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Mount for 100mm F/9 refractor

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#1 hoa101

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Posted 08 January 2013 - 10:55 AM

I currently own a 10" dob and a 100mm Skywatcher Pro, which each serve their purposes. I like to drag the SW100ED into the yard for quick views, or break out the big dob for my trips to "dark" sky sites nearby. I have a versa-go mount for the 100ED.

Lately though, the amount of vibration resulting from focusing or nudging the scope to track an object (especially at high power) is driving me crazy. Also, that is typically the scope I break out for non-astronomer guests. Then those issues are even more pronounced. I have to constantly kick people off the eyepiece in order to readjust. Guests also accidentally touch the OTA or whatever and cause many seconds of vibration, which ruins the experience a bit.

Would you all recommend one of the lighter EQ mounts? Perhaps some sort of fancier alt-az mount with gears? I need it to be light enough that lugging it out of the house for 30 minutes does not seem like a huge chore. However, I also need to minimize or eliminate vibration, either through an EQ system or with some sort of gears, etc.

So, thoughts? Thanks for the help.

#2 michael hester

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Posted 08 January 2013 - 11:01 AM

You'll need something with a little beef in it if you're sick of vibration. I'd try a Celestron CG-4. I think a Vixen Porta 2 might work too but I don't have one of those.

#3 Adam Taylor

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Posted 08 January 2013 - 02:25 PM

I had my SW100ED mounted on an Orion SkyView Pro EQ mount, which is currently on sale. A good value in my opinion. The head has a bit more mass than a CG-4, which is a plus. I was always suprised how solid this combination was, considering the length of the OTA. I didn't experience any focusing, or eye to eyecup vibration.

#4 Binojunky

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Posted 08 January 2013 - 04:05 PM

The Vixen Porta needs wooden legs, the stock extruded aluminum ones are jiggly, its not the scopes weight, its its length that causes the problem,DA.

#5 SteveG

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Posted 08 January 2013 - 04:21 PM

I use an old Vixen Polaris mount with a Celestron 9v RA drive. Very simple & light weight grab n go. Stability is very good on the Vixen wood legs.

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#6 Gary Riley

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Posted 08 January 2013 - 06:46 PM

+1 for the CG-4 mount ( with 1.75 inch dia. SST legs). Use the mount on my 4 inch f/9.8 (1000mm fl) refractor. Very, very little vibration when focusing.

Gary

#7 AlienRatDog

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Posted 08 January 2013 - 07:51 PM

CG5 works good...

#8 Pat at home

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Posted 09 January 2013 - 01:13 PM

Don't laugh too hard at my home made tripod but I have an ED100 that came on a mostly unusable AZ3. I did away with the extruded aluminium legs and replaced with fixed wooden ones. Only a tiny bit heavier but it did turn a useless mount into an enjoyable one. The altitude worm gear still has some backlash but the mount does not jiggle when focussing or slewing.

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#9 hoa101

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Posted 09 January 2013 - 01:17 PM

Thanks for the advice guys. I will look into those.

CG5 works good...


I think the CG5 does not meet my portability criteria. I also like how the "poor" student recommended the most expensive mount of the bunch. ;)

#10 dennilfloss

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Posted 09 January 2013 - 03:52 PM

Don't laugh too hard at my home made tripod but I have an ED100 that came on a mostly unusable AZ3. I did away with the extruded aluminium legs and replaced with fixed wooden ones. Only a tiny bit heavier but it did turn a useless mount into an enjoyable one. The altitude worm gear still has some backlash but the mount does not jiggle when focussing or slewing.


To me that looks very nice. Maybe add some varnish that matches the tint of your window sills and it could just remain there when not in use and totally fit the decor. :)

#11 frolinmod

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Posted 09 January 2013 - 05:42 PM

I wouldn't laugh at all. That looks excellent. Much better than the spindly tripod legs that come with most small mounts. Good job!

#12 hoa101

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Posted 09 January 2013 - 10:56 PM

Those legs would support a small automobile. Nice.

People seem to charge a premium for Vixen Polaris because they are "out-of-print" these days. For the price of a VP I could get a Skyview Pro (on sale), which seems the better deal except that it is a bit less portable.






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