Banding

The background at full size, stretched hard. The lines run straight across or straight down the sensor, never at an angle.

1. 01

   Sensor pattern noise, undithered

   The sensor's own pattern noise lands on the same pixels in every undithered frame, so stacking keeps it.

   FixDither between frames so the pattern lands somewhere different each time.

   Session Checklist
2. 02

   Flat panel PWM flicker

   An LED panel's PWM dimming beating against very short flat exposures makes banding that looks like a sensor defect. Bands that appear only after flats are applied point here.

   FixDim the panel so flat exposures are long enough to average out the flicker.

   Session Checklist
3. 03

   Power supply noise

   Electrical noise on the camera's supply can show up as stripes.

   FixRun the camera from a different supply, a battery if you have one, and compare a dark frame from each.

• Walking noise

  Walking noise is diagonal, at the angle of the drift. Banding follows the sensor's rows or columns.

One frame shows the stripes. Whether the sensor, the flats or the power supply makes them needs a raw sub, a flat and a dark frame side by side.

No stripes under a hard stretch in a stack of dithered subs, calibrated with flats exposed long enough to beat the flicker.

No outside source is cited here. The signature, the causes and their order are the atlas’s own, from imaging experience. The order is a judgment of likelihood; no measured frequency is behind it.