What is Reverse GND?
Normal GND graduated effect is from dark at the top to light in the middle, leaving the lower part clear. GND Filter is always being used to balance out the exposure difference of the sky and foreground. However, the sun will be in the middle of the photograph during sunrise and sunset. Reverse GND is needed at this moment as the middle part will be the darkest to avoid overexposure around the sun.
Q: Reverse GND only comes with 0.9 density?
A: Same as other GND, Reverse GND also comes with different densities. We usually use Reverse GND when taking sunrise or sunset photos, 0.9 can get you there!