Best solar power efficiency watch face.

The solar cell is *above* the display, in the glass, and anyway only harvests a small part of the energy. Most is collected by the conventional tech *around* the LCD. But theoretically, you could assume that the reflector *behind* a *clear* display reflects a little bit more light back to the 'power glass'.

Summing it up, though, black or white should barely make a difference, as apart from the reasoning above it's a memory-in-pixel LCD-display.

Seconds vs no seconds is far more important. And now ask Garmin why they don't make disabling the seconds on all watchfaces apart from on wrist turn or light button press an option, or even make the seconds an additional small data field. The Tactical apparently has that latter option on at least one watchface, going by the pictures. But suggesting anything like this is futile. I realise there are watchfaces without seconds, but if you don't want those, you're out of luck.

The solar panel "around" the display is supposed to give 100% power (when available) The power glass, I think,. is only rated for 10%.  The question was if a black screen would prevent more light going into the power glass.  Really not an issue, just asking.

Thank you for clarifying. I apologize for missing the bus on your initial question. When your Instinct Solar is 'off' - you may receive a slight benefit when solar charging but only due to not having any battery drain thanks to your watch being off. It is not a cause and effect of the display being light or dark.

Thank you.  I tried to have a limited amount of light exposure under both scenarios and could not make any difference in regards to which one is better, power wise. I like the black screen better because it blends more with the solar panel.