Contains: NGC 1931, IC 417, The star φAur
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IC 417 & NGC 1931 Spider & the Fly Nebulae

Technical card

Resolution: 3410x2868

Dates: Feb. 28, 2016

Frames: 32x900"

Integration: 8.0 hours

Avg. Moon age: 19.93 days

Avg. Moon phase: 72.74% job: 1799384

RA center: 82.289 degrees

DEC center: 34.496 degrees

Pixel scale: 1.436 arcsec/pixel

Orientation: 359.992 degrees

Field radius: 0.889 degrees

Locations: The Hills Observatory, Manchester, United Kingdom


I was experimenting with different bins with this image. The conclusion for Ha at least, don't bother stick to bin 1x1. With other bins the resolution is quite poor especially bin 4x4.

But the result was ok in the end. This is basically a Ha image, but I took 10 x 1min subs for R G & B and added those in with Ha to get coloured stars. The aim of this image was to go deep and I think I managed that with lots of faint nebula.

The actual sub exposures were (taken 20151224 to 20160228) :
900s x 8 bin1
1200s x 13 bin1
900s x 4 bin4
900s x 3 bin2

60s x 10 of each bin1

Update: As my processing has improved over the years I thought I would re-work this image as it was one I was not happy with. This is a Ha image with added RGB stars, but not done very well. So I went back to the calibration and completely re-processed this image without adding any more data. The result is more detailed, stars that are no longer bloated and the right colours.



Mike Oates



Completely re-processed

Sky plot

Sky plot


IC 417 & NGC 1931 Spider & the Fly Nebulae, 


        Mike Oates