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Good alt/az for 4" refractor

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#1 Nippon

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Posted 01 July 2014 - 05:09 PM

The scope is a Vixen ED 103. F/7.7 weighs about 8 pounds. I have a Porta II and even on a HAL 130 tripod it is to shaky.I would like to stay under $600 so The Disc Mount, Half Hitch and T-Rex are out.

#2 choran

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Posted 01 July 2014 - 05:49 PM

You may have good luck buying used, such as a Universal Astronomics Unistar deluxe, or a Televue Gibraltar. Used, you could swing either, and they come up periodically on this site's classified and others as well. They would satisfy you, I believe. Some go a bit old school and use a Vixen Polaris and use it in alt/az mode, but I have no personal experience with that setup.

#3 Mickey_C

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Posted 01 July 2014 - 06:55 PM

I recommend the UA Unistar deluxe. It was solid in 28 mph winds at the GCSP with a SW 120ED mounted. Enough so that it's made my short list of *cherished* equipment.

It's well within your budget.

#4 astrophile

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Posted 02 July 2014 - 04:32 AM

The other mount in that price bracket you might consider is a Stellarvue M2, will require a column for tripod clearance.

#5 karstenkoch

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Posted 02 July 2014 - 07:14 AM

ES Twilight II. I use it with my SV102ED. Solid. No shaking. In your budget. Why. Am I talking. Like. James T Kirk? Seriously, if your budget is hard and fast and you want the heaviest duty mount + tripod for less than $600, I know of no other (but someone please speak up if you do).

#6 hottr6

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Posted 02 July 2014 - 08:27 AM

The scope is a Vixen ED 103. F/7.7 weighs about 8 pounds. I have a Porta II and even on a HAL 130 tripod it is to shaky.

That is interesting. I have always thought of the Porta II as equivalent to the AT Voyager which is rock solid with my Kunming 102ED f/7. Maybe the extra inches in length makes the difference?

I dislike metal tripods, and I don't care who makes 'em. I suggest trying your rig with a wooden surveyors tripod. Oberwerk has seconds for cheap.

Someone suggested a Vixen Polaris. I have one (on wooden SP legs) and it is on the edge with my 102ED. Likely, your longer OTA will overwhelm it.

Finally, there are not too many alt-az in your price range with slo-mos which I am sure you will miss if you step up to a mount without them. It is worth trying the wooden tripod route first.

#7 joe4702

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Posted 02 July 2014 - 09:35 AM

M2 with column on CG5 2" steel tripod has been working fine for me with a 100mm f9 ED refractor. Also looked at the ES Twilight II - very nice but more than I needed.

#8 hottr6

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Posted 02 July 2014 - 10:30 AM

One more thought. You could try vibration pads under your HAL feet. Won't cost much to try, and you can flip them quickly if they don't work for you.

Question: You don't observe from a deck, do you?

#9 Nippon

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Posted 02 July 2014 - 02:37 PM

I don't observe from a deck and I have anti vibration pads. I have the older Hal 130 so I have to use a half pier to use the Porta on The Hal. I know that is part of the problem because when I use the half pier with my GP2 mount it is less steady than the GP2 directly on the Hal 130. I was looking at the ES Twilight II and it appears rather robust with a sturdy tripod. Anyone have one of those?

#10 GOLGO13

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Posted 02 July 2014 - 02:56 PM

Nippon,

I have the exact same setup as you (Porta with the 103mm F7.7). Vibration pads worked for me. But I do have wood legs vice the metal ones.

I have not tried other mounts for this scope to give a good opinion as the others have.

I do think the FTX would have been good...but over budget I know.

#11 choran

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Posted 02 July 2014 - 03:21 PM

If you can find the Unistar deluxe used, and put it on the larger of the Oberwerks wood tripods, who will be quite pleased--the vibration is almost non-existent. Last night I was out with that setup and a Televue NP101, which is about the same weight as yours or a bit heavier, and truly, tapping the mount results in a vibration that settles in 1/2 second or so. This on a concrete driveway and no anti-vibration pads.

#12 Nippon

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Posted 02 July 2014 - 06:20 PM

I'll look into the unistar. Your 101 is heavier than my Vixen. I remember from looking into the specs for your scope when looking to buy a 4 inch scope. And it is nearly as long I believe because of the petzval design. I found a vendor offering a used Stellarvue MG Deluxe head only for about $200. Anyone with some experience with the MG?

#13 izar187

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Posted 04 July 2014 - 04:13 PM

The scope is a Vixen ED 103. F/7.7 weighs about 8 pounds. I have a Porta II and even on a HAL 130 tripod it is to shaky.I would like to stay under $600 so The Disc Mount, Half Hitch and T-Rex are out.


No slow/mo controls, but how about something along these lines?
I've had success with newt ota's up to 20 lbs doing something vaguely similar.

http://www.astromart...?article_id=689

#14 bgi

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Posted 05 July 2014 - 09:59 AM

That's awesome and the way we did it way back when "old school" style aka Edmund's "All About Telescopes" by Sam Brown.

Modern day hand-grenade eyepieces makes using these more difficult with re-balancing. But the price is right and they're pretty quick to put together.

#15 vkhastro1

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Posted 05 July 2014 - 10:23 AM

The Tak Teegal with Lapides modification is a great alt-az
mount with slow motion controls on both axes.
They frequently come up for sale on the used market for around $450.00.
Add a heavy duty wooden tripod (Berlebach/William Optics versions) - again available for less than $150.00 on the used market.
Great setup and the purchase price will be around your
$600.00 budget.

#16 izar187

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Posted 05 July 2014 - 03:39 PM

That's awesome and the way we did it way back when "old school" style aka Edmund's "All About Telescopes" by Sam Brown.

Modern day hand-grenade eyepieces makes using these more difficult with re-balancing. But the price is right and they're pretty quick to put together.


They do assemble fast.

All About Telescopes oughta be on everybody's shelf!

You are certainly correct about heavy ep's, but it can be countered somewhat.
The threads are tapered, and altitude movement can be tightened up by quarter turns of the flange on the altitude threads.
Don't lap the threads, but match the altitude threads for smoothness, at the store.
Then add a wrap or so of teflon tape.
No oil, to catch grit, or to get on you or your stuff.
Just the very affordable, clean, disposable and replaceable, teflon pipe tape.
Comes in little snap shut roll containers, to store with the observing kit.

You can also hang the ota so that as it travels from zenith toward the horizon, those tapered threads are tightening up by a quarter turn.

#17 Russ S.

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Posted 07 July 2014 - 09:27 PM

At your weight you could use one of UA's mounts smaller and cheaper than the Unistar which is rated for 30-40 lbs. The owner Larry is suppose ro be very friendly and helpful, I'd definitely give hima call.

#18 lamplight

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Posted 08 July 2014 - 07:27 AM

Stellarvue MG Deluxe head only for about $200. Anyone with some experience with the MG?


I bought a used one about a year ago, works excellent on my 120mm f/7.5. i usually don't use the slo mo controls (awkwardly placed, although extensions are available I've read). if i balance the scope properly it moves with a gentle nudge like a dob(i leave the clutches disengaged). there are some mixed reviews if you look around (they seem to vary depending on scope size/weight) but I'm very happy with mine.

i also had metal tripod leg vibration issues, replaced the inner extension legs with wood and it fixed all my vibration problems. down to about 1-2 secs under high magnification. the mounts solid, just needs a good wood tripod.

btw i also did see some universal astronomics stuff in the classifieds recently.

#19 Pat at home

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Posted 08 July 2014 - 07:38 PM

I often mount my ED100 on a cheap Skywatcher AZ-3 on which I've replaced the spindly bent aluminium legs with DIY wooden ones. Turned a barely useable setup into a very nice one.

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#20 bicparker

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Posted 08 July 2014 - 10:36 PM

Porta II with HAL130 tripod with my 100mm SW Esprit triplet (f/5.5). I use the train-n-track option which makes vibrations much less of an issue and also gives some reasonable tracking within a relevant range of time.

The short focal ratio of this scope really makes the Porta II viable for this setup. The HAL130 tripod, in my opinion, should be the standard tripod for this rig. The basic one that they normally sell with the Porta II is very inadequate and reduces the actual capabilities of the mount head.

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#21 M44

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Posted 08 July 2014 - 11:22 PM

+1 on Tak Teegal. I have used everything on the market. This is the best mount when combined with a decent tripod.

#22 terraclarke

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Posted 09 July 2014 - 08:11 PM

I too recommend the UA Unistar Deluxe. It handles my 4" F15 just fine. It's smooth and rock steady.

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#23 Rachal

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Posted 10 July 2014 - 09:45 PM

Terra, About how much does the mount and the tripod weigh together, minus the OTA? Thanks.

#24 Nippon

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Posted 11 July 2014 - 12:32 PM

I'm impressed that the mount can handle a scope as long as a 4"f/15. That is what like a 60" tube plus dew shield. Couple that to a tall tripod to see near the zenith. Impressive indeed.

#25 Nippon

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Posted 12 July 2014 - 01:59 PM

I ordered the used Stellarvue MG Deluxe. I believe I can cobble a solid wood mount for it from an old wood set of Vixen / Celestron legs. For $200 I just could not resist and if my plan to modify the old Vixen legs works out I'm done and $400 under budget. Thanks for all the information it helped me make an educated choice.






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