No. For the flower cycle "dark" means total pitch black, not even a crack, can't-see-your-hand-in-front-of-your-face kinda dark.
...well... sort of... you can use what's commonly called a "graden safe" light. It is a low-wattage green bulb that will allow you to work around your plants in the dark cycle. You can find them at specialty nurseries (and maybe at Home Depot or something)
Thats for outdoors. For indoor try to keep pitch black. If the light in the room does not exceed the brightness of the full moon (almost impossible to determine with the naked eye) they should be fine. Get a green light if you want to see at night. I just stay out of my grow room during flowering night time. Vegging night time does not matter.
True, the moon and stars do indeed com out. But a couple of points: - First, people are always wanting to know how much light during the dark period they can get away with. The best answer is none, except maybe for the special green light Up4 and SmknVTEC refer to. The key point is that you have 12 hours of light to tend to your plants, leave 'em alone for the other 12 because every time you let light in you change the conditions and can confuse them. - Second, outdoor wild plants have a lot of variation in their genetics and are very hardy. Specialty strains are another story. Nature does not cross and back-cross and cube the genetics until the plants can become more high-strung than a race horse. That kind of selective breeding can lead to some big-ass colas with all the qualities we like but can leave them finicky about other things, like turning hermie. One peep of light may not do a thing. But then there's always someone who wants to know: well, what about two peeps? Three? 12 of dark is what works.