Most geckos do what they call firing up. When they are fired up they typically look their best. Humidity, amount of light, moving around and stress can cause them to fire up. When I got to take pictures of my cresties I will typically put them in containers with a moist paper towel and then put them in a dark place for a while, usually a stryofoam box.

For example this is one of my females.
Usually:


Fired up:


one of my males.
Usually:


Fired up: