Hidden colors in grey wall.

Exposure Date: 2015:04:08 19:32:26;
ImageDescription: OLYMPUS DIGITAL CAMERA;
Make: OLYMPUS IMAGING CORP.;
Model: E-30;
ExposureTime: 1/250 s;
FNumber: f/3;
ISOSpeedRatings: 200;
ExposureProgram: Aperture priority;
ExposureBiasValue: 0/10;
MeteringMode: Spot;
Flash: 8;
FocalLength: 28 mm;
Software: Adobe Photoshop CS6 Windows;