You need white or at least light color paint on as much surface (including joists) as possible ,otherwise it takes 4x as many lights. As for lamp color, you should read up on bulb "temperature" aka "Kelvin". Above 4k and below 3k doesn't bring out true colors. I reccomend Daylight for good light that shows true colors. Four fixtures with two 4 foot tubes each ( 8 tubes) should light all corners without shadows if most of ceiling and walls are painted. If accurate color is important don't hesitate to mix Kelvins.

Thanks. Walls are white. Rafters are gray. Painted by previous owner. But the effort to paint rafters white is too great because of all the mechanicals and the shop itself. So will need to add extra lights.

Recommended foot candle levels

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