Hangar Lighting is a common topic discussed here and a very important one for anyone building an airplane indoors.
There are many factors that go into a quality lighting design but one often overlooked is Color Rendering. CRI, Color Rendering Index, is a number from 0-100, 100 being the most true representation of all colors as viewed with the human eye.
Traditional older lighting sources still commonly found in our hangars are T12 Fluorescent and Metal Halide. Both of these sources have very poor Color Rendering, usually 60 CRI or worse. Other newer sources like T5 or T8 Fluorescent, or LED typically will have better color rendering.
Here is an example. The top pic is 400W MH, the bottom LED. The MH I would estimate at 60 CRI or lower as they degrade with age, the LED is 70 CRI.
As a minimum, I recommend 70 CRI and a Color Temperature no higher than 4000K. Higher Color Temps will make blue hues "pop" more and lower Color Temps will enriched reds and the warmer colors. 4000K is a nice balance but personal preference does come into play.
For those considering LED, most will have a CRI of 70. You can get higher ratings but efficiencies go down dramatically. 70 CRI will allow you to differentiate colors in a wiring harness as an example. If you are picking out fabric in a clothing store, or viewing art in a museum, you might want a higher CRI product.
Also, higher Color Temps, above 4000K, will typically be found in cheaper products as the efficiencies go up and that is all some manufacturers care about. Fewer LED's = cheaper to make.
I will post the install pictures for this particular hangar in another thread as Color is only one factor that improved the "seeability", productivity, and eye strain by retrofitting Metal Halide to LED.
By the way, the paint color above is Cardinal Red from my '57 Chevy Cameo Carrier.