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Old 29-10-2019, 06:23 PM
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Join Date: Feb 2009
Location: Renmark, SA
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An Outing with the ST80

I got an ST80 a couple of months ago, and last night gave an opportunity for the first proper session with it. Transparency was excellent, although seeing poor, but it was the transparency that mattered as I was just doing low-power widefield from the back deck. Used a 32mm Plossl and 22, 13mm LVWs for this session. I'm in a Bortle class 4 zone.

In the ST80, those eyepieces yield the following magnification/TFOV/exit pupil:

32mm: 13x / 3.8* / 6.1mm
22mm: 18x / 3.6* / 4.4mm
13mm: 31x / 2.1* / 2.6mm

I started with the LMC. Even with the 32mm, all the little fuzzies stand out a lot better than in my 10x50 binos. Literally dozens of little knots with the bar of the LMC prominent, with more galactic haze, the disturbed arms of the LMC prominent to the north and a fainter disturbed area to the south of the main body. The 22mm further improved the view, just stuff everywhere. The 13mm started to show structure in the Tarantula Nebula and bought out more of the plethora of fuzzies. While at the eyepiece I drew up a crude map with the approx locations of all the objects I was seeing. I was gonna make a list, but it's just too insane. We'll let my artwork from the eyepiece do the talking.


M31

I could trace it 3/4 across the field of the 32mm Plossl. M110 appeared as a small smudge, noticeably elongated. M32 by contrast was a tiny fuzzy spot. My favourite view was with the 22mm, with which the galaxy extended almost the entire FOV, and the halo extended almost out to M32. On the M110 side, I could see that the brightness drop off was harder, and checking pics, it turns out that's the dark lane.


M33

With the sfc brightness so low, wasn't sure if I was seeing the whole galaxy or just the inner area. With the 22mm it was basically a slightly elongated faint haze with a mild brightening in the centre.


Pleiades M45

"Glittering jewels" best describe what greeted me when I swept it up with the 32mm. With the poor seeing, the twinkling made it a truly beautiful sight. I suspected the Merope Nebula (NGC 1435) and other associated haze, but I wasn't sure if I was simply seeing glare from the bright stars. My doubts were erased when I chucked in the 22mm, there it was, fanning out from Merope, the Merope Nebula. Using the 13mm gave a bit more contrast, with the nebula fanning out in a triangular fashion from Merope, to a distance equivalent from Merope to Alcyone. Alcyone, Maia, and Electra also seemed to be bathed in a faint haze, which almost bridged the gap from Merope to Electra. The central area of the cluster around the double star S437 appeared noticably darker. This is the first time I've seen the Merope Nebula, that's a tick on my astronomical bucket list.


Witch Head Nebula IC2118

I've seen reports of people observing the Witch Head in everything from large binoculars to 20" dobs. With the 22mm, I did suspect something just to the east of a line drawn from psi Eridani to HD32622, although I am not confident to call this a genuine sighting. It does however correspond to the brightest part of the Witch Head on photos.


ORION

With Orion now sparkling in the brilliant transparency, I had to make the obligatory pitstop at M42. Sensational even in the 32mm, with the nebula ridiculously bright and defined, even the little indentation and M43 clearly seen. Best view was with the 13mm, with which M42 was almost put-your-eyes-out vivid and essentially photographic in extent. The highlight was seeing a big fat tendril looping from the western side of the cloud right down to iota Orionis and NGC 1980. This faint tendril even appeared uneven in sfc brightness. The Running Man (NGC 1973/5/7) was clearly seen at all magnifications, with the dark lane easy with the 13 and 22mm LVWs. I also checked out the Zeta Orionis region. The Flame Nebula (NGC 2024) was easily seen with the dark lane with both the 13 and 22mm. I could also see NGC 2023 and IC 435, with 2023 quite a bit larger and brighter. I went for IC 434 multiple times, and with the 13mm and HB filter, I could see the faintest haze delineated by its eastern boundary (where the Horsehead is - HH itself not visible). Keeping Zeta out of the field was challenging but I succeeded in detecting very faint haze in the area between a line of two stars west of NGC 2023 and a rhombus of mag 6.2-8.3 stars to the south. I was pretty pleased with that!

I attempted the Barnards Loop, but only had the PSA out with me and was not sure where the brightest part of the loop was. As a lifelong Newtonian user, I also orienting myself difficult. I found myself jumping between the atlas and the eyepiece trying to comprehend the mirror reverse image. So with that, certainly no sighting of Barnards Loop.



California Nebula NGC 1499

I've been hearing that this is very faint and hard to observe, yet there are reports of people seeing it in binoculars. I'm happy to say, I've bagged the California. Without a filter, I could not see it with any confidence. Using the 32mm Plossl and the HB, it actually was relatively easy. It appeared as a large fat elongated glow between xi Persei and a mag 6.4 star a little over 1* north. Using the filter with the plossl was a PITA though, the eye positioning and excessive eye relief were terrible, I just couldn't get comfortable with every tiny movement of the eye causing blackouts. The 22mm LVW with the HB was far more comfortable and ergonomic, but the nebula wasn't as easily seen.


Rosette Nebula NGC 2237-9/46

As I was getting ready to wind up, I decided to check out the Rosette. Visible as a faint roundish glow with a slightly hollow middle centred on a rectangle of six stars with the 32mm and 22mm EPs. The UHC significantly enhanced the view, with the nebula now showing uneven sfc brightness and edges.

As Eta Carina was now rising, I decided to have a sweep of the area. All I can say, that with the 13mm and UHC, it was spectacular! Absolutely spectacular. Very vivid and filling the fov. Numerous other little clouds and associated clusters all over while sweeping around. The Running Chicken (IC 2944) was probably more obvious than I ever seen it. There is too much going to go into detail here, except that is was freaking AMAZING!!! It demands an entire evening on its own.

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By now it was past 2am, boy that was a quick 4 hours or so! Learnt a few things aswell. The Celestron Omni 32mm Plossl, which I originally got for this exact purpose, does not quite jive with me. The eye relief is simply too great, and aesthetically, I prefer a larger AFOV. With a filter, I find the eyepiece extremely frustrating to use, as I find my eye has to be perfectly positioned - any little bit off and it's blackouts. The 22mm LVW is close to it in TFOV and infinitely superior to use, but some objects need a bigger exit pupil as I found when observing the California Nebula.

The AZ3 mount was also an exercise in frustration whenever I wanted to aim about 40-45* or higher. Out of the box I had to loosen the alt nut slightly as it was insanely tight. Motion is better, but the thing just goes out of balance as you aim higher. Sometimes, it would hold at a certain elevation, yet other times it won't. It's a temperamental beast. Atleast this one has a panhandle, so I could hold that while observing with the heavy LVWs at higher elevations. Frustrating, but because of the low magnifications, doable.

Another thing I learnt: I want a ST102 and 28mm and 34mm ES 68* eyepieces, and a set of 2" filters. Sorry wallet.

Here's my LMC "sketch"
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