What EQ mount for SCT C8 and 120mm frac OTAs?

[Amaranthus]

I currently have a Celestron C8 on a single fork mount and a SW120 on an AZ3 - both are fine for visual work. However, I'd like to start mucking about with astrophotography using these two OTAs, with the medium-term goal of buying a decent (pricey) astrograph and getting serious once I have the basics sorted out and confidence builds. Having been a visual observer all my life (apart from some planetary webcam vids), I realise I need to take some baby steps before getting seriously into AP...

So, my question is, what would be a good 'future proof' EQ mount for me? That is, something that could readily handle either the C8 (~6 kg weight) or the SW120 (~5 kg) OTAs right now, but would offer a stable enough platform with good PEC etc. that could also be a suitable mount for a future high-quality 4-6" APO or maybe an 8-10" fast newt? Ideally under $2.5K...

I've been thinking about the Sky-Watcher AZ-EQ6 GT Mount but maybe a NEQ6 is sufficient? Or other options? Cheers!

[Merlin66]

Although a HEQ5pro would probably meet your immediate needs, I'd go for a NEQ6pro - bang per buck they do a great job.

I have almost 18Kg hanging on mine - no issues, no drama.

[glend]

Barry I just ordered a NEQ6 today from Andrews. I figured my 127mm 1500mm fl refractor needed the stability of the heavy mount, and I will be starting some imaging as well. I considered the HEQ5 and the iEQ45.

[Amaranthus]

Thanks, yep - I figure that a heavier mount is worth the extra $$ for stability and future proofing -- and besides, I'm a strong and still relatively young-and-fit lad, so no issues in moving it around.

I'm strongly tempted by the AZ-EQ6 GT because it will also be a terrific visual platform that would allow me to mount by C8 and 120'frac simultaneously when doing visual. I noted this example:
http://www.astroshop.com.au/guides/sky-watcher-azeq6gt.asp

I guess I'd have to buy an additional mounting plate for that -- I assume it only comes with the one in the box.

But I'm definitely still open to other advice -- experience by users trumps hype.

[killswitch]

It comes with both saddles in the box. Also the AZ-EQ is belt driven and has dual encoders.

[Amaranthus]

The dual encoder feature is nice - so it allows push-to without getting out of alignment, right? Does the belt drive improve tracking accuracy, or just slewing speed/quietness?

[brian nordstrom]

:) I have a C9.25 on a HEQ5 and it holds it easily , but if you can afford it the AZ EQ6 GT is a very nice mount .
Here is mine so you can get an idea of the size's and as you know the C8 is a bit smaller physically and the C9.25's longer body wise .

Brian.

[glend]

You can get belt drive kits for the NEQ6, but I don't know what the benefits are at this point.

[Camelopardalis]

Go with the AZ if budget allows...I have the EQ6 but wish I had the option for alt-az operation for visual, it's much more comfortable :sadeyes:

[Amaranthus]

That's what I was thinking Dunk - the diags would always be the right way up! And it's only a couple of hundred extra bucks, which in the bigger scheme of things is nothing. Plus the belt drive...

[Camelopardalis]

Worth it IMO

[killswitch]

Yes you can de-clutch anytime and slew yourself if you dont like waiting. Belt drive reduces backlash and it doesnt have the coffee grinder noise.

Dunk let me try on his C8 at IISAC, too bad it was clouded out that night. It balanced quite well after several adjustments.

[Amaranthus]

Thanks Ed, great pic - that is just how I imagine mounting my two scopes when in alt-az mode! One follow-on question - when dual mounted like that, is it possible to get both scopes aligned to the same azimuth bearing? If they were parallel, it seems that one would be somewhat misaligned...

[killswitch]

Yes while there is an adjuster for Altitude, there is none for azimuth.

I havent figured out a solution myself since i dont own two scopes yet. Although on the Skywatcher dovetail i noticed there are cone error adjusters, which could theoretically adjust Azimuth (since the dovetail will be facing sideways)

[traveller]

Hi Barry,
You can always do a side by side or piggyback mount on an EQ mount.
I am about to piggy back my ED80 on my C8 on an EQ6. I will post a photo up by the weekend once I have it set up.
Bo

[Amaranthus]

I'm thinking my SW120 might be too heavy to piggyback on my C8 OTA, unless I but a new tube mounting. I'll see if I can work out an AZ solution.

Checking the manual online (pg 11), this was not really helpful:


Maybe Cloudy Nights will have an answer!

[Merlin66]

Barry,
I had a 6"f4 Cometracker and an ED80 sitting side by side on a dual bar on a HEQ5Pro....
To get the X-Y alignment I used a mixture of the SW cone error screws on the dovetails and aluminium shims (dovetail to saddle). Worked very well.
(I used the same system on a solar set-up - SM60/ED80 and a TS102/ Baader Herschel wedge on the NEQ6pro)
The ADM dual bars are CNC machined and give accurate alignment to the dovetails - but the optical axis may be "out" relative to the dovetails....

[ian fry]

Hi

got some photos of the AZ-EQ6 with a the 8inch sct and a 4inch refractor .

[Amaranthus]

Great Ian! But could you get them simultaneous pointing at the same object? (i.e. azimuth synced) that is my biggest concern ATM

[ian fry]

Yeah , just need to get them both level and then use the fine adjustment on the saddle that has the refractor on. It's fine for visual but i would not put anything longer than a f9 refractor on that side.

[killswitch]

That only adjusts the altitude though, it doesnt adjust the azimuth so that both scopes point at the exact same thing.

[Camelopardalis]

Surely this would be less of a problem for the wider field scope? I mean, if there is much flex in the counterweight bar (hopefully not), then getting an object in the FOV of the wider field scope should be relatively easy within a margin of error, once the object is in the FOV of the narrow FOV scope? Maybe not perfect, but a 120mm f/5 has about 3x the FOV of the 8" SCT.

[traveller]

This is my latest setup with C8 on EQ6 mounted on a D plate. I then used ADM mini clamps to clamp onto the Vixen bar on the C8 and bolted the ED80 on top (M6 25mm).
The plan (hopefully) is to use both (visual and unguided AP). I also got some guidescope rings from Ken (Merlin) as backup if I want to guide with either scope.
I had to add a 1.25kg weight between the two supplied counterweights as it was getting top heavy.
Bo