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Alt-Az Mount for 4" f10 refractor

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#1 csrlice12

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Posted 21 October 2013 - 02:59 PM

Hey all, I'm mount stupid when it comes to alt/az mounts. I have a 102XLT on a CG4 EQ mount, but would like to find a useable, but inexpensive Alt/Az mount for GrabnGo. As the CG4 is motorized, I don't want to use it in alt/az mode. The OTA weighs about 10lbs, and I have some heavier eyepieces and the RACI. I want it to use in the back yard for lunar/planetary use only. No AP, just visual. I'm looking for a mount/tripod under $200, used would be fine...any ideas? :help:

#2 Bill McNeal

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Posted 21 October 2013 - 05:25 PM

Celestron has two alt-az mounts, each less than $100. The Astromaster (item 93610) and 93607, which has slow-mo controls. I haven't personally tried either, but they may be suitable for you.

#3 dennilfloss

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Posted 21 October 2013 - 07:43 PM

If slow-motion controls aren't important to you, I'd recommend the Skywatcher AZ4 with steel legs.

#4 brokenwave

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Posted 21 October 2013 - 07:52 PM

If you could spent $300 the Explorer Scientific TwilightI,
is hard to beat, Orion has a similar style mount for $329.
IMHO these are more stable than a Vixen Porta II,
I have compared the Porta II to the TwilightI and it was 5 second vs 2.5 second settling. With the ES Twilight the winner.
Since your 102 is 40" long having a good tripod is a must to handle the leverage from a longer scope.


#5 mayidunk

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Posted 22 October 2013 - 02:03 PM

I use a William Optics Easy Touch ALT-AZ mount on an Oberwerk wooden tripod. I am able to mount an ES AR-152 refractor on it, using the counter weight shaft from an EQ-2 mount to hold the counter weights needed to balance its 24 Lb. weight. However, it should handle your tube without needing a counter weight. They're no longer being made by WO, but can be found used. Here is William Optics web page for this mount, it contains useful information. Here's the link to Oberwerk's clearance page. Page down one page to see the blem wooden tripods they're currently selling.

#6 edwinh

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Posted 22 October 2013 - 02:59 PM

Do you need slow-mo? If not and you already have a tripod, could get something like a stellarvue M2 head. Show up used occasionally for around your price point. I have my C102 on the M2 (until the planned dsv-2 shows up!).... works well for me.

#7 *skyguy*

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Posted 23 October 2013 - 05:32 AM

You could always look around for a used Vixen Polaris mount and set it up in alt-az mode. It has slo-mo knobs on stalks on both axes and the quality of this mount is superb ... a real joy to use! Around $125-$175 should get you one in very good used condition.

#8 hottr6

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Posted 23 October 2013 - 07:55 AM

Not for a 4" f/10. No way. No how. The Polaris may be happy with the weight of the OP's OTA, but not with that long tube. My 90mm f/11 is a mess on the Polaris at exit pupils of 5mm and smaller. Does not bode well for planetary work.

IMHO, you will need something that is equivalent to a Vixen GP, or larger. AFAIK, there are no alt-az's with this capacity, in your price range...... except Richard Berry's roll-your-own alt-az. No slo-mo, however.

Good luck. Long 'scopes are a lot harder to mount.

#9 csrlice12

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Posted 23 October 2013 - 09:05 AM

Wow, a lot of responses. I would like slo-mo controls. In fact, the only reason I was looking is that the CG4 EQ is motorized and for quick grabngo is just not the mount of choice. I could use it in alt/az config, but then theres the mess of setting it back up into EQ mode, polar scope alignment, and that I don't want my grabngo motorized, etc.... I suppose I could get a second used CG4 and convert it to alt/az...just thought there might be one out there at a reasonable price already. Seems they're no cheaper then the EQ mounts.






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