I have a frontosa (C. gibberosa Mikula) fry that likes to sleep in the cleft of a rock near the front of the tank. When fronts go dormant for the evening, they adopt a dark color pattern and crank up the blue pigment that covers their entire body (most noticeably in the white stripes). I noticed this little guy was fond of this perch; so, one night before turning off all the lights I set up the tripod and dialed in my settings in anticipation of him being here the next morning. When I turned on the lights that next morning, he was in the expected location and I was able to snap a few pictures before he became fully alert and scurried off.
Here’s a pic of their light color mode (their color can range anywhere in between both extremes):