[quote
I did a test with a can of Fire Red and a can of Black ( both high gloss versions )

I took a sheet of wood and placed 10 drops of red on the sheet.

Then I took the black paint and dropped 1 drop on the first red spot, 2 drops of black on the second red spot, 3 drops of black on the third red dot etc etc etc.

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Something tells me thats way too much black to red ratio for the color you're aiming for. I had some paint tinted for home use and the amount they added to a gallon for a big shift in shade was something like 20 drops. Been a while since I had that done so I don't remember the details, I just remember being shocked that they added so little.