Yet there they are, those lavender or purple discs, softly blending into green, or blue-green hues outside the halo. Observe and jot down the names of the colors on a simple pencil sketch and try to paint the effect by broad daylight. Let me admit at once that this isn't easy. You'll have to try and try again, with darker, and lighter tones, softer, and bolder contrasts, until you achieve the appearance of glowing lights. The next problem is to render people, cars, walls, and windows by these lights.
Basic colors remain recognizable by artificial light, but the differences are great.
Look at each piece by candle flame, by a small, yellowish electric bulb, by a white bulb, by white fluorescent light, by the light of a blue bulb, a red bulb, an orange-colored bulb, a green bulb. Almost any household can easily provide these different lights, or at least some of them. You can buy colored bulbs and insert them in the same socket, one after the other. Try to determine each color, each shade by each of these lights. But this is wrath-risking.