PeterC65

I just about managed an EAA session in between the banks of cloud last night, the first time I've used flat frames for EAA and they made quite a difference. No dust bunnies and much more detail, particularly at higher magnifications. I started with a test using M43, with and without the flat frames, then moved on to galaxies. All of the Leo Quartet, NGC3628 from the Leo Triplet (my favourite, despite never been able to spot it visually), NGC2683 (which is a new one for me), Markarian’s Chain, and the old favourites, M81, M82 and M51. M81 looked the best I’ve ever seen it. I finished with the Silver Streak Galaxy, NGC4216, since it contains a supernova, SN2024gy, that I observed last month. It’s still very obvious but a little less bright. There’s a full report here.

Last night I managed an EAA session in between the cloud banks. It remained clear as I let the scopes cool, then the first bank rolled in just as I was getting started. I had the Explorer 200 with x1.7 Barlow paired with the 72mm refractor, hoping to observe some faint galaxies and galaxy clusters. Last time I used the Explorer 200 with the x1.7 Barlow I kept getting distracted by dust bunnies, so I’ve purchased an A4 light pad and this time I tried using flat frames. I’ve done EAA with dark frames before, with mixed success, but this time, with the flat frames those dust bunnies were gone, and I was seeing much more detail. The dark frames take a few minutes to capture but the flat frames are quick, and I captured them for all of the filters that I might be using. As a test, I started with M43, just observing de Mairan’s Nebula with the Explorer, and it and M42 with the refractor. Using the flat frames I was able to see much more detail in the nebula. Quite an astonishing difference, so good that I captured flats for the refractor too. Not quite so much improvement with the lower magnification, but perhaps better colour rendition. I then worked my way through a bunch of smaller galaxies and galaxy clusters. All four of the Leo Quartet, NGC3185 / NGC3187 / NGC3189 / NGC3193, just fitted into the field of view of the Explorer 200 even with the Barlow. That wasn’t possible with the Leo Triplet, so I concentrated on the Hamburger Galaxy, NGC3628, which is my favourite of the three. The UFO Galaxy, NGC2683, was a new object for me and with the flat frames it showed me lots of detail with some nice dust lanes. It looked like M81, another favourite of mine, would be a bit too big for the field of view with the Explorer 200 but it just squeezed in and was the best I’ve seen it, partly due to the flat frames and partly due to the higher magnification I think. The snapshot from last night looks even better with a bit of post processing (below). M82 also looked good, if perhaps a little too purple for my liking. The flat frames seem to boost the blue channel for some reason. M51 also looked the best I’ve seen it. Markarian's Chain is always a good place to go for small faint galaxies. I could see most of the Chain with the refractor and just about make out the strange shape of NGC4438 with the Explorer 200. Last up was the Silver Streak Galaxy, NGC4216. This is a nice looking small galaxy that just happens to currently contain a supernova, SN2024gy. I’d observed it four weeks ago and wanted to see if the intensity of the supernova had reduced, which it had. This time with the flat frames I could also observe more detail, and with the refractor, its two companion galaxies, NGC4206 and NGC4222.

Since getting my AZ-EQ5 mount, I do like to have two scopes on the go when doing EEA, with differing fields of view. It's also crossed my mind that observing two different objects might be useful as I often find myself waiting for more frames to be taken and stacked. So I guess it might be interesting to have a few SS50s observing different objects and flipping between each of them as the frames came in and the stacked images improved. With my single mount I tend to let the widefield scope stack away while at the same time collecting several shorter stacks using different settings or filters with the narrow field scope. This is partly because I only have one EAA filter wheel and usually fit it to the narrower field scope.

I've added a custom landscape to Stellarium so that I know what objects are obstructed by my local skyline and I find it very useful. I didn't take a 360 degree photograph and instead measured the minimum altitude I could see at 5 degree azimuth positions using the actual scope that I use on the night in the actual position it gets used. I've recently updated this as I've changed mounts. The local horizon then appears as a yellow line on the Stellarium sky chart. It was quite a job to work out how to create the custom landscape and there are some idiosyncrasies to be aware of, so I wrote a post about it at the time which you can see here.

I think the SeeStar 50 is a great option for EAA, but it is what it is, you are stuck with those components and there is nowhere else to go. If you build your rig from components as you and I have done then you can swap and change any one of them. You can attach alternative kit to the AZ-GTi mount. You can use a different camera with the scope, or a different scope with the camera. You can add a Barlow or a reducer. Your setup gives a 0.72° field of view (assuming you are using a x0.8 reducer). That's better than the SeeStar 50 for smaller DSO. If you added a x1.8 Barlow you could observe the planets, which isn't possible with the SeeStar 50. If you got yourself an Evoguide 50 then you would have the same 1.3° field of view as the SeeStar 50 for observing larger DSO. And a guidescope like the William Optics 32mm would give you a 2.7° field of view for widefield observation. So many options ... The SeeStar 50 is great value for money, much less expensive than the sum of its component parts, and if its capabilities represent the beginning and the end of your EAA journey then that's fine.

I was using a Player One Uranus-C camera (IMX585) and a Sky-Watcher AZ-EQ5 mount (in AZ mode) and took 20 x 15s frames. I do EAA not AP, so relatively short exposures and relatively few frames, and the post processing was minimal (stretch, background removal, noise reduction). I don't see any chromatic aberration with the FMA135 and the stars are really sharp. I think this is partly because the magnification is relatively low, but I also think the scope is very well corrected. The price you pay for this is that you do need to set the back focus just right (55mm) as the field flattener is built in to the scope.

Using non-rechargeable AA batteries is quite expensive and wasteful as they won't last long. Rechargeable AA batteries have a lower terminal voltage than non-rechargeable so you will get less than 12V and that will drop slowly as the batteries discharge, so they are not recommended. The Celestron PowerTank Lithium LT 6.1Ah battery is regulated so that the terminal voltage stays at 12V throughout the whole discharge cycle, which is quite unusual.

I also used the Celestron PowerTank Lithium LT 6.1Ah battery with a SynScan AZ GOTO mount and a Skymax 127. Very similar to your mount and it would power the mount for several hours before needing a recharge. The battery straps to a tripod leg and is very unobtrusive.

If you still want to use SynScan Pro and Stellarium I would give the ASCOM route a try. That is my preferred way of connecting.

I have an Askar FMA135 and it's a fantastic scope for widefield. It still amazes me what it can capture. Here is what it showed me when I pointed it at Orion's Belt a few weeks back ... Yes, that really is the Horsehead Nebula. It would be wasted as a guide scope. I use it alongside another scope so that I have both wide and narrow field views for EAA.

Thanks for setting up these cameras. It's useful to see the sky from a different vantage point. Would you mind publishing where the camera is located and in which direction it is pointing as I'd quite like to identify the view in Stellarium? I assume that the all sky camera updates the image every minute rather than showing it real time like the Aurora camera. Is there a reason for that?

I've just downloaded SynScan Pro v2.4.16 by the way, and it won't even run on my Windows 11 laptop!

Have you checked that the SynScan Pro software is also using port 10001 for the Stellarium protocol port? My setup is the same as yours other than I am using SynScan Pro v2.4.8. I didn't need to make any changes to my firewall to get it to work. If the TCP connection doesn't work for you, it is possible to connect Stellarium to SynScan Pro via ASCOM. Doing it this way allows other software to control the mount at the same time, and I've found it makes Stellarium more responsive than using the TCP connection.

I do EAA not AP, but I'm rather pleased with this enhanced live stack snapshot of the California Nebula, NGC1499, taken on 17th January using an Askar FMA135, Uranus-C camera (IMX585), and Optolong L-eNhance filter. Just 58 frames of 15s each (that's a lot for me), with the snapshot processed very simply using Affinity Photo and Noise Exterminator. It's probably not up to AP standards but I like it!

Depending on the distance from inside to the mount, you could keep the mains power supply inside and just run the DC supply outside. I use a Nevada PS-08 mains power supply which stays just inside the patio door and gives me 13.8V which I run outside through 5m of cable to the mount. I selected the low voltage cable so as to ensure that the voltage drop along the cable was small enough to still maintained at least 12V at the mount when it was drawing the current needed for the mount, cameras, and dew heaters. The cable I use is AMC TW0203BRB.30 which is a 32/0.2 cable with a resistance of 0.0185 ohms per metre. When supplying 5A, this cable drops 0.185V per metre (counting the drops in both the positive and negative conductors) so you should be able to use it for distances up to 9m. It is possible to get cables with even lower resistance, but this one is happens to be 5mm in overall diameter which is convenient for most connectors.

Try Astro Printer. I have two of their small Bahtinov masks, one for a 55mm camera leans and one (now slightly modified with a short length of pipe) for a 30mm FMA135 scope.

You could wait for the Practical Astronomy Show on the 23rd March and have a look at the various options in the flesh.

These light pads do vary in quality. A few months ago I bought one from Amazon that turned out to have a gradient across it so I sent it back. My wife has an A3 light pad that she uses for drawing and it gives a very even light distribution with continuously variable illumination levels so I've recently bought the A4 version which performs just as well. The brand is Huion. Their light pads are relatively expensive but there is currently a 20% discount on them at Amazon. I haven't used this light pad to capture flats yet as I'm putting the finishing touches to two painted wooden cylinders that I will double sided tape to the light pad to allow it to be hooked over the end of my scopes and centred. The A4 light pad should be just big enough to use with the 8" Newtonian if it is well centred.

I've also had a go at Wolf-Rayet stars. Here's my attempt at WR134 from last November ... I can understand people buying the S50. I found myself recommending it at the last Forest of Dean Astronomy Group meeting. When you compare it with the cost and complexity of building up EAA kit from the components, it is a very compelling alternative.

It's interesting to know that you track the ISS with a finderscope, presumably slewing the scope manually to keep the ISS in the cross hairs? I was gong to see if I could get Stellarium to move the mount quickly enough and accurately enough to track the ISS, but when I do this as a simulation it does seem to be moving rather quickly. I usually have two scopes on the go when I do EAA, one narrow field and the other wide field. I could pair the 8" Newtonian with the FMA135, right at the other extreme, and use it to track the ISS since it has the same spec as a finderscope (it's much more than a finderscope by the way). You mentioned in the OP that only a small fraction of the frames were usable. Is that in part because the ISS was jumping about because of the manual tracking, and so not always in the frame? This all sounds like a very interesting EAA challenge.

Great images. I'm planning to give the ISS a try with my 8" Newtonian and x2.4 Barlow. How do you track the ISS? I've found it listed on Stellarium and am planning to use that, but the ISS moves pretty quickly.

It's looking like it might be clear here tonight, but I have a cold and feel rough, too rough even for EAA. A light pad arrived today so that I can try doing flats for EAA, so the clear skies are a surprise. Perhaps the Cloud Gods can be hoodwinked when buying kit from non-mainstream astronomy suppliers (Amazon) that is not normally aimed at astronomy.

I agree that open clusters look best when you can observe them in context, and see that they are a cluster with mostly empty space around them. I think this is true of many objects though. The two galaxy snapshots that you posted have a field of view that is three times the size of the object for example. Was the NGC object that is a star NGC603 by any chance? I came across this myself a few night ago while observing a bunch of galaxies (NGC603 is near to M33). I wonder if it's the only NGC star, and why it should be classified this way at all?

I use only the PC version of Stellarium which I think is much better than the app version. I agree that the user interface is a bit unusual, and I regularly forget about the object search and filtering tools that I mentioned above. So much so that I've now made a note to make use of them. All the objects I have listed in the Excel spreadsheet I also have listed in Stellarium Observation Lists (I have different lists for EAA and Visual, and for narrow, mid and wide field). So I can get Stellarium to highlight, say, all of the wide field objects I have listed that are suitable for EAA. This is useful for showing me where all the interesting objects are located, but it tends to push me towards observing objects from my Excel list rather than finding new ones. Hence my need to make more use of the object search ad filtering tools. I tried Cartes du Ciel a while ago but didn't think the DSO images where are good as those in Stellarium (they were monochrome as I recall).

I've had a good play with Deep Sky Planner (the trial version). The session planning aspect seems very comprehensive and I like that it also integrates an observation log system, but I think I prefer Stellarium. In Stellarium, in the Astronomical Calculations tool, there are two particularly useful tabs for selecting objects to observe. The Positions tab lets you select from a long list of object catalogues, filter on magnitude, and then order the objects by their position. The WUT (What's Up Tonight) tab is even more useful. For a selected object type, it lists those that are visible this evening, filtering on magnitude, size and how far they are above the horizon, and then ordering the objects. What I like about using Stellarium is that if you double click on any object in one of these lists the sky map slews to it and you can zoom in and take a look at what you might expect to see, or of course, slew the mount to the object. The observation log aspect of Deep Sky Planner is interesting. I keep a record of what I've observed during each session, but I use an Excel spreadsheet for doing this. Down the rows, it lists all the objects I have ever observed, and ones I've heard about and would like to observe, and across the columns it lists the dates of my sessions, with what kit I used and what I observed. So I can easily check what I saw during a particular session (by looking down a column) or when I've observed a particular object (by looking along a row). My system for recording all of this is very quick so that it doesn't become burdensome. I also use a voice recorder to record my spoken comments during the session, and the spreadsheet hyperlinks to these recordings.