A local carpentry workshop made us beautiful larch shutters… however, they were untreated/raw. We primed them ourselves and painted them with our chosen color (RAL 7033 cement gray) using a spray gun. Today we installed them.. tada..
With online tools like these, you can get a first impression. It definitely makes sense to order sample mixes of your preferred colors and test them on a roughly 1sqm (11 sqft) painted area using the actual material, experimenting under different lighting conditions on site. This, of course, if the "right" color is worth the effort to you.