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And you call that a "guide scope" do you?

My vote would be with a mini-pc or "NUC" standing for next unit computing but essentially just a really small PC, that's for a fixed installation, if you are taking out and about yeah maybe a laptop is more what you need. If you want to capture at a high framerate the key component there is going to be disk write speed, so swap out any spinning platter HDD's for solid state drives straight away.

My little NUC is out there happily, has been for a couple of years with only a telegizmos cover on the scope for protection. no issues at all. I run a pegasus powerbox as well, so I shut down power to everything at the end of my sessions. the NUC runs on its own though.

Hi Duncan, A guide scope is a finder scope, the thing that makes it a "guide" scope is the software that you plug it into, so, you would take a normal finderscope/guide scope like a skywatcher EvoGuide 50 and you plug a camera into it. That camera then connects to a piece of software, PHD2 is very commonly used, and the software also connects to the mount. The software monitors small changes in the location of a guide star, and issues a correction to the mount. So in that respect no, its not just for alignment, its for actively guiding the mount and compensating for errors. Objects that require, or you want to use long exposures on are helped by active guiding. Solar system stuff is generally done with video, using a technique called "lucky imaging" in which you shoot many, many frames of video and post processing software picks out the best ones and stacks them together. I would recommend a dedicated astro camera over a DLSR for a number of reasons, most of which other people have called out but I would also add that a dedicated camera will have ASCOM drivers which in the long run will be easier to integrate into a full system. Post as many questions as you like! That's what we are here for. Personally I have just about finished getting my setup how I want it, its pier mounted permanently and all remotely controlled, there are some sizeable learning curves on this journey but it's immensely satisfying! Ed.

Wow that's amazing. both the object and the skill in capturing it. 20 minute subs are looong

Grab yourself a shutter release cable, that should deal with the wobble. don't bother with a Barlow, all that will do is increase magnification and crop the image. The Orion nebula will fill most of your frame there if you have enough exposure. Focus is only slightly off, to my eyes at least but a bahtinov mask will help you sort that out. A tracking mount will, ok I am going to be honest based on my experience here, a tracking mount will drive you insane for a good few sessions until you get to grips with it. Once you have nailed down setting it up and aligning it it opens the door to the incredible images you can see on this board. Orion is a bit of a special case because its so very bright and only needs "short" exposures. If you want to shoot stuff that requires exposures over 30 seconds, which is pretty much everything else in the sky, you will need to be tracking. Once you get over 60 seconds you also want to be looking at guided but don't worry about that for now. Personally I would skip the mount upgrade path, i.e. adding the tracking motors, and head straight for something like the EQ5 SynScan mount. As for stacking, yes its a bit of a mystery to start with. My route through the various options started with Deep Sky Stacker, which is free and perfectly serviceable, then onto Astro Pixel Processor which isn't free for stacking, and PixInsight for post processing which also isn't free to quite an amazing degree. During daylight you can shoot a set of calibration files and reprocess your existing image, so if you are at a loose end today you can try that. I cannot stress enough how important the calibration files are, that's the Darks, Flats, DarkFlats etc. each set does something very specific to remove noise from your image and increase Signal to Noise ratio. Here's my first Orion, 2nd January 2017, the nebula is one of the out of focus blobs, the slightly pinker one. Thats 16 sec at F1.4 ISO 400 on a Nikon D800E, 85mm lens. Ed.

this might be a bit better...

With clear skies on the radar for my ski trip I lugged the rig over to Courchevel in the French Alps, passing through the tunnel at about 2:30 on the Friday 17th having packed everything at the last minute and picked the wife and kids up from school. Not so hard for us living about 20 minutes from the tunnel but my sympathies to anyone having to cancel at the last minute due to Macron's announcement. Anyhow. here's my Orion Nebula. Its LRGB stacked in APP and processed in Pixinsight. Seems a bit overblown in the middle, not sure what to do to bring more detail out in that region, maybe dial down the luminance channel a bit? I also didn't rebuild flat and dark libraries whilst out there, too much else to do with 10 of us out there so I am using my existing libraries. same rig but a lot colder up there. also I normally shoot 120s exposures but on Orion I had to cut that to 15 sec. Not the main point of the holiday so, I am more than happy with this so far. I have the Heart Nebula and the Pleiades to play with as well. The French for "Bolt" incidentally is "Boulon" and the French for washer is "Rondelle" and a decent B&Q substitute is Weldom. here's the one in Moutiers The bolt for my pier was too long for the tripod so I had to go on a little trip. Ed.

First clear night in forever the other day, and I managed to get a good few hours on a new target, the Rosette Nebula. I'm really pleased with the result and I think it's a big step forward from my elephant trunk shot. Changes - well, I shot this with 3 minute subs not 10 and I have rebalanced the rig and dialled in what I think is my best polar alignment. PHD2 played ball all evening with only half a pixel or so of movement which is a massive improvement. I think the angle of IC1396 where I am makes it really hard on the equipment, I will go back to it and check once I am done with some other stuff. I have bought pixinsight and started putting some time into learning that. Ed

That's actually a bloody nice picture. I would be very pleased with that. Bit short on stars, obviously but otherwise very nice indeed.

As I am entering my second month of 100% cloud cover I rather wish I had chosen to study the buggers

I have been wondering for a while what the "high cloud" is, that seems to be the layer that is always contributing to the cloud cover but it's not really visible from the ground.

So its raining and miserable and looks to be staying that way. I had moved my scope inside off the pier to try re-wiring it the the garage where its dry, stable and I can clamp the thing in a vice. I lost a power cable and damaged my focuser unit last week with a cable snag so I was keen to try and prevent this in the future. Also the 30M powered USB cable gave up the ghost, flat out refused to connect to, or even see my equipment. I have been thinking about getting a remote mini-pc for a while and this seemed to be a good opportunity. This is what I have come up with. Using the right hand side mount for a guidescope shoe I have attached the Pegasus Powerbox 2 and the mini-pc back to back mounted in an aluminium chassis, then I have routed all the wires that do not move relative to the scope and cable tied them together. Only four wires should move relative to the scope, that's the NUC power, the powerbox power, the mount power ( which thinking about it I could actually opt *not* to run off the powerbox which would mean one less wire that moves ) and finally a network cable that runs to the PC. Its actually fairly well balanced because the new powerbox / PC unit counterbalances the guidescope / camera / focuser. The bunch of wires hanging down connect into power or mount, the rest of them should be static no matter where the scope points. Ed.