Budgie1

That's called Vignetting.

Yep, looks like dust particles close to the camera sensor. Check the camera sensor window and try a careful clean if you can see spots of dust on there. Normally these are on the sensor window or any filters but if you have a focal reducer or field flattener in the image train, that would also be worth checking.

I got the 45 day trail version of PI first and started by reprocessing older images I previously processed with PhotoShop. This way I could see the difference PI made to the quality of the final image and to make sure I liked the software, before forking out the full price for it. Don't be put off by the complexity of it, once you get used to the UI and get a basic workflow sorted then it makes more sense. Also make use of the ability to save your favourite/most used Process Icons down the right hand side of the screen. Then you can simply reload them on start-up.

I used the 12 part video tutorials from Mitch. My advice would be to start with the post-processing side of Pixinsight and get to know that first. You can leave the stacking to the likes of DSS and go back to the Weighted Batch Processing later.

16 years living in the Outer Hebrides sort of dulls that feeling, especially when you get the same experience sat on the sofa in your lounge! 🤣 We had a storm up there on the 17th January 2009 when my anemometer topped out at 85 knots (98 mph). It was relentless for a few hours but it was surprising how quiet it got when the wind dropped to 64 knots (74 mph or Hurricane Force on Beaufort Scale)!

I hope so, have you seen the forecast for tomorrow? Windy.com has two forecast models for the Ipswich area giving sustained winds from the Southwest of around 50 mph and gusts up to 80 mph from 12:00! 😱 This is the sort of weather we expect up here, but not not down with you, so keep an eye on it and I hope the forecasts are wrong!

A well deserving image.

You should get similar performance from them. The 294 is a few grams lighter, has a larger sensor & pixels and is slightly more sensitive. The 533 is £80 cheaper (from FLO), doesn't have the sensor glow and will be less of a faf with the calibrations frames. So it is really down to square vs rectangular sensor. I don't think you'll be disappointed with either TBH.

That's my new Darks library created this evening. Cooled to -10°C, Gain 200, Offset 30 and exposures of 45, 60, 90, 120, 180, 240, 300 & 360 seconds. All set for the next clear night, when ever that may be.

I also have the ASI294MC, which I upgraded too from a modded EOS 1300D. I feel the 4/3 sensor allows more scope for the larger targets than the 533 but you've already spotted the main choices between the two. As for the flats issue with 294, have a look at a thread I started yesterday:

Thanks @PadrePeace, I'd been keeping my eye on the thread that @scotty38 started about using the L-eXtreme with the ASI294MC back in January, but confirmation from yourself about the gain settings you're using and the link to the SharpCap thread is useful. 👍 I use the 1,25" L-eXtreme and have just got the 2" version of the Askar Duo-Band filter so I can use a filter draw with the 294MC, rather then having to remove the camera when I want to change filter. The Askar is a 7nm fitler, the same as the L-eXtreme, and with the little use I've had with it to date, seems to produce good results. It looks like I've got another week or so of clouds & storms to come, so I'll use your settings and create a Darks library and give it a go on the next clear night. Did you find you could reduce the exposure times with the added gain setting, or did you stick to what you would normally use?

The ZWO ASI294MC Pro camera has been getting a bit of a bashing of late in various threads, mainly about the difficulties getting decent Flats, which I know can be a pain and more so if you're using one of the duo-band filters. So I thought I would post an image I took on the 10th February (my second clear night so far this year! ) to show that this camera isn't all that bad and can produce some surprising images. Now, my main target for the night was M33 and I managed nearly 4 hours on that, but then the Moon started to effect the subs and it was quite close to the trees by this time, so I swapped to M42. M42 or anything close to Orion is only visible for a couple of hours for me, due to tall trees to my South. I have a gap between the trees in which I can image Orion, but not for long. On Thursday, M42 was getting a bit too close to the trees by time I started imaging it and I only managed 16 x 60s exposures before I could see branches in the subs. When it came to processing, I ended up with 12 usable frames but I went ahead and stacked them in DSS using Darks, Flats & Dark-Flats. Post-processing was done in PI with a final "enhancement" to the starless image in Topaz AI (I may have gone a bit OTT with the Sharpen AI but I was only playing ). The ASI294MC settings were: Gain 120, Offset 8, exposure 60s and fixed point cooling set to -10°C. The scope was a Skywatcher Evostar ED80 DS Pro with the 0.85 FR/FF and UV/IR cup filter only. I'm blessed with Bortle 2, so no LP filters needed. I know M42 is a bright object but, for a 12 minute exposure, I think the ASI294MC Pro has done quite well. Maybe I'll get some more subs to add to these when I get my clear night for March! 🤣

I finally got a clear night and managed to setup just after Sunset. First image is the setup imaging M33 and looking to my West at the snow covered hills. This is the view to the North with a haze of Aurora visible above the horizon.

With the likes of the ASI071MC and other cameras like it, you don't need to take your Darks frames during an imaging session because it has set point cooling, so you can recreate the sensor temperature at any time. You can simply remove the camera from the scope and take the Dark frames when convenient (cloudy days/night), as long as you use the same sensor temperature, gain & offset settings as you use for imaging. You can even build a Darks Library and take, say, 20-30 Dark frames for every exposure setting you're likely to use, then you can just reuse them. If your camera came with a cap for the sensor, then use that and put it in a box, as @ONIKKINEN suggested.

Love the colours in this one! 👍

The image hasn't been debayered during the stacking process. If you're new to PixInsight, have a look through THESE TUTORIALS, which take you through the processing and it's what I used to get started.

I got a refurbished Lenovo ThinkPad with an i7 processor & 500GB SSD for running the imaging, think I paid about £140 for it. But that's all it does, all the processing & post-processing with PI is done on my desktop with a good graphics card and plenty of RAM.

You may need to increase the gain and the exposure. The stars in your screen shot are hard to see, which makes them hard for the software to follow. With 0.5s exposures, you stand the chance of following the seeing, where the software is reacting to movement in the atmosphere, rather than actually following the star movement. Increasing the exposure time to 1-2 seconds will eliminate this. I think my ASI120MM Mini normally guides with a gain of about 48 and 2 second exposure, but start by increasing the exposure and see if it makes a difference.

With the weight of the EQ5 mount, I wouldn't like to put it on top of a standard photographic tripod. It just wouldn't be stable enough. When attached to the tripod, the EQ5 isn't that heavy to move around and is a very stable platform for visual & imaging. Also, if you want to do astrophotography, I would get the EQ5 with GoTo because it works out cheaper than fitting it later.

With the ASI294MC Pro I got from @SamAndrew I've only used the ZWO native driver and the ASCOM driver and both have the same gain settings. Software wise, I've used the ASIAir Plus but mostly I use APT, this uses the same gain & offset settings from the native & ASCOM drivers. Similar to @scotty38, I use a gain of 120, based on the ZWO information he posted above. I have only ever use this gain setting and the only setting I've tried to change is the offset. I started with an offset of 8 (seems to be the default offset for the ZWO native driver) and then tried 30 (default for the ASCOM driver). I found the noise levels on the final image went up when I use offset 30, so I went back to 8 and stuck with that. If you're not using any filter with this camera, I would advise at least trying a UV/IR cut filter because the front window in ASI294MC doesn't have this coating and it will help to control the stars. Rather then posting some of the images I've managed to get with this camera, there are a few HERE.

I'm going to throw another option into the mix and suggest the Skywatcher Evostar 80ED DS Pro with the dedicated Field Flattener/Field Reducer. This is a refractor scope and is slower than the 130/650 at F6.37 with the reducer, but gives a slightly larger field of view. It is smaller than the reflector, so less bulky on the mount and less effected by the wind. It also requires no collimation or coma correction, shorter cool-down time and has good optics and focuser for astrophotography.

Hi and welcome to SGL. Firstly, if you're not familiar with the EQ5 setup, there's a good video HERE which runs through the setup, polar alignment and setting the Home Position. The cheapest and easiest way to get started with astrophotography on your EQ5 mount is with a simple Vixen dovetail and bolt your camera to that. This will fit onto the mount and then you can do your, 1, 2 or 3 star alignment with the synscan handset. For this you'll need to use the screen on the camera in live view to locate the stars, so choose nice easy to spot stars. You can also use one of these bright stars to set the manual focus on the lens, again use live view and x10 zoom to get the focus as good as you can. Now choose your target, to start with I suggest an nice bright object like M42 Orion Nebula or M31 Andromeda, ans slew the mount to that object and start the mount tracking. It makes life easier if you have an intervalometer or remote shutter release so you're not touching the camera when you take an image. Take a test exposure at something like ISO 3200 for 10 seconds to make sure you can see the target in the field of view. Then, when you're happy with the framing, start taking images. The ISO will depend on the light pollution where you live or the Moon phase, but look at somewhere around ISO 400 to 1600. The exposure setting depends on how well your mount is tracking. You can start off with 10 seconds and increase the exposure time until the stars start to trail, then reduce it again until the stars are pin-point again. The wider the lens, then less star trails you'll notice. When you first start, you'll want to image several targets in one night (Target Hopping). Try to resist this urge and get as many exposures of one target as you can because it will give you a far better result in the end. You will also find some good tutorials to get you started in THIS THREAD and if there's anything you're not sure about then feel free to ask or do a search of the forum. Your next task will be stacking and processing your images and that's a whole subject on its own! Good luck and have fun.

I use APT and when I got my ASI294MC I used the ZWO driver, which set the offset to 8. I read about the ASCOM driver being better than the ZWO one, so I gave it a go and I'm sure that set the offset to 30 when I installed it. As it turned out, when I used the ASCOM driver, I seemed to get noisier images with it, so I went back to the ZWO native driver and put the offset back to 8. I may go back and have another go with the ASCOM driver but I'm just not getting any clear nights up here. I had one in October, none in November, five in December and none so far this month. While everyone has been having cold clear nights in the last couple of weeks, we've been under cloud. As a result, any clear nights I do get, I don't want to waste with experimentation.

These were all taken with a ZWO ASI294MC Pro, Evostar 100ED DS Pro or 80ED DS Pro on an EQ5 mount at the start of the year and later upgraded to HEQ5. IC1396 - Elephant Trunk Nebula M42 - Orion Nebula IC342 - Hidden Galaxy NGC6960 - Veil Nebula M51 - Whirlpool Galaxy

Offset of 8 is the default for the ZWO drivers, offset of 30 is the ASCOM driver default. Did you swap drivers at any stage or did the new PC use the ZWO drivers as default?