> For winter I got a standing tanning machine. Which I use 2-4x a week for 1 minute per use. I calculated this was equivalent to 5-15 minutes outside, depending on time, but engages the entirety of the bodies largest organ.

Excellent idea. In my temperate climate, I use the outdoor method, with one further tweak: Cover the head and arms, which get too much inadvertent exposure anyway during daily activity.

Sounds good, I'll schedule my time to wander the neighborhood nude, except for towels around my head and arms.