Which Altaz Mount?

[johnfosteruk]

So after an absolutely awful night out last night I've made a decision. I need an AltAz mount for observing. Excuse my thinking out loud from here on, I know I could probably find everything I need to know browsing the forums but I'm not in the mood for research today 

Last night saw the return of Labyrinthitis which causes the most astonishing and disorienting attacks of vertigo. I had it about a month ago, took some pills as prescribed and it went, happy days. The reason this is a problem as that even looking up a couple of degrees to start eyeballing the sky to locate targets sends you spinning. Don't even mention getting stuck in with the finder. It passes but is very very uncomfortable and seems to be triggered by most of the various contortions required by the use of an Equatorial mount. It really stopped me from being able to observe anything, I couldn't focus at the EP, it was all a bit of a strain so I retired indoors after a short time.

I'm concerned this may end up being a long term thing (back to the doc this afternoon) but even if not, it's got me to thinking, I love the Equatorial mount and I do intend to upgrade to something more substantial in time like an HEQ5 for imaging, most likely with a more suitable OTA to boot, however I need another way to observe - I do love observing and there's so much more to see!!

The finder problem I think will be overcome with the use of a right angle optical finder, but if I can sit while observing I can relax and the whole thing becomes less of a problem - with an Equatorial I can't do that without loosening the rings after a significant change of position which is (a) a PITA, (b) affects the balance of the scope and (c) takes valuable observing time. Now that I'm thinking about this as far as I'm concerned this is important even without the vertigo.

Also an AltAz is a better grab and go solution, either in terms of a quick setup at home when there's a break in our great British clouds, and also for setting up at a dark site. When the time comes, I'd like to setup an HEQ5 or similar on a permanent pier for imaging and have the grab and go for observing. Observing is definitely the priority first of all though, I've read Steve's bible and it's left me with a lot of questions I need to answer about equipment choices, imaging location etc. I think they'll take a while to deal with!

That's the thinking out loud done, so I have some requirements/questions/thoughts:

• My OTA weighs approx 8lb, plus EP. I don't think I'll ever own anything huge like the monster Televues but do anticipate purchasing some new EPs soon. Any new EPs will be at least slightly more substantial than the 10 & 25mm supplied Skywatcher EPs I have. 
• It would be nice to have more weight capacity in case of OTA upgrades, but not essential.
• As I said there'll be no imaging happening with this apart from the odd bodged planetary or lunar affair with a webcam for fun, this is not heavy. Looking at the images taken with dobs in the lunar and planetary sections of the forum I don't think field rotation is going to be too difficult to overcome for this.
• Goto is a must, with dual encoders so I can manually assist to speed things up when slewing and save motor/gear wear. Also, I do like star hopping.
• An alignment routine is a must, If I want to just click and go it must be accurate.
• ASCOM is a must, I might use a handset on occasion though.
• Cost needn't be an issue but obviously the lower the better.
• I'm happy with my OTA for now, the mounting rings are joined by a bar that bolts onto the EQ2 mount's 'saddle', said bar is 40mm (approx 1.5") wide, the saddles on most of the AltAz mounts I've been looking at seem to be a lot wider in the images - am I wrong or will I need a new plate/bar for mounting?

So, suggestions, comments, recommendations please oh wonderful residents of SGL land.

 

Thanks all,

Clear Skies

[Cornelius Varley]

Skywatcher Star Discovery AZ goto

[happy-kat]

Another vote for the star discovery mount. It also has benefit of freedom find which basically means you can move it with your hands if you want to and if aligned carries on tracking. And it manages 30 second imaging as a member is proving. If you are sitting to observe a refractor is much more attuned to this position then a reflector I find.

[DRT]

If cost really isn't an issue you could consider either an AZ-EQ5 or AZ-EQ6. You would then have the best of both worlds in that you could use it in Alt-Az mode for what you want to do now but switch to EQ mode when you want to image.

I just bought an AZ-EQ6 and is it quite simply brilliant. I suspect the AZ-EQ5 would cope with your needs if you don't upgrade to heavier kit.

[johnfosteruk]

I was thinking about a refractor happy-lat, but at the mo I think the mount is priority.

With regards to sitting, thinking about it now even if I choose to stand it'll be 'easier' because I'll set the OTA with the EP pointing up, and then I'm just looking down into the EP. That will be the case whatever I'm observing apart from a change of angle of course but critically you're just looking down.

I'm reading that the Star Discovery will take 5kg, so if I do acquire a right angled finder that just just about be inside the limit so that's good

Derek, it's an option, but for imaging I probably will be needing more payload capacity so I'd need the 6 not the 5 which is a little out of my price range right now (I wasn't thinking of these mounts when I mentioned cost not being an issue.) Saying that though with the short hours of darkness atm I could just wait and save, it's not like I'm missing much!

[DRT]

John,

I bought mine new two weeks ago from RVO. Since then I have seen two nearly new ones going through ABS UK for around £850, which is £450 lower than what I paid. 

I think a good second hand example of one of these is definitely worth considering over a new but less capable mount. 

[johnfosteruk]

Fair comment. Definitely worth thinking about. 

[John]

I made the decision to stick with alt-az mounts quite a few years back but I use manual ones so things like the AZ-4, my current Giro II and the alt-az dobsonian mount that my 12" newt tube is mounted on.

I've no aspirations to image so I can manage with no-tech / no-power mounts.