M33 from 27/10/2020 processed in PixInsight and Photoshop CS6

This is my first image stacked using PixInsight rather than DSS/Nebulosity – then DBE and LRGB combination (although this version only uses RGB as I hadn’t finished stacking luminence data at point on processing!). I then used Photoshop for curves, levels, a layer mask to bring out the galaxy a bit more, saturation, contrast, Gradient eXterminator and Astroflat Pro plug-ins and and a little bit of Hasta La Vista Green plug-in. The image below has now yet had noise removal or any further sharpening.


Focal points on Sky Watcher Equinox Pro 80mm with different Altair field flatteners

  1. During the changeover today from 1.0x to 0.6x Altair Lightwave reducer, I determined the focal points on the draw tube for future reference.


Focal point in Sky Watcher Equinox Pro 80mm OTA with Altair Lightwave 1.0x flattener and filter wheel and Altair 183M camera used for deep sky (as I used this week for photographing M31 and M33 – so this is the focal point that is correct for night sky for 1.0x Lightwave):

Focal point 1.0x Lightwave on roof our house from log cabin (note goes up from 46mm above on night sky to 56mm below due to roof being closer to telescope):

Focal point on our roof from log cabin with 0.6x Lightwave (44mm = means that the 0.6x field flattener requires extra 12mm of back focus over the 1.0x Lightwave and suggests focal point on night sky for 0.6x Lightwave field flattener should be around 46mm-12mm = 34mm on marking on draw tube):

Comparing 0.6x and 1.0x field flatteners

  1. Just arrived today is 0.6x Altair Lightwave field flattener – to replace my 1.0x version on my mono astrophotography setup – Altair 183M camera, filter wheel, field flattener and Sky Watcher Equinox Pro 80mm OTA on EQ6 mount.

I am making the change to increase my field of view and increase number of visible stars for Deep Sky Stacker, which keeps complaining that it can’t stack more than one file due to inability to detect enough stars.

The images below show the differences in field of view when I took photographs from bottom of my garden today of the solar panels on my roof.


0.6x field flattener:

1.0x field flattener:

Turn Back to Orion

Recently I’ve been struggling for ideas for visual observing. When there’s a clear night I keep going back to the same old targets, and whilst this is enjoyable, it doesn’t carry the same excitement of discovery. I think the root cause of this is not doing the leg work beforehand- I normally build target lists (often from other’s observing reports), but I’ve dropped out of that habit a bit of late.

A couple of days ago, whilst contemplating a tricky work problem, I picked up my old battered copy of “Turn Left at Orion” and started flicking through. In my first year of observing it was this book that really got me going, giving me target ideas and helping me to find my way around the sky. As I’ve become more proficient it has gradually fallen out of use, but flicking through it I found I’d done what everyone probably does and gone straight for the showpieces. There are a wealth of other targets along with nice little narratives.

So last night I worked my way with my 14” dob through pages 180-189 of my 4th edition. I used Sky Safari a little to help with the navigation (it makes it so much easier), but otherwise this is a session done Old Skool!

Mars: Alright- this wasn’t on the list, but you can’t ignore it, sitting there so prominently. I’ve become a bit spoiled in this apparition, having had quite a few outstanding views of it. Last night was a bit murky in comparison with the best of those, suggesting thin cloud, but I was still able to make out shading on the surface and the distinct solar cap. It’s been a wonderful target these last 6 weeks and I’ll miss it when it has receded.

Almach: Incredibly I’ve used this star to navigate many times, but never actually looked at it in the eyepiece. What a beauty! Very bright and to my eyes it looked blue and almost white with a hint of yellow!

59 Andromeda: Like two blue cats eyes, nicely separated and evenly matched.

56 Andromeda: This pair was a touch fainter and a less vivid colour, but more of a golden colour with a wider separation. It took a bit more finding, sat on the edge of a relatively sparse open cluster NGC752. With hindsight, I was sticking too closely to the script here and should probably have dropped in a wider eyepiece to enjoy the cluster more. The Baader 8-24 zoom I was using is very good for dropping in and out, but the narrow FOV at 24mm doesn’t give the best view of extended objects like this.

6 Trianguli: A much tighter pair at 3.7”, but quite easily separated at 8mm.

Lambda Arieta: A nice contrasting brightness, TLAO talks about contrasting colours but I can only see a hint of blue in the much fainter companion, whereas the primary seems completely white to me.

1 Arieta: Another tight pair at 2.9”, but quite easily separated at 8mm. Again, I was unable to make out a colour contrast.

Mesarthim: A more comfortable split and a much brighter double star, apparently even brightness (combined mag 3.86). According to TLAO the orientation barely changes, suggesting that we’re looking at the orbit edge on. I was curious about the name of this one so researched a but further- apparently it’s a corruption of nearby Sheraton; and as a star it appears in Chinese and Indian Mythology; in the latter as a doctor to the divine. It also gives its name to an Australian band who specialise in the Depressive Suicidal Black Metal genre. Who knew that was a thing? I’ll probably give it a miss…

M34: Turn the page and here was a more familiar object. To me it looks sort of like a flower stalk, set against the rich star field of the Milky Way. This time I did drop out to the 30mm- a really nice view.

The Double Cluster: Here’s an old friend, it even looks good in the finder. Sticking with the 30mm I was comfortably able to fit both sides in the same FOV. As well as the richness of the Star Field I love the different colours in this one. There are lots of tones of yellow and blue, and then a few deep red ones really stand out. Found myself in disagreement with TLAO here- it claims this is much prettier in a smaller telescope (a 4/4 frac view, but only a 2/4 dob view), but I find the view in my Dob for this one glorious- the number and concentration of the stars make this one of my favourite sights. On the other hand- I do like the way TLAO descriptions lapse into the whimsical- “the view from a planet in one of the clusters would be spectacular: perhaps a hundred stars in the home cluster would be far brighter than the brightest star in Earth’s sky, while the other cluster would be far more impressive than any open cluster in our sky”. Now there’s something for your dreams.

The Pleiades: Having the 30mm in the scope and talk of spectacular open clusters made me take a detour to the Pleiades. Perhaps natives of the Double Cluster have a better view, but this one does me just fine. The electric blue colour and patches of nebulosity still visible even with the strongly illuminated moon. Yum!

Back to TLAO…

Iota Cassiopeia: This again is a familiar target; I find it a good test of conditions, especially when the Double Double is dropping low. I quite enjoy pulling it up at 24mm, when it looks elongated but single, and then zooming. At 20mm it’s already a double, but I’m at 10mm before the third companion starts to appear. By 8mm it’s a clear separation. Sometimes I can see hints of colour, but tonight they all look white.

Struve 163: Another triple, but much greater separation. The A and B stars were showing fantastic colour- deep blue and orange, although the third was much fainter. This was another discovery for me, a lovely sight, I need to make this a regular stop!

Eta Cassiopeia: Another pair of contrasting brightness, I found this quite a straightforward separation. TLAO claims sharply contrasting colours, but I couldn’t get this- just a hint of orange in the secondary for me.

Burnham One: I struggled to find this one a little, and didn’t manage to split the A and B pair (1.1”- which is usually just in range for the dob). I should have tried a mask, but was more excited that the transparency had improved a bit and some clouds to the south were dampening the moonlight to the extent that I could see the PacMan nebula- something I’ve never managed from home before!

Sigma Cassiopeia: This, at 3.2” was an easier split- the clouds were coming closer now…

Struve 3053: Last view of the night and another new one for me. I had to be quick with the star hopping to beat the oncoming clouds, but got there just in time- and very glad I did. Quite startling orange and blue- a really lovely view.

The encroaching clouds ended it there, but really enjoyable to get the buzz of discovery back. I would happily have turned the page for a tour of Cassiopeia’s open clusters, but that’s going to have to wait until the next time!

Pelican Nebula – narrowband

My second ever photo in narrowband – HA-OIII-SII.

On this occasion, I decided to photograph the Pelican Nebula……I used plate solving to get into the nebula but did not realise that this meant I was right in the middle of it and hence my image below (which is based around the star HD198896) does not show much of the well known edge of the nebula – still, it is a riot of colour!

SII – Red
Ha – Green
OIII – Blue

  • Sky Watcher Equinox Pro 80mm OTA
  • EQ6
  • Altair Astro 183M camera
  • Baader 7-8.5nm narrowband filter
  • PixInsight/Photoshop CS6