Captain Scarlet

Sorry it’s my new frac 🤷‍♂️

No I think Gerry you should get rid of the SV, then there’ll be no use for such a short-FL eyepiece as the 2.4 Vixen HR. In which case as a special favour I’ll take it off you. I’ll send you my address 😉

7 minutes ago, Froeng said:

Thanks for the enjoyable report Magnus!

May I ask what focal length your Newtonian is?

Thanks

Frank

The mirror is Orion Optics 1590mm FL, which goes up to around 1830mm with the Paracorr2, ie ends up as f/6.2.

Centre spot accuracy  seems to be a largely unacknowledged problem with Newtonians. Both my newish expensive 1/10wave mirrors had misplaced spots, one grossly so. I removed and replaced them myself.

As you’ll know, Newtonian collimation amounts to the alignment and coincidence of the two optical axes, and that spot, its shadow and/or reflections is used to determine those axes. If the spot is wrong, miscollimation is guaranteed.

A marker dot will certainly help, but might be difficult to see under certain circumstances, and if you’re using a barlow method, might not get reflected as a shadow.

The outline of the edge of the mirror might be ok to use to roughly align the eyepiece axis (to the primary centre) if you’re using, say, a Concenter which has a central hole and concentric circles etched into its glass face: you’d use that hole to indicate the centre of the primary. But that won’t help aligning the primary back to the eyepiece axis, you really need a mark for that.

Cheers, Magnus

An unexpected session for me tonight with the big new refractor. I set it out early to see Jupiter Venus and the Moon but the seeing was terrible. I left it all out anyway on the off-chance. Good thing I did. I went back out around 11pm and ‘twas unexpectedly clear. So I cherry-picked from my SGL-gleaned ongoing list of targets.

32 Orionis was a split, my first ever attempt. It was coming and going with micro-seeing. I fancied they were slightly different colours, one yellow/whiter, the other bluer? Possibly atmospheric-induced though. 52 Orionis was a no-go despite two tries, getting worse as Orion sank. Tegmine zeta Cancri was also split, the tight pair separating beautifully from moment to moment. Wasat (delta Geminorum) was like a high-mag Polaris, lovely. Polaris itself of course. Session ended when trying to select for local carbon stars my Nexus crashed, I called it a night.

Cheers, Magnus

Pointing at a very wobbly Jupiter before being engulfed by a cloud-bank:

Notwithstanding my recent acquisition of a 5.5” refractor and my frustrations trying and failing to get the latest firmware on my Nexus DSC to work with my AZ-EQ6, with clear sky in prospect I decided nonetheless yesterday to use my 300mm Orion/Helmerichs Newt and the Nexus to try to take advantage of the last properly dark Moon-down night this Lunar cycle. I am worried that the whole Orion season will pass me by this year without a proper 12” session on it. The new frac can wait until the Moon is up.

As it happened, I still didn’t get my Orion session in, for a couple of reasons, but I did have a mammoth tour of 20-30 mostly faint galaxies in Ursa Major and Coma Berenices, almost all of them new sightings, for me.

Early evening, whilst still light around 6pm I hoiked all my stuff out around the back to the one place reasonably sheltered from the howling gusting NNE wind. Wind which was supposed to become more acceptable later on, but at that time it was strong, and cold. My new wheelbarrow makes the equipment-trip around the house so much easier though. 2-3 trips instead of 6-7: the wheelbarrow can take the 3x5kg counterweights, AZ-EQ6 head, 255mm Rings, battery, collimation kit, bags of cables and knick-knacks all in one go. Nice when setting up, GODSEND when packing away at 0130.

I couldn’t help noticing the 8.5% Moon sitting beautifully between Jupiter and Venus, so I had to quickly set up my DSLR and take the picture:

That sheltered place meant I only had a view from East to South, and a bit higher up to the West. I had wanted to spend some time in Orion early on, but by the time I’d sorted out various problems, Orion was behind a hedge. I fear a proper full-darkness Orion session might have passed me by this year. Perhaps next Lunar cycle might provide one.

As I was having dinner, after setting up, I noticed a huge black mass approaching from the North. Wind suddenly picked right up and rain battered the windows. I pretended it wasn’t happening hoping it would pass quickly and that the mount and scope were sheltered enough to survive a short squall. They did: by the time I got out again everything was dry and good.

Anyway, the problems: mount alignment was a nightmare, but I was half-expecting it. The latest firmware versions for the Nexus DSC do not play well with the GOTO on the AZ-EQ6. I thought I finally had it working during testing during the afternoon, but for insurance I’d loaded a previous firmware version on a USB stick and stuck that in my pocket. In the event during the session, after about ten attempts to get the mount to either align or work properly, I downgraded the firmware “in the field”. After that it behaved perfectly, but Orion had gone. Oh well, Leo, Coma B and Ursa Major would have to suffice instead.

The night turned into a feast of galaxies. I was using the Nexus “Tour” function to start with an object I knew in a given area, and it returns all objects within selected catalogues within a certain angular distance. I made it 7 degrees radius. I’ve related what I saw more as a list rather than a narrative – there were just too many!

Leo Triplet: M65, M66, NGC 3628 – of course these need no introduction. At 183x I had to look at them individually.

In Ursa Major (I had no idea there were so many bright galaxies in this region):
M109 – not appreciably in a different brightness league from many of those that follow, but somehow it gets a Messier label whereas the others do not. Dimmer than I was expecting.

And others in the so-called Ursa Major M109 Group: NGC 4102 mag 11.2; NGC 3982 mag 12.0 pure face-on therefore dimmer than mag 12 would suggest; NGC 3998 mag 12 lenticular; NGC 4026 mag 10.7 edge-on Lenticular; NGC 4088 mag 11 spiral; NGC 3756 mag 12 spiral which Wikipedia says does not exist, but also lists it in the M109 group; NGC 3922/24 two names for the same galaxy apparently, mag 13.5; NGC 3893 mag 10 face-on spiral. I stopped at this point as I was on the top step of my 2-step ladder, and only selecting targets that allowed for lower altitude!

I wanted to have a more systematic look down the Markarian Chain of galaxies in Coma Berenices than the last time I was able, 2-3 years ago. The Nexus unit allowed me to do this perfectly. I started at M84, a bright giant mag 9 lenticular, and first of all panned East noticing lots of brightish blobs all over the place. Returning to M84, I used the Nexus Tour feature again. I noted NGC 4387, a mag 10 lenticular nearby; NGC 4388 a mag 11 nearly edge-on spiral; M86, the bright mag 9 elliptical, NGC 4425, a mag 11.8 lenticular; NGCs 4435 & 4438, a pair known as “The Eyes” a striking even pair at mag 10. Aka Arp 120 (my first Arp!); NGC 4431, a 12.9 lenticular, near to NGC 4440, also seen, mag 12.7; I moved along a bit to M88, a mag 9.6 spiral, magnificent in proper photos. I finished off the region with M91, a mag 10 face-on (therefore quite dim to eye) spiral. Next time I’ll do all the local Messiers (no shortage) from M85 down to M60, around 14 Messier galaxies in all!

All the above I observed using my Delos 10, giving me 183x. I must say that the GOTO, after  my troubles, was spot on each time. Very impressive at such magnification.

I fancied a wider-field view by now, so I switched to the Nagler 31 - 59x and 1.4 degree field - and panned across the local area without referring. Just a lovely view, galaxies all over the place.

I went back to Ursa Major and had a look at M51. Lots of detail, spiral just tantalizingly visible with direct vision, a sight of which I never tire. I went to M101 which as expected was easily noticed and much brighter than when I collect it in binoculars. I would have gone for M81/82 as well, but they were almost at zenith, and even with my steps I wouldn’t quite have reached the eyepiece! I need better steps.

I could see by now that M45, Pleiades was visible over my house to the West, so I thought, let’s have a go at deciding once and for all whether I could see nebulosity. There was NO dew, the top of the OTA was quite dry, extremely unusually. As soon as I slewed to Alcyone, there was mistiness! That decided it, I was looking at nebulosity, and to confirm I used @Nyctimene’s test: one side of Ally’s Braid vs the other. Sure enough, one side of the line of stars was distinctly fuzzy, the other black as pitch. I was very pleased.

As a final hurrah, I made yet another attempt at IC342 / Caldwell 5 / The Hidden Galaxy. A mag 9 face-on, it’s reputedly (actually) very difficult to see. Especially through a tree! Which was the case tonight. Although said tree (Sycamore, the tree-weed) had no leaves yet, I maintained my 100% record with IC342 – NOT SEEN.

So, a lot of galaxies. I was expecting it to be just one fuzzy blob after another: tick, tick, tick. But, dark-adapted, they all had noticeable shapes and it was in fact interesting, much more than just the thought of far big and how far. In the end, it was the noting them down on my phone that drove me to finish. My right-hand fingers got very cold in the 4 degrees and wind, and simply unscrewing eyepiece-holding screws was a challenge at 1am.

Once again, thanks for enduring Astronomy War and Peace vol 997

Cheers, Magnus

Does anyone use their Nexus DSC or DSC pro to control their AZ-EQ6 in alt-az mode? I’d be very interested to hear of your experiences. I’m finding it simply doesn’t work for this mount.

I had a session last night where during the afternoon I’d updated Nexus DSC firmware to the latest version, and it was still unusable (like all the 1.4.x versions I’ve tried so far). I found myself having to revert ”in the field” to the 3-year-old firmware 1.3.9h with which it was supplied, after which it was more or less fine again.

Magnus

An ultimately satisfying session tonight with my 12”: a slew of faint galaxies in Ursa Major and Coma Berenices, including Markarian’s Chain. And I confirmed finally that I was observing M45 Pleiades nebulosity rather than sudden misting of the eyepiece.

Full report to come tomorrow.

Magnus

PS and earlier the Moon with Earthshine Jupiter and Venus were stunning. I got some decent pics I think but will have to await tomorrow to get them off my DSLR.

On 21/02/2023 at 10:17, Andy ES said:

…

Almach (beautiful  gold and blue, this must be the nicest double?) …

Almach really is my favourite coloured double, nicer than Albireo (“Jewel of the Sky”) in my reckoning, and a proper double to boot, whereas Albireo is an alignment only.

Just received my copy this morning, I’m looking forward to it.

M

12 minutes ago, AstroKeith said:

Sorry - I half combined the numbers!

So the Nexus DSC latest is 1.4.14
The DSC Pro is  1.1.20

No excuses for Serge's updates (but I know he has been super busy and distracted)

Attached!

NexusDSC_release_1.4.14.zip 1.18 MB · 0 downloads NexusDSCPro_FW_1.1.20.zip 463.67 kB · 1 download

Thanks Keith I'll have a go at 1.4.14 and see what I find...

24 minutes ago, josefk said:

Hi Magnus,

I think you could add (Nexus DSC Pro):

- SAO (258,944 entries)

- Herschel (2521 entries).

Cheers

Thanks, I'd omitted the SAO catalogue as I know what it is, so in first incarnation of the list I didn't bother including it (I created the list just for my own edification to begin with, then thought it might be useful for others). I've added it. The Herschel (2521), as far as I can tell it's a combination of Clusters and Nebulae? Just so I know where to put them as an edit.

Thanks Keith. Yes my Nexus DSC (non-pro) has a few bugs too. It was supplied in March 2020 IIRC with firmware 1.3.9h . I use it to control my AZ-EQ6, and with that it’s mostly fine but occasionally goes berserk. I think there was a new firmware release a few months ago, to 1.4.8 then 1.4.11, which I upgraded to, but it introduced lots more problems for controlling the AZ-EQ6 in AZ mode to the extent of making it unusable. I’ve had to revert to 1.3.9h . Serge did try to call me a few weeks ago after I emailed him but I missed the call. I should try again to get in touch.

@AstroKeith what do your Version numbers refer to? My Nexus DSC is 1.3.9 or 1.4.x, perhaps the 1.1.x are for the pro?

Magnus

I think a good many of us use a Nexus unit or Nexus DSC to control or communicate with our mounts. I can't find a dedicated "owners' thread" so here it is. I use a Nexus DSC to control 2 mounts: an AZ-EQ6 and an AOK Ayoii with encoders.

One very good thing about the Nexus DSC is that it has 60-70 separate catalogues, some huge, which you can tick on or off to guide what you want to show up when you're in the field selecting targets. However, these catalogues are all in "abbreviated name" form on the Nexus DSC screen and it's not possible within the unit, when choosing, to see a description of what, say, the CGCS catalogue actually comprises (this one is a very nice catalogue, actually - Catalogue of Galactic Carbon Stars).

As a first contribution, I thought I might provide a list of all that appear in Serge's latest release, with a brief description of what they are. I've re-sorted them here by category, but within the category they appear in the same order as they would in the Nexus DSC. I’ve also omitted some that are self-explanatory (such as “Sun & Planets”). I hope this is useful. the list is certainly going to help me get the most out of this.

Also, It would be great if other Nexus users might use this thread to discuss issues etc.

Cheers, Magnus

NEXUS DSC CATALOGUES

Clusters (Open and Globular)
Lynga
ACO & ACO S
Abell
Berkeley
Collinder - 471 OCs
Czernik - 45 OCs
Dolidze – 57 OCs
King - 27 OCs?
Melotte – 250 OCs and GCs
Palomar GCs – 15 of the very faintest globs
Pismis – 24 OCs and 2 GCs
Ruprecht – can’t find info
Stock – OCs
Terzan – 11 GCs
Trumpler – 37 OCs

Nebulae (Planetary & Extended)
Abell PNs
Henize -  ?
Kohoutek – hundreds of PNs?
LBN – Lynd’s Bright Nebulae
Minkowski – nearly 200 PNs
Perek-Kohoutek – hundreds
NEXUS-DSC generic PNs (presumably all)
Sharpless – 313 Hii nebulous regions

Galaxies
Arakelian - 621 high-surface-brightness galaxies
Arp – Arp's peculiar galaxies
HCG – Hickson’s Compact Groups
Markarian – high UV galaxies
RFGC – Revised Flat Galaxy Catalogue – 4236 ultra-flat galaxies
UGC – Uppsala General Catalogue of 12,921 Northern Hemisphere galaxies >1’ & mag14.5
UGCA – Addendum to UGC, >400, mostly Southern Hemishpere “a hodgepodge of extra galaxies”
CGCG – Catalogue of Galaxies and Clusters of Galaxies: compiled by F Zwicky 1961–68, contains 29,418 galaxies and 9,134 galaxy clusters
MCG - Morphological Catalogue of Galaxies, 30,642 up to mag 15
PGC - Principal Galaxies Catalogue: 131,601 galaxies with extra data eg radial velocities and position angles

Other/Misc/Combinations
Barnard – dark regions
Caldwell - 109 star clusters, nebulae, and galaxies
ESO – catalogue of observations European Southern Observatory I think
Herschel – (2,521 various objects)
IC – supplement to the NGC list

Stars
Bayer – beta Orionis, etc
Flamsteed – eg 61 Cygni
CGCS – Catalogue of Galactic Carbon Stars
GCVS – General Catalogue of Variable Stars (>52,000 members)
Henry Draper – 225,300 stars with Spectroscopic Classifications
Hipparcos Stars - 118,218 stars charted with the highest precision (Hipparcos satellite)
SAO - (258,944)

Double Stars
Burnham
J Herschel
F Struve – Friedrich Struve (not sure what A & B denote)
O Struve – likewise (not sure what (A) represents
ADS – Aitken Double Stars, successor to Burnham, 17180 doubles within 120degs of N Pole
Washington Double Stars – 155,438 systems

On the recommendation of a thread in the Lounge:

Lovely image but I actually laughed out loud when I saw the captioned images well before I scrolled down to the comet image, which I thought was therefore going to be a horror show. But quite the opposite … very nice.

Magnus

Lovely account Dave, a rare night to remember. And just one scope but what a “just one” to have. Very nice. I have actually more than once failed to get out on a perfectly viable night through pure indecision about whether this scope or that one or the other.

Magnus

If you’ve visited the “What Did the Postman Bring” thread or my “New Forever Scope” thread, you might have noticed that I have within the last few days taken delivery of what appears to be a very nice telescope indeed: a Stellarvue SVX140T 140mm f/6.7 refractor. That thread details the scope’s arrival, inspection (and showing off!) and First Light from the point of view of the equipment. This report will try to adhere to the Observation storyline, though I cannot promise to avoid gushing about the scope too 😊 . Forgive me if I do.

Of course, arrival of a brand new scope more or less guarantees appalling weather, and at the moment of delivery it was bright and sunny. Quite literally as soon as I extracted it from the box about 30 minutes later, deep fog had descended and the forecast suggested it would remain as such for a week. I couldn’t have looked through it that day anyway, as its Losmandy plate had been sent in another package which was due the following day. Sure enough, the low cloud and deep fog stayed all through the next couple of days.

Suddenly yesterday the forecast changed, as did the current weather and it started to look likely that 6pm to 10pm would be reasonably clear. And so it proved.

During late afternoon light I set out my Planet and AZ-EQ6 close in under a tall hedge and tree. There was a brisk and gusty Westerly wind that would normally have discouraged me from a session. Not tonight though, and the location, although completely blocking anything West of the Meridian, was well-protected from the wind. Of course I put in my WO 45 degree erecting prism to have a daytime look around at the obligatory local cattle-feeding tanks etc.

By 7pm it was dark enough and I brought everything else out: Nexus DSC, battery, cables, eyepiece case. I could see that although there were clearish patches, the fast-moving weather meant it was going to be a cloud-dodging evening. In the event it was never perfectly clear, but it was occasionally perfectly obscured. Cloud seemed to magically appear just when I’d chosen a star for Alignment. Eventually I aligned on Castor and Betelgeuse. I did my first Star-Test whilst on Betelgeuse and as mentioned elsewhere I was extremely surprised it was a textbook-perfect test. I later repeated the experience on, of all stars, Sirius with the same result. I’ve read that the test is so sensitive that even superb refractors will fail to some degree. I later went to Suiter’s book to see what it should look like and there it was: exactly as printed, +/- 5 waves defocus, no variation in sharpness or brightness either side. Sorry! Sorry! I’m gushing, I said I wouldn’t!

Anyway, the observing. I hadn’t really had time to plan so I had to go by memory and just a few Usual Suspects. Naturally I went to M42 first. The first thing I noticed was the nebulosity around the Trapezium was better than I was expecting in a 140mm scope. I’ve seen it many times here in my 12”, but this was not disappointing. As I stared at the Trapezium itself, with Delos 6 for 156x, the four main stars were not perfect pinpoints but they were small and reasonably stable. Enough that the E was easily evident and the F definitely appeared unambiguous from time to time.

One thing I’d neglected to remember that whilst Newtonian-observing is mostly standing, a refractor’s eyepiece is at the other end of the tube. I hadn’t got my observing chair out, so:

I visited Sigma Orionis, that nice 4-star system, noting that the faint C star was quite obvious. Moving up to Alnitak (the Eastern-most of the Belt) I did split the tight double but it wasn’t what I’d call razor-clean. I went to Rigel to split that easily enough, the tiny companion well clear of Rigel’s scintillation. Of course, I had to try Sirius, and decided pretty quickly there would be no Pup tonight. I’ve seen it once only, through my 12”. But I did star-test again on Sirius with the same amazing result as before, although somewhat more colourful. Perhaps I should have persisted with more patience and higher magnification, but that was not tonight’s purpose. Besides, every few seconds I’d have to wait for a band of cloud to pass over.

Now I wanted to try wide-field, so I selected my Nagler 31 giving me 30x and a 2.7 degree field. M45 Pleiades was out of the question, behind the sheltering hedge. As I write I notice that the Comet was quite near Bellatrix but I didn’t know at the time. Besides, probably too cloudy. I could see the Beehive naked eye, but it doesn’t appear in the Nexus DSC’s “Common Named” list, and I’d forgotten that Beehive is also M44. So I selected instead the Christmas Tree Cluster, NGC 2264, up East of Betelgeuse. Lovely, beyond lovely! I somehow found in the Nexus DSC unit an Open Cluster not far away that the Nexus’ notes gave a name to, something like Coal Tower Cluster, but looking at charts now I can’t find nearby OCs with similar names. I’ll have to have a look again “in the field” and try to replicated how I found it and remember. Anyway, it was very nice.

Seeing as this scope will excel as a Lunar and Planetary instrument, I decided for a quick go at Mars, up again at 156x, although it was partially obstructed by branches from the tree nearby. I caught some nice detail for no more than a tantalizing second before it was consumed by cloud. Grrrr! And it’s rapidly shrinking at the moment so I’m not sure if I’ll get another decent opportunity in the near future.

I finished off with a quick look at Mizar, always a beauty.

Whilst this was a fairly mundane list of targets, for this session that wasn’t the point. This was about getting used to the scope and as First Lights go amongst my scopes, it was the best I’ve had, not least because a suitable night appeared almost immediately on receiving it. And it served its purpose: I am now comforted that this scope qualifies as an exquisite instrument, and poor sessions down the road will be down to other factors. I look forward now to the Moon rising, and perhaps trying my hand at sketching.

Thanks for sharing my joy, Magnus

10 minutes ago, Louis D said:

I remember trying that with a pair of surplus prisms cemented at 90 degrees in a home brew finder scope in the late 90s.  IIRC, it does work, but you have to stand at 90 degrees to the OTA, facing the hypotenuse side of the eyepiece holding diagonal to get the image in the right orientation.  Otherwise, it's rotated 90 degrees if you stand behind your OTA.

Yes indeed, just as you say. I'm not sure I'm going to use it in the field (I may) but I was curious. Using T-2 fit diagonals might save some in-travel by screwing the one directly to the other, perhaps requiring a small spacer to get it to bind in the right position.

1 minute ago, markse68 said:

I’m intrigued 🤔 and feeling very dense and unobservant 🤣 and trying to analyse my mind haha Don’t tell me though- I think i may need to look again on a bigger screen than my phone unless it’s hiding in plain sight. I did notice something odd in one of your images- are you using 2 diagonals to get un-mirrored view?

Mark

YES! Well done … my proprietary Porro setup. It works! And as far as I could tell, no vignetting with 18.2 DeLite inserted. 😁😁

13 minutes ago, markse68 said:

Not jealous. Not jealous. Sounds truly wonderful  Have you got a phone holder Magnus? Would be great to see a perfect startest, and the ones from your top tier newts

Mark

I don't have a phone holder, I do need to get one. I keep trying to learn @Stu's hand-holding skills but for a photo and comparison of a pair of star-tests I fear a phone holder would be needed. I do have a DSLR bayonet to 2" adapter though and lots and lots of in-travel available. I'll do it that way.

By the way, in one or two of the images earlier I laid a trap especially for you and those of your mind: I was sure you'd notice but so far nobody has .

Well, First Light has happened. I was having to dodge cloud-bands and there was never perfect clarity. The MW normally striking was hardly evident. But there were enough gaps to make it worthwhile. I’ll write it up as an Observing Report tomorrow.

This thread isn’t about what I saw but what I saw it through. And all I can say is WOW.

I’m no expert at star-testing, but I do star-test every time I look through a scope if I can. I have some supposedly exalted scopes: an LZOS, two 1/10-wave newts included. But I’ve almost always had to find excuses as to why the ring-pattern wasn’t identical one side from the other. Always soft and/or spiky one side, sharp the other, or too turbulent to see at all. To be fair, there have always in my opinion been good reasons.

But this scope, tonight, a night of only slightly above average seeing I’d say, I could not tell the difference inside or outside focus (~5 waves). The patterns were identical and both sides totally SHARP sets of well-defined rings. No spikiness or softness either side. Quite unlike any star-test I’ve ever done. And seeing wasn’t great.

[edit: I went to Suiter’s book to see what the patterns should look like. And his images of “perfect unobstructed aperture, polychromatic” were _exactly_ what I was seeing, both sides. Amazing.]

At 160x Trapezium E and F were for moments between passing haze, totally “just there”. The C in Sigma Ori was easily evident. At lower power, 30x with my Nagler 31, open clusters were beyond-description lovely.

I am so happy with this scope 🙂🙂🙂. I cannot wait for the moon to come along, I never thought I’d think that!

First Light beckons. Out and cooling. Although it’s rather windy, I’ve set up in the lee of a tree and thick hedge where it’s surprisingly sheltered. It’s supposed to be reasonably clear from about 6pm. For comparison, that’s a 88mm Kowa spotter just next to it.

Having set it up, and extended the dew shield out to full length, this is what it looks like. Even I am drooling.