Mennon Set of 2 Gray Card's size 4"x6" and 6"x8", 18% Gray / 92% White
Set of two flexible check cards takes guessing out ofsetting perfect exposure and color balance, that can onlybe archived with high quality Mennon Gray Cards with theuniform spectral reflectance, regardless of wavelength,color or intensity of the illumination. Each card has twosides: one side white and other is gray. The gray side usedas a reference area for exposure metering while the whiteside enables correct white balance that is so important indigital photography.Specification:*  Gray side: Reflectance 17.8%; Density 0.74  *  White side: Reflectance 92.0%; Density 0.036  *  Max. deviation of reflectance: 2%  *  Max. error in exposure measurements: 1/8 of F-stop  *  Card sizes: 4"x6" and 6"x8"  *  Core material: high density paper based composite  *  Gray side material: special paper with spectrally flat 18% coating  *  White side material: special paper with spectrally flat 18% coating