "color," "edit color", then move the cursor over to one space of "custom colors", click, open "color definitions," then type in your formula, "add to custom colors" and click ok.