Originally Posted by Nirrity
so, is there any consensus in what color temperature is better overall: 3000K or 4200K? Also, does higher CRI have any beneficial effects over lower 80 CRI?
looking at this chart (if it's accurate) i'd say 4200 is better since it has more spikey red around 650 nm, less pronounced yellow/orange and more blue, while 3000K has huge spike around 680, more orange and less blue. i may be mistaken but 680 isn't that good at all, is it? seems closer to IR than usable light.
Using CRI in horticulture industry is a mistake. CRI is a scale of 0-100, it is used to describe how accurate a light source renders color of an object.The higher the CRI, the better the color rendering ability. Plants don't need high CRI light to render their color.
The most important criteria is SPD, then the relative strength of different wavelength lights, the last is PPF.
Philips 3000K and 4000K bulbs are full spectrum, both can be used for veg and flower. If you have a 400W dimming CMH ballast, better to use 4000K bulb.