Many inks are metameric, hence the need to check/match under controlled lighting. What is a perfect match under incandescent light can often become a complete mismatch under daylight. Don is correct that the lighting conditions need to be defined in order to color match anything.
And FWIW, metamerism can be a good thing. Because of this it's possible to conclusively identify some tough shades by examining them under different light sources (such as UV.)
However, for comparing stamps to Munsell chips, the only way you'll get a good result is to do it under daylight (or per the Pittsboro guide, "north light on a bright cloudy day and never in direct sunlight,") or its next-best equivalent, an Ott light. Those were the conditions under which the chips were selected for the guide, so the conditions under which the stamps must be compared.
Of course, stamps change in color due to different printing runs, 100+ years of exposure to the elements & handling, etc. No set of chips will be perfect, but IMO the Pittsboro set is a very reasonably-priced, accurate set to get you in the ballpark. It would definitely eliminate many of the pink & pigeon blood wannabes listed on
ebay, as they won't be even remotely close to the chip color.
Posted 04/10/2015 08:05 am
