tinting and tinting percentages/strengths

[freedda]

I was just looking at pigment info. in the Artist Handbook. They show spectral curves for different pigments, both full strength and at certain percentages of tinting strength.

I notice that when tinted, many pigments have a higher reflectance value and also the values for different colors within a pigment are more varied. For example, at full strength Ultramarine blue has a fairly low-value, flat reflectance, with only a slight increase in the blue range, but at 2% tint the same color has much higher blues and much lower yellows and reds.

My question is: what do the percentages of the tints mean, and how would I apply these. For example, would a 5% tint mean I'd mix an ink at 20 parts to 1 part titanium white? Or 10% tint would mean a mixture of 10 to 1 for color ink to titanium white? OR?

Thanks, David.