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I've been puzzling over the bits of Virgo that are filled with galaxies on and off for the last three months & always seem to get lost and confused among barely-visible smudges in the eyepiece of my 127 Mak.
Whilst not the ideal galaxy hunting tool, I have really enjoyed views of M81 & M82 and the Leo Trio so figured I ought to at least be able to identify the whereabouts of some of the Virgo cluster even if there's no real features or structure to be even dimly seen with this aperture. To date I'd positively identified M86 & M84 and noted a couple of NGCs in the same field and other smudges within a couple of panning fields distant - but beyond that it was all "might be" in terms of identification.
There is I admit a part of me that is motivated to "tick off" Messier objects but I want to be positive on my identification, so with this in mind I hatched a plan to tour the area in a more structured way, inspired by this great thread on the topic from @MercianDabbler https://stargazerslounge.com/topic/375174-easter-2021-attempting-galaxies-with-an-sp102/?tab=comments#comment-4074628.
Recon sessions with the ST80 while the moon has been dominant over the last couple of weeks had led me to a chain of mini asterisms that I reckon I could follow from Vindemiatrix as a pathway to identify specific galaxies - even though they would be little more than un-resolvable fuzzy stars in my 'scope. I went as far as running through my star hopping "moves" a couple of times in Stellarium during the afternoon and making step by step instructions in my notebook (I find paper & a red headtorch easier in the field than trying to manipulate an App under a redlight). Saturday's forecast wasn't perfect for this purpose but looking ahead, looked like the only usable night for a while so I spent a happy few-bank holiday hours in the afternoon packing gear, charging batteries and prepping.
All observations with a Skywatcher Mak 127, Baader Hyperion 24mm (68 degree AFOV delivering a shade over 1 degree TFOV), Baader Neodymium Filter added for good luck!
Saturday May 1st /Sunday May 2nd was clear over Bortle-5 Winchester and seeing was very steady, transparency was fair and at times poor with high cloud building gradually to the SW by midnight when I set out. There were a couple of hours before the moon became a factor so I got to work aligning (Vega, Arcuturus) and slewing to Vindemiatrix.
Tracked a couple of fields of view (1 degree field) SSW to a faint "crown" of stars [Stellarium says HD111132 is at the head of the curve] which I've been calling mini-Corona and from there on W to a 4 star asterism with Rho Virginis at its centre which I've been calling the "plane" as it looks like a clear delta-wing shape (like an old dinky toy Dassault Mirage I had as a kid!)
M59/M60 - Put the "nose" of the plane in the centre-bottom of the field and pan up half a degree and there was M59 & M60, the first a dim fuzzy point, better in averted vision, the second notably brighter and with haze around a central point, could stand direct vision.
Putting the nose of the "plane" this time in the right hand side of the finder (RACI view on the Mak) and tracking a full field West brings the first of two pairs of stars in a just about horizontal line [Stellarium says these are HD109815, HD109684, HD109486, HD109401].
M58 - Putting the first pair of "the line" in the bottom R of the finder and tracking up 1/2 a field brought me a fuzzy patch with a star bottom R [later confirmed star as HD109771]
M89 - Putting the second pair of "the line" in the bottom R of the finder and tracking up just over a field, passing a small triangle of stars, brings in M89 - a fuzzy star, not much else to note.
M90 - Putting M89 in the bottom centre of the field brings in M90 in the top of the view, dim fuzzy but a bit more of a vertical line than a point this time. Makes a nice field with M89.
M87 - Placed M89 top R in field and swing W. M87 - not as bright as expected, nebulous patch, no detail to speak of.
M86 - Placed M87 in far R of field and tracked W I full field (1 degree) - quite apparent fuzz with brighter core - easier to see than M87 which is odd.
M84 - Placed M87 in far R of field and tracked W I full field (1 degree) - faint, best with averted vision when focussed on M86.
I then tracked one field of view NE of the M84/M86 view and this gives a really humbling view full of tiny fuzzy patches.
I made a rough sketch of a pronounced Scalene Triangle of resolvable stars [based on Stellarium I think these are three 10th Mag stars just into Coma Berenices, TYC 880-659-1, TYC 880 567-1, TYC 880 505-1, whatever that means...] with an elongated "M" shape of fuzzy blobs interweaving. I am not 100% sure which I was seeing but reckon given the slightly off transparency conditions I wasn't able to see as deep as the scope's limiting magnitude of 13.1 so am fairly sure I was looking at "The Eyes" - NGC 4435 & 4438 and then probably NGC 4459, NGC 4461, NGC 4473 & NGC 4477.
M56 - I was getting spots before the eyes by this time and noted that transparency was better behind me to the NE, I took a quick look straight down from Lyra & found M56, a fairly diffuse & dim globular that I am not at all sure I would have spotted had I not just spent a couple of hours tracking down the faintest of fuzz-patches!
Finally looking around I noticed Serpens looked clear and did an opportunistic GoTo for a quick look for M5 before calling it a night.
M5 - Wow! After all that faint stuff this is an absolute corker, tight globular and bright with faint diamond dust at 63x - although it was late I switched to the Baader Zoom & upped the magnification enjoying some super views at around 150x.
Decided to end on this stunner and returned home on a bit of a high for a glass of wine and some poring over the Cambridge Star Atlas and Stellarium on my phone to confirm sightings and then read up on some of the amazing objects I'd glimpsed. Tonight I'd upped my personal "distance record" to around 70 Million light years and was amazed to find that M56 is almost as old as the universe itself at 13.5 Billion years, and even better used to be part of something called the "Gaia Sausage" - who knew?
As often is the case I finished up by reading some of the history of the objects first categorisation, marvelling again at what Messier, Mechain and the Herschels achieved.
Mind blown again...Clear (dark) skies!
After many hours of fiddling round with Registax wavelet settings to process my own solar system images, I've always been curious as to how it actually works. In doing so I've put together my own image sharpening program which does something similar to Registax wavelets. For comparison, I've also added some general purpose deconvolution techniques which you'll probably be familiar with from other image processing software (like Wiener inverse filtering, Richardson-Lucy, etc). In choosing a point spread function to deconvolve with, one suprising result was that the typical stack outputs from Autostakkert work best with a Lorentz point spread function (with a minor modification). Deconvolving with a Gaussian point spread function doesn't really work. Deep-sky images seem to deconvolve best with a Moffat point spread function (which is to be expected - it's already well established that star profiles in long exposures are best approximated with a Moffat function).
On the whole, it's unlikely that you can sharpen solar system images much more in this program than you already can in Registax. You can see results from Registax wavelet (sharpening layers), inverse filtering (e.g. Wiener), and iterative deconvolution (e.g. Landweber) below. They all give very similar results. In all the techniques there's a similar trade-off between less noise but less detail vs more noise but more detail.
There are some quick start notes on the first page of the Readme here:
There are some examples of deconvolved images here (move mouse over image to see before/after):
Image credits are on the hyperlinks
The Windows download is here:
Example solar system tifs to experiment with are here:
And the project page is here (with Source code in the src folder)
If anyone finds it useful, do post here how it compares to other tools you use for solar system image sharpening.
The download and the source code are free, you can use it unrestricted for any purpose. The OpenCV and OpenCVCSharp components which my program use have licence information at the end of the Readme.pdf.
I saved the original packing for my Mak127 and have supplemented it with a cut-up foam sleep mat and a strip of sticky Velcro. Now all fits snugly in a standard sports bag with room to spare for finders, diagonal etc. Star Adventurer tripod + AZ GTI an easy carry - all seems safe, ready to Grab and Go!
(Originally posted this in the wrong section Notes from 10.2. )
Had three sessions last night, the first the CPRE Orion star count with my 11 year old daughter, magic.
The second was from the light-blighted garden mid evening - successfully picked up M41, M35 and M67 all for the first time - then a neighbour put on more lights so had a go at Polaris, nearly, almost sort of resolved as a double this time.
After a tea and warm break I managed to convince myself that the Mak 127 carry over to the park at 11:30 pm constituted allowable lockdown exercise (body AND mind officer...) so headed out to a wider and, it turned out, reasonably darker viewing spot in the park.
I haven't yet much comparative experience of conditions but I would say seeing was quite steady while transparency a bit milky. Winchester sits in a river valley and I suspect this may be a local feature until I can get up & out of town. Anyhoo, what started as proof-of-concept of some grab & go bag & padding ideas, turned into a really super session of clusters and doubles, most of which I had never seen before, & fruitless searches for fainter things.
Technique-wise I brightest star aligned on Sirius and Arcturus & did have a few accuracy niggles with the GoTo , however a combination of the Telrad + 10x50 Bino sweeps got most of the bright targets quickly in the Finderscope and centred. Highlight has to be the Beehive, M44 which I found breathtaking & can't believe I have never looked for before, Beta Mono triple-star which was amazingly 3D and set me off on a Tatooine sunset imagination-trip and M67, dim & red the kind of place where Klingons might hang out! After much reading on here over all these starless nights I had made a list and although I deviated a bit from it and failed to find ANY galaxies or planetary nebula, the list was a great idea and reminded me that I wanted to go and hunt down the targets in Cancer which I would otherwise have forgotten and missed two of the highlights of the evening. Eventually my phone battery gave out and as I was wi-fi tethered to the AZ GTi this ended my session shortly before frost-bite ensued.
That dew shield was a good buy
For what its worth, here are my notes, all observations made on SW Mak 127 on AZ GTi, Baader Hyeprion 24mm 68 degree fixed for most & occasional higher mag on Baader Hyperion 8-24mm Zoom. Telrad & SW 9x50 finder, supplemented by Celestron Nature DX ED 10x50 Bins.
My objectives on getting a new Skymax 127 were purely visual observing having parked imaging for a far-off time when I have time on my hands but, on taking delivery of a Baader Hyperion 8-24mm Zoom and fixed Hyperion 24mm 68 degree, I noticed a photo on the box and was intrigued..
My DSLR hardly gets an outing these days with an iPhone camera always on hand but I thought it has to be worth a go so I ordered a Baader M43-T2 thread ring and a Nikon T ring to connect it all together, perhaps this could be quick and dirty way of getting into basic imaging at low cost. It all connects incredibly simply in seconds and although I'm only using the supplied SW plastic-bodied diagonal feels nice and secure when its on the 'scope.
It makes quite a chunky load on the little AZ GTi mount but with the Vixen bar at its extreme balance point the mount performs fine at what I reckon is the very top end of its published 5KG payload.
Initially I just wanted to establish if there's a decently bright and focusable image that makes it to the CCD & given the absence of stars due to current weather and this being a bit of an operation to put together, a daylight test seemed a good idea. I have a very handy church spire about 500m away (about the maximum possible distance from a church in Winchester) and poking it all out of an upper storey window in failing light on an extremely windy Saturday I captured the orb below on a 2.5 s exposure - (distance view included for scale, the spire is centre frame partially in the trees).
Verdict: focussing is tricky, as you can see, but on the Skymax 127 there's definitely plenty of leeway either side with the focuser which answered my initial exam question, it just takes some focus to focus!
I've ordered the Baader heavy duty quick release system pictured on the box which should make this much safer and more practical in the dark and cold, although it does make this not quite the bargain-basement option it is with just the 2 rings.
Given the light & time limitations of the test Id say its definitely worth trying on nighttime targets, if the clouds ever clear...
Will post any results up here but this looks like a really promising way of resurrecting a Nikon D90 that has been on the dole for a while (it shoots RAW video too!)
Any hints, tips or suitable targets appreciated!