Clarkey

Go on. You know you want to.....

That's a pretty good image for 3.5 hours. The background looks OK to me - what's bothering you? A bit more saturation might help with getting slightly better star colours and bring out the galaxies a bit more.

Mixing sub length is absolutely fine and for brighter objects quite common. Given you are in the south east UK, I am guessing you do not have particularly dark sky, so long subs are probably not really necessary. I live in bortle 5/6 and use 2 minute subs but I could easily use 1 minute - just lots more data to process. You will not gain much from longer exposures in terms of S/N ratio unless in dark skies or narrowband. (Good video regarding exposure lengths below). https://www.google.com/search?q=dr+robin+glover+astrophotography&oq=dr&aqs=chrome.5.69i60l2j69i57j69i61j69i60j35i39l2j46i199i433i465i512.2130j0j4&client=tablet-android-asus-tpin&sourceid=chrome-mobile&ie=UTF-8#

PEC training is teaching the mount or software the periodic errors so it can pre-empt errors in tracking. I use PHD2 to guide (with a mini PC) and this has a predictive PEC algorithm that 'learns' the periodic error for the mount to improve guiding performance. Just for info I use a Mele Quieter 2 mini PC to run my set up. The advantage of a mini PC is you can choose what software to run - I use NINA and PHD2. However, it does take a fair bit of setting up to get it all working. The other good point about this mini PC is that it seems to have a pretty good wifi range.

Simple answer is Yes. Without guiding it is difficult to assess how well the mount tracks but at a relatively short FL you should be OK. Keep you subs short and be prepared to discard some and you should be fine. Try it and see how you get on. I do find my HEQ5 does need a bit of regular fettling to keep it running well.

The other thing to consider is if you need or want to add any other kit. For example you might need a new heater for the scope or lens. Also, come the winter when it is dark for longer you might want longer imaging sessions.

If you assume the heater and cooler draw about an amp each (depending on settings) a 6 amp hour battery will only give you 3 hours run time. This does not include power for the pc or other kit. I would suggest the larger power supply is the least you want for imaging, if not more. Obviously it depends on the duration of your imaging sessions and the setting you are using.

I'm still working on SWMBO to let me build my observatory. For some reason she and the kids think it is unreasonable to build it in the centre of the Football pitch garden.😁

My kits already packed away for the summer for this reason. Hence the dual rig I am working on for next season. Final image is pretty good given the lack of darkness👍

It's a good all rounder. Maybe a big short on FL for planets but a nice lightweight visual scope.

Personally I would say that unless imaging narrowband, try not to us LP filters unless absolutely necessary. Just get a good gradient removal tool. I image in Bortle 5 to 6 and don't use filters for anything in RGB. To be honest most of the lighting is LED so the benefit is pretty minimal anyway.

Maybe I should suggest it to Baader. I think I even used the sponge from the focuser box!

I put a steeltrack on my newt. To block the gap I used an oversized bit of sponge and screwed it down under the focuser. Once fitted I just cut of the excess. Works fine for imaging so it must be quite a good seal. I have two steeltracks and I have found them excellent.

I assume you cannot set mount limits on the Star Adventurer?

OCD is a wonderful thing!!

This is the one thing I find APP not so good at - at least with auto settings. Even with 100+ subs I still get residual satellite trails unless I manually set the rejection criteria. However, in general I would be producing total rubbish without the modern technology. (Some might say I still do🤣).

I have flats of <1s with the 1600mm pro and it has never been a problem. I know the 294 can be temperamental but I think it does depend on the camera.

I'm going to add another entry - the Leo triplet plus NGC 3593. To be honest it is not my best, but it is my first image using a dual scope rig. The rig is really a widefield set up, but as I was lacking in targets to try it out I had a go at this. This was taken on 18th April using a StellaMira 90mm ED Triplet with an ASI 1600mm pro for all of the luminance data. The colour data was captured using a Canon 600D on a SW Evostar ED80. The total imaging time was about 9 hours, 4.5 on each rig in 3 minute subs using NINA and synchronised dithering. Processing was in APP, and Affinity. Noise on the 600D was a problem in the warmer weather - my plan is to replace this with an IMX571 based colour camera when funds allow. Leo_Triplet_dual_AP1.tiff

Out of the replies, I seem to be the lazy one. Once set up in the back garden (which is pretty secure) I run it all remotely and normally go to bed. I have a rain alarm app and a rain sensor to wake me up. I still have to get up early to bring all the gear in, but at least I still get a good sleep.😁

I think the choice all depends on your priorities. If you want to view the moon or planets the Mak is probably the best choice. For general observing with a nod towards astro photography I would say the ED80. It's a good all rounder which is better than the price suggests. I have one and I use it for visual and AP.

I think the L-pro is more of a light pollution filter which in bortle 3 you don't need. The L-3 cuts down on the total at the blue and red ends. This will be more suitable for removing blue bloat. I managed to get away without it for my ED80 so I have not direct experience, but purely looking at the spectrum the L-3 definitely looks like the better option for you. The L-pro removes sodium and mercury vapour lines so cuts down on multiple wavelengths,

You could consider an L-3 filter which narrows the spectrum down a bit. Also, look at your processing, you may be able to reduce the stars with slightly different methods.

FWIW I set up an AZ-EQ6 with a RC8 and guide scope each time I image so it is doable. The larger mount also tracks better than the HEQ5 - whether that is by luck or design is another matter. I would not really call a 6 class mount 'portable' though.

There are lots of very good doublet refractors such the ED80 and 72. You can also pick them up second hand quite cheaply with FF's. I have and ED80 and it is excellent for the money. If you went second hand on the OTA it might leave enough in the pot for a used astro camera. Have a look on Astro buy and Sell - there are some on there now including a 61mm Sharpstar triplet with FF for under 500 pounds. Ideal if you are not guiding.

I did think of this but I really need to dither with the dslr. If I get a new astro camera it might be less of a problem. This was my plan. Just need to work out NINA choosing the right bits of kit. I'll give it a go and see what happens.....