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Alt-Az Mount for double stars

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#1 JimP

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Posted 28 December 2020 - 03:55 PM

Do any of you use an alt azimuth mount for your double star viewing? Is there a problem with drift through the field of view using high power eyepieces? Do you use wide field eyepieces like Naglers or ethos eyepieces  for this reason?

 

Happy new year

 

Jim



#2 BlueMoon

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Posted 28 December 2020 - 04:07 PM

Do any of you use an alt azimuth mount for your double star viewing? Is there a problem with drift through the field of view using high power eyepieces? Do you use wide field eyepieces like Naglers or ethos eyepieces  for this reason?

 

Happy new year

 

Jim

A. Yes. Porta II alt/az on a steadier EQ-3 steel tripod.

B. Yes. It's the physics of it. Everything drifts faster regardless of what it is at higher mags.

C. No. I use a wide-field eye pieces to frame my target then increasingly higher mags to resolve it. My slo-mo controls work well on keeping the target framed. If I lose it, I back out a few mag levels to reacquire it and then pay more attention. waytogo.gif

 

Clear skies.

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  • 100_Porta_400.jpg

Edited by BlueMoon, 28 December 2020 - 06:50 PM.

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#3 John Fitzgerald

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Posted 28 December 2020 - 04:10 PM

I have used an undriven Dob and an undriven alt-az, but it's a hassle at high power for doubles, especially if you have to change eyepieces for a split of a close one.  I mostly use 62 and 70 degree eyepieces with long eye relief.   If you get a driven alt-az or an equatorial table for a Dob, then viewing doubles changes to a pleasure.


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#4 StarBurger

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Posted 28 December 2020 - 04:51 PM

I may be considered a dinosaur here but...

50 years ago the DOB mount (or indeed any alt-az mount ) was not considered a "real" mount. EQ's were the thing.

For that reason I cut my teeth on EQs and never had a problem using them. It came naturally.

After a hiatus of 45 years and the advent of DOBs I actually struggled to use one. 

Push and pull on BOTH axes at the same time? DOBSON's hole? Not intuitive. Stars shooting uncontrollably all over the field.

I'm OK with it now but when I want to do double stars or DSO's I wouldn't bother without an EQ and preferably a goto.

Just one axis to track on manually or (preferably) driven.

Set up well and aligned it really doesn't matter the EP power though low power wide field is best. Just scan around in RA and the star will show up. 

Often with a DOB I loose the field wildly and have to start again with my laser. My DOB is only for planets and the Moon.

I can star hop with the best of them, if I have to, but goto has been a game changer for me in terms of frustration and time spent.


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#5 Mike W

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Posted 28 December 2020 - 05:09 PM

Yes, TV102 with Gib. HD5.

 

5.jpg


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#6 Cotts

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Posted 28 December 2020 - 05:24 PM

5mm Nagler 82º eyepiece helps considerably....

 

Dave


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#7 CharlieB

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Posted 28 December 2020 - 06:11 PM

I use this alt-az setup for doubles.  A SB mount (which is surprisingly smooth when I take the time to balance everything) with a Celestron Omni XLT 120 and a Mayflower 76/1200.  It's always fun to compare the views of the two.  While the Celestron has a significantly larger objective, the Mayflower never fails to provide a more pleasing view.  The Mayflower can accept a 1.25" visual back, so I can use wider field eyepieces than the native .965" ones.  I don't have extreme wide field eyepieces, but I usually use a set of TMB/Burgess Planetaries and a pair of Svbony 7-21mm zooms.

 

 

3&5.JPG


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#8 spkerer

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Posted 28 December 2020 - 09:31 PM

I use an Alt-Az mount, but it tracks so no issue with drift.  I use either an Ethos or my 3-6 planetary zoom.  I love the field of view of the Ethos, but I like the zoom of the 3-6 because I can adjust zoom easily based on seeing conditions.


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#9 Jon Isaacs

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Posted 29 December 2020 - 07:14 AM

I only use manual tracked alt-az mounts.  My refractors have slow motion controls, my Newtonians are Dobs.  With the refractors, I go about 80/inch, sometimes more. Slow motion controls on a steady mount make that relatively easy.  I have a StellarVue MG-2, obsolete but steady with the NP-101 and 120mm Eon.

 

Eon Number 2 Backyard 1.jpg
 

With my Dobs, I have made some effort to make sure they track nicely at higher magnifications.  The 10 inch and the 13.1 inch are my planetary-double star scopes since they live in San Diego where the seeing is generally much better than in the high desert.  For the close doubles I use the 5mm and 3.5mm Naglers with a 2X Barlow when the seeing is on the good side.  With the 10 inch, I will go 820x, with the 13.1 inch, a little higher.

 

Starsplitter Back March 2015 CN.jpg

 

I have an equatorial platform but I just found I prefer tracking manually.  I keep my eyepieces close at hand so swapping eyepieces is not normally a problem but if I accidentally bump the scope, I have to drop down to 300x-400x and reacquire the target.

 

Jon


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#10 rugby

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Posted 29 December 2020 - 10:27 AM

Jon: which make of platform do you have.  I have come close to buying used but miss the sale by a day because  I waited too long to respond.


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#11 Tyson M

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Posted 29 December 2020 - 07:12 PM

I use a DM6 with wide field eyepieces, like 70-76 deg for sub 10mm and for enough eye relief for glasses usage.  I was using Vixen HR's (no glasses on) which gave sublime views, but that was pushing it a bit too far, pardon the pun.


Edited by Tyson M, 29 December 2020 - 07:13 PM.


#12 PJ Anway

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Posted 12 January 2021 - 10:17 AM

Because of the high powers that double-star observing often requires, I would think it would be difficult to use an alt-az mount that didn't have slow-motion controls or tracking motors.

I use an AZ-100 and it works fine.

 

TEC110 - AZ100_2.jpg

 


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#13 Sarkikos

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Posted 13 January 2021 - 02:25 PM

Do any of you use an alt azimuth mount for your double star viewing? Is there a problem with drift through the field of view using high power eyepieces? Do you use wide field eyepieces like Naglers or ethos eyepieces  for this reason?

 

Happy new year

 

Jim

Yes.

No.

Yes.

 

Mike


Edited by Sarkikos, 13 January 2021 - 02:29 PM.


#14 Sarkikos

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Posted 13 January 2021 - 02:29 PM

Because of the high powers that double-star observing often requires, I would think it would be difficult to use an alt-az mount that didn't have slow-motion controls or tracking motors.

I use an AZ-100 and it works fine.

 

attachicon.gifTEC110 - AZ100_2.jpg

I've had several mounts with manual slo-mo controls, but I never liked them.  The repetitive turning of the wrist irritates me.  That gets old real fast for me.  I'd rather push, push, push.

 

Mike



#15 Tyson M

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Posted 13 January 2021 - 02:48 PM

I've had several mounts with manual slo-mo controls, but I never liked them.  The repetitive turning of the wrist irritates me.  That gets old real fast for me.  I'd rather push, push, push.

 

Mike

I agree with this but with one caveat: the push, push is facilitated by a handle and not via the scope body/diagonal. 

 

With really long/large scopes this is not possible though. 



#16 Tyson M

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Posted 13 January 2021 - 02:49 PM

Because of the high powers that double-star observing often requires, I would think it would be difficult to use an alt-az mount that didn't have slow-motion controls or tracking motors.

I use an AZ-100 and it works fine.

 

attachicon.gifTEC110 - AZ100_2.jpg

I do think this mount is very nice though.  Love the placement of the Nexus.  Looks like a superb mount.


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#17 Sarkikos

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Posted 13 January 2021 - 02:53 PM

I agree with this but with one caveat: the push, push is facilitated by a handle and not via the scope body/diagonal. 

 

With really long/large scopes this is not possible though. 

Yes, I agree.  I like a panhandle on alt-az mounts when possible.

 

Mike


Edited by Sarkikos, 13 January 2021 - 02:53 PM.


#18 Jon Isaacs

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Posted 13 January 2021 - 06:39 PM

Jon: which make of platform do you have.  I have come close to buying used but miss the sale by a day because  I waited too long to respond.

 

Sorry for my late response.

 

I have a Tom 0. dual axis Aluminum Equatorial Platform. They're not cheap but I got an excellent package deal. The platform and my 13.1 inch Starsplitter with a Royce mirror Feathertouch focuser etc. 

 

Jstar on EQ Platform reset handle.jpg
 
(My 12.5 inch)
 
 
Jon

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#19 PJ Anway

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Posted 14 January 2021 - 09:41 AM

I've had several mounts with manual slo-mo controls, but I never liked them.  The repetitive turning of the wrist irritates me.  That gets old real fast for me.  I'd rather push, push, push.

 

Mike

That is where the AZ-100 mount is so nice. The slo-mo control on each axis has a clutch. When released you can push to your hearts content; when engaged you have slo-mo controls for keeping the stars centered.


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#20 Lola Bruce

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Posted 14 January 2021 - 04:02 PM

If I was starting over today I would by the Panther Alt/Az.  A nice TSA 120 Tak would be my choice for the frosting on top.



#21 spkerer

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Posted 14 January 2021 - 07:25 PM

If I was starting over today I would by the Panther Alt/Az.  A nice TSA 120 Tak would be my choice for the frosting on top.

That's my exact setup and I do find it quite fantastic.

 

IMG_0768_small.JPG

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#22 Sarkikos

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Posted 15 January 2021 - 07:41 AM

I use a DM6 with wide field eyepieces, like 70-76 deg for sub 10mm and for enough eye relief for glasses usage.  I was using Vixen HR's (no glasses on) which gave sublime views, but that was pushing it a bit too far, pardon the pun.

I love my DM6.  The motion is very smooth with a panhandle. 

 

The tension can be adjusted, though you have to open the head and use a wrench to do it.  Once you have it adjusted optimally, the mount is pretty stable when switching eyepieces, but not perfect. 

 

I wish there were external knobs to completely brake the motion when needed.  I think every mount should have manual brakes (detents) designed into them.  Some of the cheapest mounts have them, while some of the most expensive do not.  Makes no sense.

 

Mike


Edited by Sarkikos, 15 January 2021 - 07:42 AM.



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