Corona Galaxies, 1st Central Milky Way of Season, First Light for deLuxe Finder, 12th May 2023

[Captain Scarlet]

Our first summer-like day this year saw daytime temperatures reach 19 degrees, and a forecast for a clear and still night, though I was concerned about rising currents as the evening cooled. Seeing was indeed somewhat poor to begin with, a combination of cooling air and likely a cooling scope too, as my new tactic to fend off dew involves bringing the actual scope out at the last minute, and simply tolerate the first few tens of minutes as the mirror cools. I spend that time collimating and lining-up finders, anyway.

Speaking of finders, tonight was First Light for my new super-finder-deluxe, the SW Evoguide 50ED, with FF, Baader T-2 prism diagonal and Panoptic 24, making it a 10x50 finder every bit as good optically as my Leica 10x50 binoculars. I found (!) the Finder very nice indeed, not only a finder but every bit a supplementary co-aligned wide-field scope too.

Collimation hadn’t shifted at all since my last session, and I aligned for the first time on Vega and Algieba (I did have to align again later, see below). I was using my Nexus DSC, and not having planned any sort of list I decided to start off with some satisfying easy targets, and then use the Nexus DSC “Tour” feature to find all PNs, CGCSs and NGCs within 7 degrees of a chosen centre point.

First target, mainly to check the seeing, was Epsilon Lyrae. With the alignment- DeLite 18.2 still in for 100x, I could not split the two doubles, they were two bits of mushy mess. I swapped in my Ethos 13 for 141x and yes I could now split them, but far from the best view I’ve had. Cooling ground and cooling scope, I guess. I moved on to the Leo Triplet, M65 and M66, easily seen through both the 12” and the finder. The third galaxy, NGC 3628, was distinct in the 12’ of course, but not so in the finder.

I headed across to Hercules to M13. The seeing seemed to be better at the slightly higher elevation (in fact it got better the whole night) and M13 was as ever entrancing, the Propeller quite easy tonight. M92 was similarly splendid. I’ve not observed M57 Ring Nebula for a while, indeed I couldn’t even see it some nights previously through my SV140, Moon and haze prevented it I think, so to see it as such a pronounced Polo tonight was gratifying. However, looking through my 10x scope, it wasn’t at all obvious which of the myriad white points was M57, though I was confident it was definitely in there somewhere. I suddenly remembered I now have a whole drawer-full of hardly-used filters, so I “popeye’d” my observing eye and went inside to retrieve my Oiii filters.

The 7-degree FoV through my finder was, pre-filter, a blaze of lovely stars, one of which was M57. Simply sticking the filter between my eye and the eyepiece, all the dimmer stars disappeared, except one! M57 was left clearly standing out on its own just where it should be, between Sheliak and Sulafat (Beta & Gamma Lyrae). So, what @Stu suggested might be one of the more difficult Messiers to catch through 10x50s, was easily seen through this, er, 10x50 monocular. But being so small, one needs to know which bright spot it is.

I went for M82, and stared at plenty of detail especially the diagonal dust-gap in the middle, moving along a little for a quick look at M81. Finally from my intended “all-stars” list I went for M51, near zenith it should have been spectacular. Unfortunately, because my deluxe finder is rather heavy, with usually only my SkySurfer V attached (which was also on the scope tonight too), I’d had to shift the whole tube further back in its rings to keep closer to balance. I knew at the time I set up that zenith-objects might be a risk. And so it proved: as the tube approached zenith and rotated around the RA-Az axis, we had Tripod-Strike!, followed by a hideous-sounding screech from inside my mount. Immediate switch-off, re-level, re-align and thankfully all good, phew! M51 would have to wait for another day.

Using Nexus DSC’s Tour feature, I chose a 7-degree field around Alphecca, Alpha Corona Borealis, as my “area”, and set my catalogues to show PNs, CGCSs (carbon stars) and NGCs (likely to be dominated by faint Corona Borealis and Hercules galaxies). I listed the objects I managed to see, and the first ones all seemed to be mag 12-14,5 galaxies: NGCs 5958, 6001, 5961, 5974, 6020, 6008, 6027, 6064. They were all faint, mostly right on the edge of averted-vision detection, and through this I learned that my galaxy-limiting magnitude was slightly over mag 14. Some supposedly brighter ones actually eluded me. I noted these and when looked up they tended to be face-on galaxies of low surface brightness, like much dimmer versions of M33 or M101. Nonetheless, it was nice to see galaxy after galaxy in close proximity. Oh for my 20” to be ready when I’ll be able to see the field of them.

Eventually, my list directed me to a non-galaxy, in the form of CGCS 3679 and later CGCS 4038. “CGCS” stands for Catalogue of Galactic Carbon Stars. Both these stars were noticeably and highly orange, and I must dedicate a future session to this category alone. Also, M56 appeared in the list, a first for me and a small globular. I checked if I could see it in my finder, yes there it was. I had been hoping for more PNs, I was really just trying pot luck on my area and I guess there aren’t many in this region. One that did pop up though was something my Nexus called “Turtle Nebula”, aka NGC 6210. As I looked through at the field of objects, there was one quite bright thing slightly more “blobby” than the neighbouring stars, so I attached my Oiii filter to the Ethos 13, and my goodness, the PN, for that was undoubtedly what it was, leapt out! Very nice.

For scope-play, that was it for the night. As I packed up, I noticed a streak of pale cloud appearing from the East, then slapped my head. It was the Milky Way, really quite prominent and parallel to the horizon. On one packing-up trip I grabbed my EOS6D and Samyang 14/2.8 and took the above 30-second exposure (non-tracked), painting my observing area briefly with my head-torch in white. As the picture shows, it’s nice to see the central part of our galaxy coming into view, and the complexity really was evident naked eye. My SQM-L showed 21.83 at zenith. It was also nice to see Antares again and the highly distinctive shape of Scorpius appearing.

A meteor streaking right from Lyra gave me my final Hurrah! Of the session.

Finally, I confirmed from a separate thread I started a few days ago, that most if not all the Messiers are detectable through 10x50. Certainly all mine were this night. Although it helped that the 10x50 in question was directed by a Nexus DSC and fixed to the OTA.

Thanks for reading, Magnus.

Edited May 15, 2023 by Captain Scarlet
meant corona not coma

[JeremyS]

Super report and pic, Magnus 👍🏻

[Stu]

Wonderful stuff Magnus, enjoyed that 👍

That Evoguide make a superb finder I bet. I didn’t think you could reach focus with a diagonal but obviously a T2 prism is short enough to get there, looks like you have a short 1.25” clamp in there too. Nice! Might have to copy that at some point 👍

[RobertI]

Lovely report Magnus, some nice finds there. I really like the finder - did you say you have a flattener fitted? Does that help with reaching focus?

[Captain Scarlet]

It really works well, totally exceeded my expectations. And yes the FF does add back focus I think, I’ll try it without and see, but anyway without the FF the curvature is _severe_, intolerable actually.

The choice of Pan 24 is very lucky. It’s the only one of all my eyepieces that can reach focus, because the nosepiece is really short. I looked at the TV site eyepiece specs, and the Pan24 has the shortest of their entire eyepiece range. I might try to get a metalshop to professionally take 10mm out of the middle of the main tube (everything unscrews cleanly) and splice it back together to give me more options.

M

[josefk]

A fantastic read this morning. Great list of objects and approach. I’ve never tried that Nexus tour feature but it sounds interesting. BTW I’m extremely jealous of your lovely location!