Monthly Archives: May 2020

Added Colour to NGC 4565

Here is the first round of adding colour data to the previous NGC 4565 image. Colour doesn’t come through my light-polluted sky very well – I could use a lot more time on the colour channels, but will have to wait until next year because there isn’t much time now between darkness and the target setting.


Exposure Luminance: 90 minutes (18 x 5 minutes)
Colour: 20 minutes (10 x 2) of each of Red, Green, Blue
Camera QSI583wsg, with Astrodon LRGB filters, running at -15°C
Image scale 0.69 arceconds/pixel (luminance), 1.38 (colour)
Telescope AT8RC
Mount Paramount MX+
Guiding Autoguided with Starlight XPress Lodestar
Processing 32 dark frames per sequence
32 flat frames per filter
Sigma-clip mean combination on the darks and flats
Sum-combination on the light frames


NGC 4565

Finally a couple of beautifully clear nights, not cold, and not busy with other things.  I started data gathering for NGC 4565.  This is 90 minutes of Luminance only (18 5-minute frames).  It’s still a bit noisy in my poor quality skies, so I plan to do another hour or so next clear night.  Haven’t gathered any colour yet.

NGC 4565