Sky Watcher HEQ5 Pro Mount

Forum threads on 45 degree offset error on HEQ5 mount during alignment

I have found these two forum threads on the 45 degree offset error during alignment of the HEQ5 Pro mount, similar to my experience with my own mount over the last couple weeks. Not sure whether they give me a solution though!

Andy

Forum threads on warning 45 degree offset error on HEQ5 accessed 181019 (PDF file – this file there are two forum threads – scroll through the pages to see the two threads)

mobile base for EQ6/HEQ5 completed

At last! My mobile base for my EQ6 is completed. Someone will note slightly extended legs and wonder why…..answer is that base is designed to take either EQ6 as is currently on it or HEQ5- and the tripod on HEQ5 (same as EQ5 tripod but different from EQ6 tripod) has long legs and wider spread than EQ6 tripod.

Andy

Filtering the Crescent

Over the last couple of weeks I’ve been imaging the Crescent using different focal lengths and filters

Widefield 135mm

I was working out that this is the fourth time I’ve been imaging in or around the Sadr nebula. On this occasion it was because I’d already started on the data for 900mm shots of the Crescent and I thought it’d be nice to have a wider shot of the general area, putting it into context. I was inspired by Neil’s recent results with his Triband filter to see if the same (or similar) technology in a clip filter would help with wide frame nebula images and acquired a Skytech Quadband (that transmits 2 35nm bands around Ha, Hb, Oiii and Sii – hence the name) . I must say I’m quite impressed- I got this from a sequence of 20x 150 second captures on Sunday night under a 99% moon using the Russian made 135mm vintage lens I’ve posted about previously. Normally I’d only attempt proper Narrowband under these sorts of conditions, but I thought it coped pretty well under the strong moonlight. The only slight concern is the halo around Sadr itself.

The photo picks out how prominent the Crescent is (below and to the right in this picture), but also shows how “busy” this bit of sky is- the Butterfly nebula pops out, with its prominent dark lane, but the fainter cloud that it’s a part of extends beyond the frame. There are also clusters aplenty- my favourite is M29 – the Space Invader cluster just below and to the left of the centre. Probably my eighties upbringing…

Hydrogen Alpha

These are taken using a Baader 7nm Ha Filter on a modded Canon 550d in a Skywatcher 200p- altogether I got 12 10 minute subs before clouds stopped me. I think this is the best of the shots for showing the structure of the object and the shockwaves that form its shape; the monochrome also highlights the cloud of the larger surrounding nebula.

Oiii

This came from the same setup and 10 more subs, this time with an 8.5nm Oiii filter, and a 99% moon on 13th October. The only Oiii visible in this shot is around the nebula itself. The signal was quite a bit weaker than the Ha; this picture was created by discarding the Red Channel and then combining equally the Blue and Green using Pixelmath in Pixinsight.

Bi-Colour

Finally, it’s all brought together using the same process- this time feeding the Hydrogen into the Red channel and the Oxygen into the Blue and Green. I spent quite a bit of time playing with this one. Just feeding the data in, the red was total dominant and I progressively multiplied the Blue and Green until it was more prominent (the eventual multiplier used was 2). I also experimented with trying to change the balance to bring a little more colour into it, but that also artificially unbalanced the star colour so I decided to leave it even, which makes the Oxygen mostly white when combining with the Hydrogen.

I’ve really enjoyed taking these different views of the same object and learning about it. The nebula itself, 5,000 light years away, is 25 light years across and is caused by fast stellar winds erupting from the Wolf-Rayet star visible at the centre of the nebula. It’s thought the star will imminently (in astronomical terms) become a supernova.

Sky Watcher Equinox Pro 80mm OTA + Tele Vue TRF-2008 field flattener + QHY10 camera & William Optics 66mm OTQ with T7C guide camera + TS OAG/flip mirror on HEQ5 Pro & focus points on both scopes with these cameras 20/9/2019

Sky Watcher Equinox Pro 80mm OTA + Tele Vue TRF-2008 field flattener + QHY10 camera & William Optics 66mm OTQ with T7C guide camera + TS OAG/flip mirror on HEQ5 Pro & focus points on both scopes with these cameras 20/9/2019:

     

Cygnus Wall – Bi Colour

Over the full moon period we’ve had a couple of clear nights and I’ve taken the chance to get some pictures of the Cygnus Wall in Ha and Oiii. Back in February/March I had an attempt to do this on the Cone nebula but the results were not brilliant (suspect user error is to blame as usual). Here are my results from the same technique on the Cygnus Wall that have come out much better. Possibly part of it is understanding that the Oiii data is considerably weaker than the Hydrogen data and compensating a bit for that.

Anyway- below are the images- they’re 1 hr 20 of Oiii (I took 3 hours but most of them had to be thrown away due to moonlight and cloud) and 2 hr 40 of Ha (only had to reject 2 of these) plus the usual calibration frames.

Firstly – Ha:

Then Oiii (yes, I’m still not great at aiming the camera in the same place on two successive nights, but it’s tricky when you can’t see what it’s taking a picture of!)

Finally- the combination made from feeding the Ha into the Red Channel and the Oiii into the Blue and Green:

 

 

 

Weekend Opportunism

Between a busy work week, family commitments and some so-so forecasts it wasn’t looking good for astronomy this weekend, but it turned out pretty well.

Friday Night:
Imaging-
Didn’t get out until about 10:30 but tried to make up for lost time by setting both the main scope going and trying out my 50mm lens on the Star Adventurer. I had high hopes for the 50mm lens- it’s another oldie (I’ve had it about 15 years), but online quite a few people are getting great results with them. Well- I’m not in that club (yet). The diaphragm only has five blades and although I stopped it down to f2.8 (it’ll open up to f1.8) all of my stars are pentagons and DSS is refusing to recognise them as stars- so no results from that. Fortunately, the main rig saved the day: I went for NGC6946 – The Fireworks Galaxy with my 200p. Throughout the session low clouds were interrupting the view, and around half the subs were lost, but the ones I did hang onto gave the result below. Over the summer I’ve picked up a second hand Canon 550d that has been home modified with a Peltier cooler and put into a metal case- it’s not pretty, but it seems to be effective. This is 13×4 minute subs and throughout this session it held the temperature down to around 7-8 degrees which I’m pleased with (a couple of degrees below ambient, my 600d usually runs about 10 degrees above ambient and is consequently much noisier). The target itself is quite a bit smaller than I’d anticipated- this is a crop of about 20% of the frame. Despite the small size- I think this is a lovely target- both for its colours and the asymmetry in the arms.

Observing-

Whilst the cameras were doing their stuff I had the Dob out on the following objects:

The Double-Double- I used Vega to get the finders lined up then dropped down to Epsilon Lyra to check out the seeing. It was a straightforward split, but I could see that the transparency was not great.

M13 & M92 – I often start with these and never get tired of them. In Binoviewers at about 260x they fill the field of view and appear 3 dimensional. For me these are the only types of objects that actually look better in the eyepiece than in a photo; I love the difference in their appearance- M13’s great with lots of features, but a bit of a mess with arms everywhere, whereas M92 is compact and very neat. Just wonderful.

The Veil – I was reading a thread on SGL recently which referenced a Sky and Telescope article on The Veil (https://www.skyandtelescope.com/astronomy-blogs/explore-night-bob-king/explore-veil-nebula/) . Using this as a guide, and with an Oiii filter a 30mm eyepiece (55x) and a coat over my head I managed to explore just about the whole thing. I’m a bit prone to hopping from object to object whilst observing, so it was great to really take my time in the tranquillity of the small hours and drink it all in with nothing but the odd clunk of a shutter release and that American woman with the nice voice who commentates on APT saying “Dithering started…” softly in the background. Ahhh… a very nice dither contemplating the remnants of a supernova.

I was on the Veil for over half an hour and loved every minute of it, but decided with to move on with the Oiii filter and go check out M27. This is normally not a problem, but by this point the transparency had deteriorated so much I was unable to hop to it. Altair was the only nearby star that was naked eye visible and despite several attempts I just couldn’t find the stars in the finder to hop up to M27. Reluctant to retire I switched up to the North East to check out M31 as the skies looked better in that direction. Before I could get to it a bank of cloud blotted it out. Time for bed…

Saturday:

I managed to pop out briefly whilst doing other things on Saturday evening and set the imaging rig running on M13. This was a bit of an experiment: I’ve imaged M13 before, but with my guide camera on a smaller scope using the short exposure method. Whilst I was quite pleased with those outcomes (see https://roslistonastronomy.uk/catching-up-on-images) , I wanted to see how it would look with more integration time and a DSLR chip. This is 22x 4 min subs plus calibration frames and I am really pleased with it. As a bonus for the last half-hour it was running I sat outside with Sam observing the sky primarily with Mark 1 eyeballs. After a while we were both able to pick out the Milky Way running up through Cassiopeia and Cygnus despite the local light pollution. A real pleasure!

Painting/staining of new HEQ5/EQ6 mobile base with Cuprinol now completed

Two layers of Cuprinol later (left over from my wife’s fence painting project earlier in the year), the new mobile wooden HEQ5/EQ6 will be ready for vanishing with yacht varnish once it dries – and with high humidity levels at present and low temperatures I think it might take a few days before it properly dries out from the water based Cuprinol. That’s the price you pay for using left over stuff!

Andy

Making base for HEQ5/EQ6 Andy & Alan+Angella from RAG 3/9/2019

Now that I am doing astrophotography, it is important that I create stable, mobile base to allow me to roll the mount in and out of the log cabin. The more that can remain set-up between sessions, the easier it will be to image – especially important in the UK as weather liable to deteriorate again quickly.

Angella & Alan came around today and helped me build a fantastic base – thanks Angella & Alan!

Andy