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?

Observing Log 9/1/2021

Orion UK 10 inch Dobsonian

Explore Scientific 9mm 100 degree AFOV eyepiece



Wow! I have just had my best ever view of M36, 37 and 38. Never expected that tonight. Using ten inch Dobo with Explore Scientific 9mm 100 degree FOV eyepiece, each cluster fills the field of view of the eyepiece. The views of M36 and M38 are extremely bright with that diamonds on velvet appearance that makes the Double Cluster in Perseus through a 10 inch Dobsonian scope such a wonderful view – it is just that I have never seen it before with these three open clusters, which often disappoint,  but not tonight! M36 is entirely different, with loads of fainter white stars, also filling the field from end to end. What a comparison! I guess this must be related to how high Auriga is riding tonight, at about 75 degrees for these clusters. Not the clearest of nights, but not too bad either – 7/10 on my personal “visibility of Orion’s sword” scale (I resort to this because the local seeing conditions are almost always poor so it is a question of how poor they are tonight….) There is minimal scintillation and, at this elevation, the constellation is above most of the light pollution.

Looking at Pleiades, can see that the sky has lot of moisture with halo around the brightest stars.

I have been photographing the Tadpoles with my imaging rig, but Orion now cleared the trees. At the RAG astrophotography SIG last night, Rob Leonard suggested this months target should be something in Orion, so I have now moved over to Orion to photograph the Horsehead and Flame Nebula. Only once have ever photographed those in colour and it is an awful picture. Since then I’ve taken a half-decent black and white photo – hopefully, if the clouds hold off, I can add a reasonable colour photo to that tonight…….although of course today’s reasonable becomes tomorrow’s awful as our standards improve with experience (I also very happy with my previous photo when I took it!)

I am quite excited about tonight. I must go for my Covid vaccine tomorrow at 9am so sadly can’t keep going so in a minute I am going to put the kit away. However I have managed 2 hours straight in Horsehead. This is first time that I have ever been able to keep imaging one object for that long on single night, either because of cloud or because the object I am imaging goes behind trees in my garden. And its a great object too – the Horsehead and Flame plus my stars look round(!) So hopefully I can produce something decent.

The Tadpoles Nebula

I caught this one on Christmas Eve. We had a lovely clear night, and although it was very much family time I did manage to sneak out and set the scope running. It was pretty clear nearly all night, so I was able to gather data for all the channels in one night- a rarity in UK narrowband imaging. Details are:

Capture details are:

RGB (for the stars) – 10 mins/channel – 20x 30 seconds, Ha – 90x 2mins, Oiii and Sii – 75x 2mins.

130pds on HEQ5 with ASI1600mm at Gain 250.

I’m normally indecisive about the best presentation, but in this instance the Hubble version was definitely the one to go with, as it really highlights the tadpoles. I’ve also included a Starnet version- it definitely adds some noise, but you can see the faint bits of the nebula much better.

I was curious about the Tadpoles- apparently they’re similar to the Pillars of Creation in the Eagle Nebula- dust and gas left over from the formation of the nearby star cluster NGC1893, and the nursery for future star creation. They point away from the cluster because of stellar winds and radiation pressure from it.