Clarkey

Adding more data is always diminishing returns - only you can decide the cut-off point. Personally, I rarely do less than about 8 hours per image and often more - especially for NB. You could add some RGB for the stars which will help with the overall 'feel' of the target.

I think you need to remember that in astrophotography terms, planets and galaxies are very different beasts. Planets are much more forgiving in terms of tracking, but you will want plenty of focal length and a high focal ratio is not a problem. Galaxies require much longer imaging times and need a good mount, guiding for all bar one or two and suitable FL for the camera.

You do not say what your budget needs to include. Is it camera, mount and scope? Maybe give a little more detail and it will make it easier to advise. To be honest, for that budget you will be hard pressed to cover planets and deep sky targets effectively.

I live on the edge of town (Bortle 5/6) and I do not find LPF's useful. Particularly, if you have a lot of LED lights they don't work very well in my opinion. Personally, I try to collect as many photons as possible and remove any gradients in processing. If you have one particular type of light such as sodium or mercury vapour you might benefit from filters - but to be honest these are becoming quite rare these days.

I would suggest that a good astro specific gradient removal is worthwhile.  I mainly use APP for gradient removal (of if I have the time PI). Whilst Affinity is quite good the gradient removal is not as good, and you tend to get something that looks a little too 'flat'.

I think it depends how sensitive your set up is to temperature changes and how remote your imaging is. If over the night your rig needs refocusing then running an auto focuser is much easier. Also, if like me you like to stay in the warm whilst imaging it is a lot nicer. If you spend the evening 'babysitting' the rig it is probably less critical.

10 hours ago, vlaiv said:

Set temperature as low as you can manage given your ambient conditions.

I would add that this is true for running on a mains supply. If you are running on a battery supply, you might want to increase this to reduce the power consumed.

How are you powering the mount? SW mounts do seem a bit fickle about voltages.

As @Elp states the 224 is a capable camera and many planetary imagers still use it. The smaller pixels on the 678 may mean you don't really need a barlow with the Mak - so the savings on the that will slightly offset the camera cost.

At the end of the day there are so many options.... Just to confuse things more here is a good summary of the ZWO range. Might be worth a read:

Agena AstroProducts Guide to ZWO Astronomy Cameras

I think the main comment I would make is to get your guiding and dithering set up as a priority. The data here looks pretty good, but for a relatively noisy DSLR you will always struggle a bit without dithering. There is very little evidence of walking noise which suggests your polar alignment and tracking is good too. With dithering enabled I suspect you would get a very good rendition of this without too much more integration time (depending on your skies etc).

Without guiding you are always going to be oversampling at 1000mm FL. Your tracking needs to be about half your image resolution which is certainly not going to be the case with a large newt on an HEQ5. Realistically you will be doing well if you can get anywhere near 2" per pixel. I image with a AZ-EQ6 and I will aim for about 1" per pixel with guiding and good seeing . Typically it is normally nearer 1.5" depending on the quality of the images in terms of FWHM of the stars.

If you bin you data you will get a faster system that will help alleviate some of the tracking errors and help with shorter exposures. Depending on where you are good seeing is not common is the UK so the pixel scale is a bit irrelevant in terms of seeing when you are not even guiding.

I would say for planetary a laptop. You can use it for the capture and processing using standard windows software. It would not need to be anything too fancy as long as it has an SSD drive with USB 3 for high frame rates. A reasonable second hand one would be fine. I use a Lenovo S340 pentium and it is fine.

The benefit of the ASIAIR is when you want to power/guide/capture in a single package. Then it would be worth considering.

I think the 55.6 looks best but not perfect. What does it look like in colour? I am just wondering whether there is some minor CA effect. If you could try it at a single frequency with a filter (or show a colour image) it might give a better idea.

Edit: looking back at my ED80 images, this is not much worse than mine with a slightly smaller sensor. Also the 'smear' was mainly the blue halo so caused by CA. Maybe the best option is not to look too closely😁

Maybe take a dark image and see if there are hot pixels in this area. It does look very regular for hot pixels though. I am still using a darks library that is at least a couple of years old and it still seems to work fine.

2 hours ago, jock1958 said:

My setup consists of a dew strap connected up to a power bank similar to @wookie1965 charged up battery lasts at least three good sessions. 

Surely Taks have their own branded green dew heaters. The look of that scope has been ruined by a clunky black band.🤣

Ok I admit it - Tak envy🙁

14 hours ago, poogle said:

The image might benefit from less stars, but StarNet2 would not play along.

I find there is a bit of an obsession these days about removing stars. They are what is in the sky, why remove them? I usually leave then in (maybe less stretched) as I find it can look completely unnatural without them.

Well done on the mosaic though - I can't see the join so that must be good!

I think the Mak option would be a good one for planetary and lunar. The closed tube would be quite robust for transportation and the long FL would suit too. To be honest the mount is more likely to be an issue for transportation. The only real -ve of a Mak is the limited FOV. If you get bored with the planets and moon there is less flexibility when compared with the heritage range.

I don't think the ST refractor is good, not only for the FL, but the low F ratio will give lots of CA on bright objects such as planets.

I would agree that if you can get a cheap CCD then go for it. I started with a DSLR and they are a good entry into AP. Also second hand you are not going to lose much if you upgrade later.

FWIW I have a modified Canon 600D that I was about to sell. Probably wanting more than £250 though, but it does include a whole load of other stuff (cases, 3 lenses, m48 and m42 T-rings, wireless intervalometer, remote, batteries, CLS filter, dummy battery, memory card etc). PM me if you are interested.

6 hours ago, the lemming said:

What software would you recommend for stacking please?

Thinking about it, the rejection only works with dithering. However, even if you could manually dither a little, even in one axis it would allow the rejection to work. Personally I use Astro Pixel Processor but it's quite costly. 

My climbing kit greatly exceeds my talent much in the same way my 130p exceeds my astronomy skills.

Maybe not quite the same consequences🤣

Hot pixels are difficult to avoid really - the best option is dithering. If you use a decent stacking algorithm you should be able to negate the hot pixels though.

29 minutes ago, barbulo said:

increasing the integration time.

I think this^ is the most important. Given your set up without guiding I would suggest 30 second exposures is probably about right. However, given the very low exposure time this is a good result.  M27 has quite a high surface brightness which certainly helps. If you have more time, you will be able to stretch the data a bit more without introducing too much noise.

6 minutes ago, pipnina said:

theoretical 50 years I have left on this sphere

That's just showing off🤣

But seriously, I am a bit like you. I have tried various options but come to the conclusion the refractors are the simplest option. I am in the process of building a back garden observatory which will house 3 refractors across two mounts and a variety of focal lengths from 910 to 180mm. Given the number of clear nights in Cumbria that should be enough. I have looked at the RASA option and it might still happen one day.  Just need to sell the kids.....😀

You could consider something like this in the bags:

Fifth Gear 2 x 1kg Silica Gel Car Dehumidifier, Dry Air, Reusable Moisture Absorber Bag, Automotive Dehumidifier, Keep Windows Fog-Free. Prevents Condensation and Mold, Includes 2 x Anti Slip Mat : Amazon.co.uk: Home & Kitchen

I used to use something similar for putting a tent away if it was damp. You can just chuck them in the microwave for a few minutes to re-charge them. I have not used them for astro gear as mine just comes in the back door, but I am sure they would help.

16 minutes ago, Ratlet said:

I've got the SVBONY one.  It's built like a brick proverbial.  Except the screws that clamp it which are pants.

Agreed. Used mine with an FMA 180 and works well.

2 hours ago, WilliamAstro said:

Should i get an off brand guidescope like this for example?

Either would work fine with your scope. The small f4 scopes are fine for shorter focal length imaging and are small and light - and if you focus them as in daylight as Elp suggests they are fine. The larger 50mm scope will give more scope for longer FL imaging later, but you might need a larger mount (assuming it is being used with the SA 2i)

1 hour ago, Anthonyexmouth said:

Be nice to get the guide scope closer to the centre of rotation. 

Can I ask why?

On a separate point, have you mounted both on an heq5? I had a similar dual rig on an AZ-EQ6 and it was on the weight limit. Admittedly I had a hefty bar, two dual saddles including an alignment one plus a mini PC and powerbox. Still looks like a lot though.

Don't ask me. 2D printing is a struggle for me🤣