Flat Panel

Even screen light for flat frames. Set the level, trim the colour so the one-shot colour sensor sees similar signal in R, G and B, then start the panel over the telescope.

R
0
G
0
B
0

Level

0 is black, 255 is full white
/ 255

Colour balance

100% leaves a channel alone

Pull down the channel that is too strong. Each channel is the level multiplied by its trim.

100.0%
100.0%
100.0%
Set trims from a test flat

Shoot one test flat at the current settings. Subtract the bias, then measure the mean value of each colour channel in your stacking or capture software (average the two greens). Enter the three means below and the trims are corrected for the screen's gamma of about 2.2. Check again with a second test flat.

Panel options

Before you shoot
  • Turn off auto-brightness, night light, blue-light filters and forced dark mode, then set the system brightness once and leave it.
  • Use this level control for exposure matching. Very low levels have few steps, so the output values above move in jumps. Raise the level and shorten the exposure instead.
  • Put a layer of white cloth or paper between the screen and the telescope, and keep the screen distance and angle the same for every flat set.
  • Keep the same focus, camera angle and optical train as your lights.

Double-tap the panel to return here