Clarkey

Not to mention all the other kit required for a dual rig.... I speak from experience!

I can recommend Stella Mira 90mm triplet. Slightly wider FOV but good quality and excellent for imaging. A significant step up over the ED80. Alternatively, as you already have a good mount, you could keep the ED80 and get something with a slightly longer FL for galaxies etc? Maybe a 100 - 115mm triplet?

It did originally but it jammed the roof opening so I modified it. I had planned the design but for a number of reasons I had to make a number of modifications, this being one of them. Hindsight is a wonderful thing. Good point. I had to do a modification to a pier extension which is all held by the central bolt. So yes, it might have moved.

Due to my own idiocy, I managed to jam my HEQ5 against the door of my recently finished observatory. Seeing my guiding going to pot, I went and unjammed it after a few minutes, but the tracking now seems worse that it was previously. What I am wondering is, what have I damaged? Normally when adjusting the backlash, the motor whines, but in this case the mount was clicking. This makes me thing the gears were 'jumping'. If this is the case, I suspect I am likely to need a new worm and gear wheel in one or both axis. I was wondering two things; Firstly, has anyone done anything similar and what damage was done? Secondly, if I do need new gear wheels, where is the best place to source them? On another point - if you ever build an observatory make sure it has spring loaded doors.☹️

I would re-iterate what @Phillyo is saying about second hand. Most astro kit advertised is well looked after and you will get much more for your money. For the mount in particular I would suggest something better than the EQM-35 such as the HEQ5. The mount is by far the most important part of the set up and if you get a poor one, you will struggle from day one. Also, if you buy second hand you will lose very little if you re-sell later.

I'll add this image as it is the first image I have managed since the beginning of the summer. Unfortunately, I built myself an imaging observatory in September - so it has been cloudy ever since. Apologies to anyone in the North West UK..... This is a cluster of star clusters. This includes M103, the Fuzzy Butterfly Cluster (NGC654), the Lawnmower Cluster (NGC663), the Yin-Yang Cluster (NGC659) and IC166. Taken with a StellaMira 90mm Triplet with the 0.8 flattener reducer in LRGB using a 1600MM PRO. Processing was kept to a minimum with gradient removal, a slight stretch, levels adjustment and a bit of additional vibrance. All done in APP and Affinity.

I have a pretty basic laptop Lenovo S340 (pentium gold), and I have used it for deep-sky and planetary imaging without issue - including a dual rig. As long as it has a suitably sized SSD and USB 3 ports it should be fine. It does not need a lot of processor power. I expanded the RAM but as long as you have 8Gb or more it should be fine. If you want to use it for image processing, then obviously that is a different matter entirely. My current rigs use the Mele Quieter 2 mini PC's, which use Celeron processors. I have not tried then for planetary imaging, but I suspect they would be OK as they have extra SSD storage.

My method is relatively simple and works for me. I have a Reego collimator which I use to collimate the secondary mirror. (You can use a collimation cap or Cheshire but the LED in the Reego does make it a bit easier. However - do not buy the Reego for the RC8 as they are ridiculously expensive for what they are). I then get the primary correct using a star test. If you want to check the distance for the correct FL you can use a Ronchi grating, but I have never felt the need. It is loosely based on this method: A Procedure for Collimating Ritchey-Chrétien and Other Cassegrain Telescopes (deepskyinstruments.com) I can get away with the simple secondary collimation as there is no evidence of tilt in the mirror / focuser interface. If you have tilt here, it is more difficult. In this case you could use the method David suggests - he kindly sent me a copy too. It is certainly a thorough method, but I would not be dismantling my scope without the need to.

Welcome to SGL. If you are looking to get into imaging, you don't want to be going any lighter than the AVX in my opinion. Probably a pretty good match with the ED80. By the time you have added the camera and other kit you will be close to 2/3 of the quoted capacity which is a good rule of thumb. Looking at the selection you have, it is a pretty good range for FL and types - although with the others the Astromaster is probably a bit redundant. But as you say, there is little resale value.

Don't sweat it. It's not as hard as it is hyped up to be.

Normally yes. I have the Stella Mira version with the 48 and 42mm reducers and the measurement is from the back of that.

The spacing is normally from the back of the flattener excluding the actual thread - so you will need about 37.5mm of spacers.

There are a few cheap and cheerful scopes on Astro buy and sell at the moment. There is a newly posted 80mm APO that might be worth considering. Also, a couple of Achro's

If you are just running the mount, either would probably be OK (although I suspect 2 amp would be close when slewing). I would go for the second option which should power the mount ok for the time you need. Tracking only, the mount probably only draws about 0.5 amps.

I would take the capacity with some scepticism. Also, the total output is only 2A which might be pushing it - slewing, plus tablet, plus camera + (dew heater?). At full current draw (2A) you would probably only get a couple of hours out of this assuming it does not trip on high current. Personally, I would spend a bit more an get something a bit better.

Whatever it is, it's not coma. Either tilt as @vlaiv suggests or possibly a collimation issue. My money is on tilt. If you are using the standard focuser there is every likelyhood.

Neither for galaxies. These filters are for emission nebulae. You could add Ha using and Ha filte to a RGB image, but galaxies should be imaged in broadband. Quad band and Tri band filters are very similar, but the quad is used where there is less light pollution as I covers a broader area of the spectrum. The names are a bit misleading really as both are actually dual band. It is just one covers Ha and Oiii plus H beta, the other covers Ha and Oiii, H beta and SII.

The RC8 works OK without - I think all of the images above were at native FL without a flattener. I think if you go for a much larger sensor you might need to get a flattener, but these were all with an ASI 1600mm so you should be fine. (I think the RC6 does need a flattener). Just another point (looking at your set up), I did struggle a bit with the OAG due to odd star shapes - although this does appear to be a common problem. I use an ST80 for a guide scope and it does not seem to cause any flexing issues.

An older ED80 by the looks of it. £300 with the extra's is certainly not over the top in my opinion.

I have the StellaLyra (GSO) RC8 and use it for imaging and I have found it to be excellent. (Similar to the iOptron but there may be some differences - StellaLyra 8" f/8 M-LRS Ritchey-Chrétien Telescope OTA | First Light Optics). Personally, I think it is bargain for what you get when comparing with an SCT etc. Answering your questions in order: 1. It is a narrow FOV but excellent for smaller targets. Not really a planetary scope though, but good for galaxy imaging. 2. As long as your guiding is 1/2 your resolution you should be OK. With a binned 2x2 ASI1600 it would give you just under 1"/pixel which is probably more than your seeing can support anyway. So your mount should be OK. With the CCD47 you can reduce you FL to around 1200mm (or whatever you want within reason). 3. I cannot answer for the iOptron focuser, but the GSO one was OK - but I did swap mine for a Baader ST. Probably not essential depending how fussy you are and which auto focuser you use. There was some slight slippage but only during autofocus routines (and not enough to be a major problem). 4. Never had a problem with meridian flips. No evidence for mirror movement. Collimation is not as hard as most seem to suggest - and once collimated it hold really well. 5. Some images M51, Coma Cluster and Hickson 44 (Leo Quartet):

Ok - bit of an update. It turns out is not the wifi extender causing the problem, both PC's did some updates and this is what is preventing the wireless connection. They now won't connect anywhere in the house. So..... In my wisdom, after trying multiple setting changes suggested online, I decided to go back to the last restore point. Now the PC will not boot or do anything, even trying safe mode etc. So I have just spent the last couple of hours re-installing Windows from scratch. Then I will need to do all the astro software. To say I am a bit pi**ed off is something of an understatement. I know Windows can be pretty poor, but this is bad even for Microsoft. Let's just hope when it is all up and running again I can connect 😫

Until recently I was running my imaging rigs using a mini PC on the scope, over my standard house wifi. Anyway, over the last month or so I have built a new observatory, but unfortunately the wifi signal is not too good and now keeps dropping. To remedy this, I purchased a TP-Link powerline wifi extender. So now I have a very good wifi signal in the observatory and a LAN access point. The trouble is I can no longer remote desktop into the mini PC's over wifi. If I plug in the ethernet cable they are fine. Both have an excellent wifi signal. Obviously, this is something to do with a firewall setting or similar. However, I have tried multiple different setting changes without success. Has anyone had a similar problem - and did you come up with a solution? I am reasonably computer savvy - but this has got me a bit stumped.

I would have to echo @wimvb comments regarding the f4 scopes - unless you want to spend extra for a 'decent' one. I got the TS 6" for imaging and the MPCC I had was not up to the job, so I had to buy the aplanatic CC. (I know the specs say the MPCC should be OK - but reality showed otherwise). Also, the focuser sag made collimation very difficult - so I replaced with a Baader ST. After all the expense I was still not overly impressed as I had major problems with internal reflections from filters. After a couple of sessions I binned it and sold the extra's. Collimation was also tricky to get spot on. Overall, I wasted about £800. F5 is much more forgiving. What is wrong with a widefield refractor? Simple, reliable and very portable?

I recently purchased one from @Notty but am yet to use it in anger due to cloud (and worse, it is a tiny bit too bit for my observatory). So there might be a second hand one for sale in the coming weeks☹️ I'm not convinced about 'portable', it is heavy and bulky. Maybe I am getting old.....

OK, so the DD1 will turn on/off with the mains. That is good to know.