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Observation by Richard Miles: Widefield camera flatfield from 2020 Jul...

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Richard Miles


Richard Miles


2020 Jul 16 - 20:00


2020 Jul 18 - 14:14

  • Canon 300mm f/2.8 lens
  • Starlight Xpress H18 (KAF8300) CCD
  • V filter

4 sec


Golden Hill Observatory (J77)

Target name

Dusk sky


Widefield camera flatfield from 2020 July 16

About this image

The camera has a mechanical shutter that takes about 1/40 sec to open fully so to avoid a gradient in the response I had to use a relatively long (4 sec) exposure and stacked 42 such frames dark-subtracted using 20 dark frames. Stars are registered and these are edited out by cut and pasting small sections using Salsa J software.

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Nick James
Nick James, 2020 Jul 18 - 23:39 UTC

I've seen worse...

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