A Tipsy Dither

At last AP group meeting Neil suggested sharing bloopers, and I was thinking afterwards that it was a good idea- so here’s my submission…

Sods law dictated that the only clear night in weeks should coincide with a pre-arranged zoom drinks and quiz night with some local dads. I thought that at least I could get some imaging done whilst it was on. Trouble is, to avoid walking noise, I have to manually dither the mount.

Three rounds in, before my turn to be question master, I suggested we have a ten minute break and quickly hared into the garden. Unfortunately it’s quite a delicate procedure, involving a tiny couple of degrees on the slo-mo knob. I completely botched it and had to do a hasty re-alignment. Just about got it done and ran back in thinking ‘Phew- got away with that’.

No, I didn’t.

See below: imaging restarted with completely different framing and polar alignment knocked out, leaving the mount slewing drunkenly off track. A bit like myself!

Horsehead and Flame Nebula Hydrogen Alpha from 22/1/2021 and first attempt at combining that data with LRGB image same field from 9/1/2021

On evening 21/1/2021, I collected 100 minutes of data on the Horsehead and Flame Nebulae – first time even using just one narrowband image on an object in an evening – this was on advice of Ken Critchon – and it was excellent advice – as I obtained te image below! Minimal processing – stacked using weighted batch pre-processing script in PixInsight and Photoshop curves to make data visible.

Then I tried to combine this image with my previous LRGB one from 9/1/2021 in Photoshop – a less successful effort! Don’t really know how to do that.


Re-processing my Horsehead and Flame Nebula from 9/1/2021

I have further processed this data to see how much detail I could bring out.

The issue is that really bright star – when I used curves to bring out detail then the star became extremely bright and adversely effected the rest of the image. So, I addressed it by creating 2 copies of image, masking the star in one and other bright stars in image. I then increased curves on that image to bring out detail and the mask stopped star blowing out.


Horsehead Nebula data from 9/1/2021

Thanks to RAG members who have offered to have a go at processing my Horsehead and Flame data to see what you can make of it.

File can be downloaded by clicking on link below – comes with calibration data – ZIP file – WARNING! The file is 10GB in size!

Horsehead and Flame Nebula in Orion, light frames & calibration files, Altair Astro 183M/Sky Watcher Equinox 80+1.0x FF/LRGB 9/01/2021 (ZIP file, 10 GB)



Horsehead and Flame Nebulae from last night

My photo from last night:

  • 3 hours of data.
  • 80mm Sky Watcher Equinox Pro telescope.
  • Sky Watcher EQ6 mount.
  • Mono camera Altair Astro 183M – Baader LRGB 7-8.5nm filters.
  • Taken in Lichfield, UK.
  • Sky had some transparency issues & below zero temperature outside.
  • Telescope set up on garden.
  • Processed in PixInsight and Photoshop CS6 with GradientXterminator filter and Astroflat Pro filters; and Topaz AI Noise and AI Sharpen filters.


Which version of following two do you prefer?