Which mount for imaging

[ChrisV (Chris)]

I've been doing live viewing/video astronomy/electronically assisted astronomy using my cameras (ASI224MC, Canon 450/550 modded). To do this I'm stacking 5sec - 1min subs in sharpcap live. My old CG5 goto mount is okay for that - using an 80mm APO, or an 8" SCT (with focal reduction).

But I'd like to try some imaging, so have been doing longer subs 2 - 10 min with guiding - using my 80mm APO with an ST80 guiding. As you can imagine my mount isn't quite up to that.

So what sort of mount might I look at ??
I'd been considering an NEQ6, but have seen that Bintel is selling off the Celestron CGEMs which makes it ~$500 less than a new NEQ6.

Any advice ??
Thanks, Chris

[glend (Glen)]

That is not a bad price for the Celestron CGEM. You should consider the imaging weight of your scope/camera/filter wheel setup and use that number to frame your decision. Ideally you want to keep your combined load to around 50-66% of the stated mount capacity, unless a manufacturer publishes an imaging capacity. Most publish the visual capacity. You will need a mount with a guide port, and the CGEM has that. It also has Any-star alignment which is a nice feature.

[ChrisV (Chris)]

Thanks Glen. My current scope loaded with guidescope cameras etc is 7.5kg. But I was thinking of the possibility of an 8-10 imaging newt some time. This would be an extra ~5 kg. So that puts under 50-60% of payload for both the CGEM and NEQ6.

Very tempted by the CGEM. On sale, as being replaced by the CGEM II which doesn't sound any different except for a USB connection etc.

So it seems like very similar to the NEQ6. But the skywatcher has the possibility for belt mod etc, which sounds great.

[traveller (Bo)]

Chris, if you intend to upgrade scopes later, I suggest you go for the AZEQ6.
Belt drive, digital encoders and still portable.
I have a belt modded EQ6 but need to extend the counterweight shaft and add a counter weight when I mount my 10" newt tube, as it was approaching the mount's instrument capacity limit.
A solid mount is essential for AP work, so don't skimp there, it's just false economy as you may need to pay more in the long run.
cheers
Bo

[glend (Glen)]

I believe the AZEQ6 and the NEQ6 PRO have the same imaging capacity. Skywatcher pulled a marketing trick recently to try and differentiate the NEQ6 R from the NEQ6 Pro, by lowering the advertised capacity to 18kg on the standard model, same for the AZEQ6. They really all have the same imaging capacity. Bintel still show them as the same 20kg capacity on their website. The rule says about 15kg max for imaging payload on the EQ6 or AZEQ6, so a 10" steel tube newt would be marginal. I have a 10" carbon strut newt that i built specifically to get under 15kg loaded with imaging gear. An 8" would be fine. Having it on a pier helps alot for imaging imho. If you consider the imaging capacity of the new Celestron CGX (25kg), then it is better than the Skywatchers, and that's the niche Celestron is aiming to fill. The CGX is belt driven as well, but not available locally for a few months and it will be around $4000 AUD minimum. In the sub $2000 price range it is hard to ignore the NEQ6 Pro. But as the saying goes "buy the best mount you can afford".

[ChrisV (Chris)]

Thanks for the info guys. AZEQ6 is beyond my budget anyway.
Now looking at the CGEM (new) or NEQ6 (2nd hand).

[Camelopardalis (Dunk)]

Especially at that price, you can't go far wrong with the CGEM. It's a solidly built mount, and as it's been around a few years it's quirks and flaws are well documented. It should guide perfectly well with C8 on board. From a visual point of view, I prefer the Celestron hand controller software to the SW Synscan.

IMO the build quality of the Celestron mounts is just a touch above the Skywatchers. That's not to say they don't have some bits of cheap plastic, but I have an AVX that I've never been compelled to upgrade, the adjustment bolds are large and easier to use for example, whereas my workhorse EQ6 is a bit of a franken-mount at this point of course, it's a little unreasonable but I demand more from my EQ6 because of its load carrying capacity.

[ChrisV (Chris)]

Bit the bullet and got the CGEM from Bintel the other day. Heavier than my old CG5-GT but doesn't seem unmanageable. Its a lot quieter too.
Tonight's lookin good ...

[Camelopardalis (Dunk)]

Good luck Chris keep us posted!

[ChrisV (Chris)]

Setup in the CGEM mount backyard last night. First problem, it was binding, getting stuck in a few spots on the DEC axis. Groan, Celestron quality control. Anyway, it was a bit cloudy early on, so I adjusted the worm gear tightness
http://www.cloudynights.com/topic/27...rm-adjustment/

Was fine after that (might need to fine tune that a bit more today). It finally cleared up, so did the star alignment, then polar alignment. Compared to my old mount - bang on target and tracking nicely on my 8" SCT (at ~F5) with ASI224MC camera. Attached pic of NGC3132, live stacked 8x16sec in sharpcap.

I'll have to sort out guiding (and focusing and ...) and have a go with my refractor/dslr next. This mount might be old hat to most out there, but for me WOW !!

[Camelopardalis (Dunk)]