18% Grey Card

[mongo66]

is there a way using Adobe Photoshop to manipulate the settings and levels to "homemake" an '18 % Grey card' ???????? I have a book w/ DIC #'s of different "grey" colors; DIC 543 is an almost looking 18%, DIC 544 is a Dark grey? WOuld this be helpful to be able to use this a a base line????????

[Gary McDuffie]

For one thing, you'd have to be sure your printer was setup to replicate the generated grey card exactly as it should be. They aren't expensive, just order a good card.