AusGuy

Thank you Mike. Cheers David

In the early test viewing / imaging session mentioned above it quickly became apparent that SharpCap will be great for EAA outreach purposes when viewing targets that have a high dynamic range such as M42. In past public viewing sessions back in the almost forgotten days before Covid-19 when using other software I needed to use a range of different exposure lengths to show visitors the full range of detail that a camera can reveal. But with SharpCap it seems that to achieve the same result one can employ just one exposure setting and simply vary the positioning of the live-stack histogram's mid-level slider. And the nice thing is that visitors will then immediately see the changes on-screen as you make them and so better appreciate that the view is real and not just manufactured.

We've had nothing but overcast and rain for quite some time now so it hasn't been possible to get out and wrestle with the new (to me) ASI294MC Pro camera and so advance a much needed learning curve. In desperation I've revisited some earlier attempts with an easy target that gets pretty high in our sky. Anyway I've managed to salvage something from what I thought were rather poor results when captured. For what it is worth here's a pretty garish mosaic of two panels. Debatable as to whether it really qualifies as EAA but the SharpCap live-stack exposure lengths for M42 were only 4 seconds and for the Running Man 4 and 8 seconds so maybe it does. Vixen R200SS; SW AZ-EQ6; ZWO ASI294MC Pro cooled to -10C; Baader MPCC SharpCap live-stacks at 310 gain. Adjusted in Photoshop and StarTools.

Just come across this thread. Long ago when living in Kenya I bought a Mark IV mount and optical parts from the Farringdon Road shop and made up a fibreglass tube for the long focal length 8 inch mirror. Some industrial flywheels acted as counterweights. All pretty “Heath Robinson” but it worked. 1980 saw the track of a great total Solar eclipse pass over the Tsavo National Park so I lugged the mount, etc. to the park and found an old tree stump to act as a pier. The image shows the mount and the the early partial phase being projected by the extremely long and rather poor quality guiding scope while waiting for totality. David

As you probably already know, M30 is a core-collapse globular cluster located in Capricornus. At nearly -23 degrees south of the celestial equator it is readily seen here in the southern hemisphere. But it is not too far south to be invisible to northerners, as is evidenced by being included in the Messier catalogue. For EAA purposes it is nice to be able to show viewers (or at least it will be when this Covid-19 pandemic is over) that it has a sprinkling of intense blue stars that can easily be seen on-screen. And that should lead to a discussion of the apparently anomalous appearance of a great many young blue O and B stars in an ancient star cluster that one would have expected by now to contain only old red M and K stars. The reason is well documented in many excellent articles on the Internet. ZWO ASI294MC Pro cooled to -10C; SkyWatcher PDS 150; SkyWatcher HEQ5 Pro; Baader MPCC. SharpCap livestack - 4 x 30 seconds at 380 gain. Minor adjustments in Photoshop.

Another view from the LMC back on 17th – the only clear night for some time before and since. It can truly be said of this region “here be giants”. The bright emission nebula NGC 1763 is commonly called the Bean Nebula, no doubt because of its curved bean-like shape. At about 280 light years in size it is eleven times the size of the Orion Nebula M42. This Hubble image https://en.wikipedia.org/wiki/NGC_1763#/media/File:N11_(Hubble).jpg nicely shows the star cluster emerging from its surrounding cloud of ionized hydrogen. Nearby nebulae NGC 1769 and NGC 1773 are of the same type. All three form part of the much larger nebulosity encompassed within the drawn circle - well shown in Dave Jurasevich's Ha image at http://www.starimager.com/Image%20Gallery%20Pages/Hydrogen%20Alpha%20Images/NGC%201763_1800_LCO%20AP12MC.html At 250 light years across the globular cluster NCG 1783 is substantially larger than the Milky Way's largest globular – Omega Centauri (170 light years). Vixen R200SS; SW AZ-EQ6; ZWO ASI294MC Pro cooled to -10C; Baader MPCC SharpCap live-stack - 6 x 2 minutes at 310 gain. Minor adjustment in Photoshop.

A break in the weather last night opened up the opportunity to revisit the LMC. Scattered early clouds meant that viewing in earnest could only begin later in the night. But that was OK because the LMC transited at about 11:30 pm giving it time to mostly climb out of the light dome over our neighbouring city. The temperature was in the high 20's C but the camera very quickly and easily cooled down to -10 C. The more I use this camera the better I like it. While waiting I had plenty of time to check polar alignment using PoleMaster and the Newt' s collimation using the Howie Glatter laser system. That this time was well spent can be seen in the night's images. No trailing of stars and no obvious coma right out into the corners of the camera's frame. The unguided equatorial mount seemed to be performing exceptionally well so I chanced using 3 minute exposures and that went well too. The attached three images are : A screenshot of SharpCap live stacking in action using an actual size zoom level – showing that the “live” view is real and not manufactured in post processing. A full resolution result of stacking 6 images. To be honest it is hardly any different from earlier stacks of 2 and 4 images and either of those could have been used here just as well. The only modification in Photoshop has been to increase contrast very slightly using levels. The same image with labels for some of the objects seen. The image bears enlargement to 100% resolution if you can manage it. The whole region is about one camera frame width away from the Tarantula nebula which lies above the top edge. Starting with the bright green nebula over on the right hand side, it is often called the Dragon's Head Nebula but another name is the Southern Seagull Nebula which I much prefer because to me the bright red emission nebula at the centre top looks much more like a dragon's head facing leftwards. Also this nebula looks quite like a seagull facing right with its wings outstretched. As you can see from the labelled version, it is made up of three separate NGC objects 2029, 2032 and 2035 which span about 330 light years. A wide field view that includes the Seagull can be found at https://astrodonimaging.com/gallery/southern-seagull-nebula/ although the labelling of NGC 2035 seems to be wrong. To the right of this grouping is the star cluster NGC 2040 embedded in a pinkish emission nebula. Above it is an emission nebula in the shape of a rose or a tulip. This Hubble image shows the cluster https://www.spacetelescope.org/images/potw1216a/ but not so much the nebula. This crop from a HaOIII image that I took some years ago shows the nebula more clearly. Taking centre stage at the top are the starkly contrasting nebulae NGCs 2014 and 2020. NGC 2014 is a bright young cluster illuminating the red emission nebula around it. As mentioned I see a dragon's head here snorting out faint flames above and to the left of it. Its neck extends downwards. From top to bottom in this image the dragon spans about 670 light years. Poised over the dragon's head is the blue halo of NGC 2020. So perhaps NGC 2014 is a saintly dragon? NGC 2020 is a curious object being caused by a young and massive Wolf-Rayet star that has ejected some of its material to create the surrounding blue nebula. Apparently it shines blue because it results from the ionisation of oxygen. I read that the hot core of the star shines roughly 200,000 times as bright as the Sun. The HST team / NASA call NGC 2014 the Cosmic Reef Nebula and have supplied a great image of it and NGC 2020 at https://www.nasa.gov/sites/default/files/atoms/files/ngc2014-ngc2020-tagged.pdf There is also a related video at https://www.youtube.com/watch?v=1qO6SG1HzyI To the left of the image is the large complex of star clusters and emission nebulae spanning at the very least 1,075 light years and made up of NGCs 1955, 1968 and 1974. Any of them would dwarf our Great Orion Nebula into insignificance. NGC 2011 is a beautiful star cluster although its grandeur is only hinted at in this image. The WikiMedia Commons image at https://commons.wikimedia.org/wiki/Category:NGC_2011#/media/File:NGC_2011_hst_08134_08_R814_G_B555_asinh.png shows it well. There are many globular clusters in the LMC. I have been unable to find a catalogue designation and so glean any information about the most obvious one in this image near the bottom-right corner. A task for a cloudy night perhaps? Vixen R200SS; SW AZ-EQ6 (in equatorial mode); ZWO ASI294MC Pro; Baader MPCC; SharpCap livestack - 6 x 3 minutes at 300 gain – cooled to -10C Bortle 4.5

Thank you for your kind comments Mike, Adrian and Robertl. They are appreciated. As to weather – mostly cloudy here at nights at the moment with the odd evening cloud free – usually when the Moon is up! Not a particularly dark sky – about Bortle 4.5. It used to be better years ago but the increasing light dome from our neighbouring city is noticeably drifting us closer to Bortle 5. David

A first “proper” image recording a near live view when out a few nights ago. The equipment and imaging details are : Vixen R200SS; SW AZ-EQ6 (in equatorial mode); ZWO ASI294MC Pro cooled to -10C; Baader MPCC; SharpCap live stack – 4 x 60 seconds at 310 gain. PS used to remove a satellite trail and very slightly improve contrast (except for the innermost part of the Tarantula to preserve detail). For southern hemisphere viewers this is old familiar territory but probably not so much for our northern friends. The main take-away I get when dwelling here is how very large are many of the objects that can seen quite easily despite the vast distance separating us. The annotated image says that the LMC is 160,000 light years distant. This is gleaned from a number of internet sources. But some other quite respectable sources put its distance at up to 170,000 light years. The quoted size measurements being based on the lower figure could therefore be understated – but only slightly. The Tarantula Nebula is clearly the star of the show but there are many other interesting tid-bits scattered around. The circle around the Tarantula indicates a diameter of 1,000 light years. But the object is not just two dimensional so who knows how big it is from front to back? Maybe larger still? In any event it can span at least ¾ of the distance between us and the Great Orion Nebula. Rather than comment on three of the few that I have individually identified (NGCs 2077, 2080 and 2074) I'll leave it to Steve Crouch's 10 hours integration image to reveal what this image only hints at – see http://members.pcug.org.au/~stevec/ngc2074_STXL16200_RC14_LHaOIIIRGB.jpg As for NGC 2100, just keep in mind the ESO image at https://www.eso.org/public/images/eso1133a/ I've used an image measuring tool to determine the quoted sizes but have struggled with NGC 2077. Based on Steve Crouch's image it is at least as big as NGC 2080. If you are already familiar with this territory you will be able to pick out at least some of the many whorls and tendrils of gas and dust that infest it. I particularly like the heart shaped nebula at 5 o'clock from NGC 2074. And all this 160,000 years ago at or about the time of the advent of modern humans. David

Thank you for your replies and welcoming encouragement Robert, Tony, Martin and Marvin. They are much appreciated. I asked the question because I do not want to tread on any toes with any future postings by falling foul of site rules whether they be explicit or even just implied. I must apologize for the seriously over-processed second image that I posted but I wanted to emphasize by exaggeration the difference in appearance between the two images. And it seems that that was to the good because, extrapolating from your comments, I understand that post-acquisition enhancement is not frowned on provided that it is explicitly declared. That being so perhaps it is sufficient to post single images that have been slightly “improved”, for example by removing any satellite streaks and slightly stretching using levels or curves to improve contrast? The aim being to enhance detail without destroying the captured on-screen appearance. David

Your guidance please. Not having posted here before and recognizing that this is an EAA forum, I'm uncertain as to what is appropriate to display. Below is the immediate result of saving a SharpCap livestack of 4 x 60 second exposures of the Rosette Nebula incorporating flat and dark frame adjustments. Below that is the same image after some enhancement using Photoshop. My guess is that the second version is not acceptable here but I'd like to confirm that before posting any more images. Vixen R200SS. SW AZ-EQ6. ZWO ASI294MC Pro. Baader MPCC, Bortle 4.5 No guiding. Thanks.