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Advice with Alt Az mount for grab n go telescope (SCT5")


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Hello everyone,

Few days ago I was given the advice from a member to use a small grab n go telescope to increase my observing time. I own a small SCT (a Celestron 127 XLT, click here) and I would like to mount it with an AltAZ mount so the whole set up is as light and portable as possible. I have made some research but maybe some of you has gone through something similar in the past.  Some extra info / questions:

  1. OTA weights 3 Kg
  2. Can I put this on top of a video camera tripod? Or is it too risky? Is there an adaptor in the market for the dovetail or do I need to make one?
  3. Can I use the legs of the CG4 mount?
  4. Wooden legs would me most welcomed, but I would welcome all posibilities

Thank you very much for your input!

Caput

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Personally I would avoid a photographic tripod, you'd have to seem quite a bit to get one stable enough imho. I would suggest an AZ3 provided your bar has the facility to screw a bolt into it. I use this for solar obs with a PST.

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I'm not sure how portable it has to be, but if you're considering using the CG4 tripod anyway, have you thought of just using your EQ mount in pseudo-alt/az mode, perhaps for a while, just to get a taste?

I seem to recall that you are a Dob user; is an SCT going to significantly reduce your setup time (cooling)? Just asking, as I only have experience with small refractors.

The suitability of your video tripod in combination with its "head" will depend on the weight it's rated to carry. I have used a sturdy camera tripod with some success, but prefer an astro tripod in most cases paired with a Giro Ercole Mini mount (head).

However, if you REALLY want to increase your observing time, how about a nice pair of binoculars?

:happy11:

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My C8 has a screw thread on the dovetail which fits a phtotgraphic tripod screw (3/8"?), so you may want to check yours. The problem with mount directly onto a tripod is that the scope becomes unbalanced the closer you point to the zentih and for a scope of your size is not really an option imo. As ipeace suggests would definitley propose putting something like a Giro Ercole mini on top of a decent tripod, I would think your CG4 tripod could be made to fit. You need as much stability as possible with your scope as you will probably be wanting to make use of its longer focal length to get some higher mags. 

My grab and go setup is a 72mm refractor on a photo tripod with a homemade head conversion ( which i plan to upgrade to a giro mini). No cooldown required, no dewing problems and no collimation required. Very quick to set up and easy to use. :) 

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First of all, thank you for the advice. As always, very good answers.

6 hours ago, Gazabone said:

Personally I would avoid a photographic tripod, you'd have to seem quite a bit to get one stable enough imho. I would suggest an AZ3 provided your bar has the facility to screw a bolt into it. I use this for solar obs with a PST.

OK, thanks. It was a longshot just in case someone was using that set up. Photographic tripod ruled out.

5 hours ago, iPeace said:

I'm not sure how portable it has to be, but if you're considering using the CG4 tripod anyway, have you thought of just using your EQ mount in pseudo-alt/az mode, perhaps for a while, just to get a taste?

Using the CG4 tripod was just a possibility, trying to use what I already got. For me portable will mean that the OTA will be at home and the rest of the gear will be at my van, so all I need to do is getting the OTA and a couple of EP to the van an off I go to my semi-dark place. 

 Now I am intrigued about teh pseudo alt/az mode. Can you ellaborate more? Or is it the Giro Ercole mentioned below? 

5 hours ago, iPeace said:

However, if you REALLY want to increase your observing time, how about a nice pair of binoculars?

I have a pair of binoculars, regrettably binoculars are not my cup of tea. 

4 hours ago, RobertI said:

As ipeace suggests would definitley propose putting something like a Giro Ercole mini on top of a decent tripod, I would think your CG4 tripod could be made to fit. You need as much stability as possible with your scope as you will probably be wanting to make use of its longer focal length to get some higher mags. 

My grab and go setup is a 72mm refractor on a photo tripod with a homemade head conversion ( which i plan to upgrade to a giro mini). No cooldown required, no dewing problems and no collimation required. Very quick to set up and easy to use. :) 

Thank you for the heads up I will research this Giro Ercole. It seems like a nice piece of gear. 

So I have now some homework to do, at least is pointed in a good direction. I will research the Giro Ercole and AZ3 type of mounts.

Thanks again! :smiley:

Caput

 

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6 hours ago, iPeace said:

have you thought of just using your EQ mount in pseudo-alt/az mode, perhaps for a while, just to get a taste?

Hang on. After checking the web I think I got it. I need to put the latitude setting of my EQ mount to 90º and then the RA and Dec movements become Alt Az. How neat! I will give it a go so I can check overall performace and balance.

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Using an EQ mount in alt/az mode basically means (to me) setting up the mount so that the azimuth axis rotates level to the ground on which you stand (or as close as you can get). You then use it as you would use a Giro Ercole. Forgive me if I'm overlooking something with this idea, it's merely something I know others to have done.

:happy11:

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Just now, Caput Gorgonis said:

Hang on. After checking the web I think I got it. I need to put the latitude setting of my EQ mount to 90º and then the RA and Dec movements become Alt Az. How neat! I will give it a go so I can check overall performace and balance.

Just what I was trying to get typed!

:icon_biggrin:

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It is still not that light weight though for travelling around.  Don't dismiss a photo tripod and video head - as long as it's a sturdy one.  These  C5s  are often sold as a spotting scope package, and used in this way. Worth investigating, especially if you are going to use it for low power deep sky.

 

andrew

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1 hour ago, andrew63 said:

It is still not that light weight though for travelling around.  Don't dismiss a photo tripod and video head - as long as it's a sturdy one.  These  C5s  are often sold as a spotting scope package, and used in this way. Worth investigating, especially if you are going to use it for low power deep sky.

 

andrew

Well I hope a video head is better than the pan head of my heavy duty photo tripod.

I'm down to using a C6 on this tripod and it's blimming horrible to use. Any thing above 30 degrees is dangerous, but above all trying to find an object and locking everything down so it stays on said object is difficult to say the least. Tracking is very difficult/tedious/jerky

I would favour slow motion controls when using a long focal length scope. The CG4 in seudo Alt/az mode sounds like it's definaley worth a go.

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I had a C5 mounted on an AZ-3 for a while. The mount coped pretty well with the short tubed scope and the slow motion controls were helpful. Probably about as portable a 5" scope setup as you can get while still having some decent stability.

 

c5az201.jpg

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Thanks everyone for your replies.

John, that seems a pretty straight foward set up. Thanks for the picture.

18 minutes ago, Pig said:

What about something like this ?

Pig, is that one of those Giro Ercole type of things? If so, a couple questions if you do not mind:

  1. Can be used with one telescope or they balance each other?
  2. How do you move the OTA? Just moving it? Or are there slow motion controls somewhere?

Thank you in advance!

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The one in the picture is the Ercoles little brother, it is not the mini giro. It is a WR giro IE water proof and even with the tripod it is very portable. All 3 are made by the same company. 

You can use them with a single scope as long as it isn't over heavy or you can put a counter weight on the other to match the scope.

They are very smooth mounts and are moved by hand

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giro-ercole-mini_20160409.JPG

Here's my Giro Ercole Mini. You can attach a dovetail clamp to either side or to both sides; one side will take a counterweight bar as shown. There are no motion controls; the knobs are for adjusting the tension on either axis. So it's a matter of balancing the scope and getting the tension right; after that you just move the scope as desired. Keep in mind that changing eyepieces etc. may require balance and / or tension adjustment; took me some getting used to but I'm quite happy with it now. Probably as close to a "dob experience" as one can get without using an actual dob...

:happy11:

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