Chris

I was thinking the same thing. A dream setup!

I know you can't fasten mirrors too tight else you get astigmatism, pinching and the like, but to have play in there with such fast optics doesn't seem great. It might need a bit of DIY then if there is no way of adjusting to remove flop. Initial thoughts are to use a few little squares of felt around the out side of the mirror, or if you can remove the primary 3 very small blobs of silicon sealant on the back of the mirror? Not too much as temp differences mean the mirror cell expands at a different rate to the mirror, and if there is too much silicon it distorts the mirror (I found this out the hard way with an f/4 newt!)

Can you send these pictures to the vendor Dave, and get their thoughts. Mirror flop can't be part of the design for super fast optics.

This is the cheapest compromised solution I can see. Could you stretch to this? It has fairly accurate stepper motors, goto, and the ali tripod vibrations can be mitigated with anti vibration pads and placing a bit of weight such as a power supply on the tripod spreader tray. I had an EQ3 Pro in my old obsy for a while and it wasn't a bad mount considering the price https://www.firstlightoptics.com/reflectors/skywatcher-explorer-130p-ds-eq3-pro-goto.html

I think I'm Bortle 5/6 where I am, so could be worse!

Hi DJC, before you go down the road of trying to guide for DSO imaging with the 4se. I'm just wondering if you have considered an equatorial mount with a shorter focal length faster scope? The 4SE with it's ALT Az wedged mount, and very slow long focal length optics will be incredibly challenging for any imaging other than planetary and lunar. I've learnt that it's incredibly easy to flog a dead horse with astrophotography. Been there and got the T-shirt life is easier if you use what is well documented to work for DSO imaging i.e. a good equatorial tracking mount and shorter focal length faster scope. Hope that helps

You only live once Mike! I hope you get some better nights soon to test out the DZ

I think the other frac as a bit of a cup size... er, I mean aperture advantage at least

Congrats Mike I didn't know about a 'Z' variant! How does this one differ, is it f-ratio? p.s. Can we expect a certain other frac picture soon also?

Took my boy out side last night and he was excited to see a string of them whizzing by. I said loads more of them will be launched soon and the sky will become really busy with them at which point he looked freaked out! I told him I wasn't pleased about it either. I'm pleased to see my boy getting more and more into astronomy, I just wonder what kind of sky he'll be looking at when he grows up with bright fast moving satellites cris-crossing the night sky!

I'm pretty amazed at these, nice one!

That's correct, and as you know you can't bring all wavelength of light to the same focal point with a doublet. However, it's easier to come close with high refractive index glass right? Other variables of course include aperture and focal length (focal ratio), and whether it's a doublet or triplet, and the optical figure etc because you can make a very well corrected scope with fpl51 if it's a triplet. All other things being equal, shouldn't fpl53 do a better job? The reason I'm arguing the toss is because I've always been put off cheaper fpl51 ED scopes because the reviews highlight that they are more semi apo, and the images taken with them don't look pin sharp to me. Having said this I would be happy with very smaller ED scopes having fpl51 because even very small aperture achro's show very little CA. The online aperture and focal length chart that often crops up demonstrates this.

If this is true it would save us all a lot of money! At low mag and dim object visual maybe it is true? for any kind of imaging I think FPL51 glass looks a bit more 'bloaty' to my eye.

I'll be honest with you, if you like tinkering with things then you'll be happy, but if you want something that will just work out of the box for imaging then you are likely to have to invest a bit of time and extra money. I've had a couple of f4's and found I was constantly tinkering with them trying to get them setup right. Good advice above about purchasing advanced collimation tools, my cheap laser wasn't accurate enough. Temperature changes also effect collimation with f4's which is something you need to take into account unless using a carbon fibre tube which is more stable. F5 is the sweat spot I found. Still fast but very easy to collimate compared to f4. I didn't get as far as worrying about coma with mine as I was stuck at the collimation stage, but I know some do get on with f4's and I hope you're one of them

Good mounts them AVX's considering the price.I remember Dec having a ton of friction on mine so good move with the bearings and the stripping of the 'Synta glue' as I call it. I do think AVX's do a few things better than the HEQ5 pro, but tracking performance isn't one of them sadly. I think this is partly down to the servo rather than stepper motors? If it works out well you should maybe consider post up a primer with the steps you took and parts you used? I'm sure there are a ton of AVX owners out there who would love to tweak their mounts. Lots of tweaks for the HEQ5 pro but maybe not so many for the AVX? I also tried DSO's with my AVX C8 Edge and found it a no go situation. I reckon the CGX would do well with the C8 though if you ever find 2k laying around

The 62 looks very keenly priced!

Imaging refractors tend to be shorter, optically 'faster' and very well corrected for chromatic aberration. Plus they're designed to be used with a field flattener and to have a larger circle of illumination to avoid both 'warped' stars and vignetting. Visual telescopes tend to be longer and slower as to be kinder on eye piece edge performance, and are probably more likely to be achromatic rather apochromatic as chromatic aberration isn't quite so exaggerated visually as it is by a camera sensor. Of course there is absolutely no rule which says you can't image with a visual orientated reafractor and vice versa, only if you choose the right tool for the job it of course makes things easier and the results are likely to be better.

Next time you're out under the stars, de focus a star in the centre of an eyepiece at high ish mag. If you don't see a concentric doughnut then the scope needs collimating. Here is a good guide to collimating an SCT.

Welcome back Philip 👍

Nice one! Well done to him

AP will exaggerate chromatic aberration, so if you're reasonably discerning maybe go for the Esprit out of the two mentioned. If you had said a mixture of AP and visual I would have steered you towards the WO 103 as it will cool a little quicker, it's cheaper, and for visual the CA won't be as noticeable, but for pure AP go with a triplet.

I just stumbled across Virtual NEAF 2020 whilst browsing youtube. I was going to give people the heads up when I saw your post : It seems to be live now, and the action begins at 55:34 into the video below:

Cool video. How do you prevent the roof from leaking?

I did option 2 (converted a robust shed). This was a couple of houses ago now so I've been without for years and have missed it. Now I'm permanently settled I'm gearing up for another shed conversion. This is the thread for my first build, and it would never have happened if I hadn't of asked a million questions on SGL (I'm fairly sure I drove people mad at the time )

Congrats, I look forward to hearing your thoughts! I must admit to constantly ogling the 80mm f10 to fulfil my long frac fetish