Sky-Watcher Star Discovery AZ GoTo Mount - Experiences

Introduction | Accessories | Mount Combined with Different Telescope Tubes | Preliminary Conclusions | Links

On this page, I present (and will present) some experiences with my new AZ GoTo mount (since July 2016). It has the long name Sky-Watcher Star Discovery AZ GoTo Telescope Mount and thus, is an azimuthal mount. I use the Sky-Watcher Heritage 100P and P130 telescope tubes and the Skymax-102 OTA on this mount - and respectively will present my experiences with respect to all three telescope tubes over time.

See also: Sky-Watcher Star Discovery AZ GoTo Mount Information - Sky-Watcher Star Discovery AZ GoTo Mount - General Experiences and Thoughts

 

Introduction

After my unsuccessful experiment with a Sky-Watcher Virtuoso mount, I looked for an alternative, which would also allow to automatically track sky objects. On the advice of a dealer, I decided to go for a GoTo-mount, where motor tracking is "automatically" included in the package. The recommended azimuthal mount, a Sky-Watcher Star Discovery AZ GoTo telescope mount, also can carry more weight than the Virtuoso mount. So far, I have not been able to use the mount a lot, but I have already used it with all the three small telescope tubes that I own: the Heritage 100P, the Skymax-102 OTA and the Heritage P130 (all from Sky-Watcher). I bought some accessories to make life easier for me; this is described in the Accessories section below.

Mount from one side

Mount turned around

Ditto with external power supply (Sky-Watcher Power Tank 12 V / 7 Ah)

Because of the few experiences gained so far, this page is only the beginning and will hopefully grow in the course of time.

First Comments

No Built-in Circular Level, no Possibility of Alignment

While similar Sky-Watcher GoTo mounts are provided with a built-in circular level, neither the tripod nor the mount itself has any such alignment aid, although this would be very helpful. One can certainly argue about the usefulness of such a circular level, but it should at least be possible to place an external circular or other level on the device, in order to be able to align it horizontally. However, in the design of the mount, there are no planar surfaces on which the level might be placed. For the tripod, this would be possible, but because the mount must be screwed onto the tripod, I would never be sure that such an alignment will be maintained after the addition of the mount. In addition, I mostly leave the mount on the tripod for convenience reasons. Perhaps, the accessory tray (eyepiece holder) might be used for alignment, but I would not be sure that it indeed reflects the correct alignment...

The control unit of the mount does not have any planar surfaces on which you might place a level

The base is completely uneven...

You might place a level on the tripod head - but only before you screw the control unit on it...

 

...or perhaps on the accessory tray?

 

It does not look quite even, though

Here, the level is not fully OK...

...but here it is. So which one is correct?

 

Accessories

As "major" accessories, I purchased an external power supply (Sky-Watcher 12V / 7Ah Power Tank) in order not to have to buy batteries all the time, and a SkyWire device made by Southern Stars (version with Lightning connector for newer iPads and iPhones). The latter allows you to command the GoTo mount instead of using the hand box with the iPad astronomy app SkySafari Pro. For this purpose, it has to be connected to the RS232 interface of the hand box. I also acquired a crosshair eyepiece (12.5 mm focal length, illuminated) for better alignment and a LED red + white flashlight with adjustable brightness to be able to read star catalogs, etc. All in all, it soon turned out that the mount was not the only investment necessary to enter the world of GoTo...

The 12 V cable for charging via car battery and for supplying the GoTo mount is stored in a timber (with caption); initially, I thought it would be missing (in the instructions it is listed, but not where it is ...)

Southern Stars SkyWire Serial Accessory

Ditto connected to iPad and hand box

Ditto, detail

Package content, batteries already installed in the illumination device

Illumination device with batteries and brightness control / on/off switch screwed in

Double cross hairs, illuminated

Flashlight with box, side view

On the top you can see the red-white switch (left) and the control for setting brightness and turning the light on or off (center)

Red light

Some Comments

Power Tank

After two days or so of observing, the first set of batteries (8 batteries) was exhausted. Thus, it soon became clear to me that I needed some power source other than batteries for the GoTo mount. If I would use the mount only at home, a 15 V power supply would be a potential solution, but since I plan to also use the mount outside in the landscape, a portable solution was required. The car battery might be used, but I may not use always use the car in such cases. I therefore decided to acquire a portable Sky-Watcher Power Tank. Overall, it seems quite OK to me, but since it has a lead battery, charge times are rather long. The device is also quite heavy, thus carrying the equipment on your back on the way to an observation location may not be a good idea...

SkyWire Serial Accessory

I used this device only for a few times up to now. It allows you to control the mount with an iPad and the SkySafari software application. This is much more intuitive than using the mount's hand control and also reduces handling errors, as I found out (I have some difficulties with the handbox...). Another good point is that you can correct the mount's positioning to a certain degree, that is, as long as the target is not too far off in the viewfinder and on the sky map in SkySafari from the real target. In this case, I was able to iteratively correct or adapt the mounts target location as to the true target location so that I did not need to perform a new two-star alignment.

It is, of course, somewhat inconvenient that the SkyWire device needs a cable connection to the iPad, especially since you can stumble easily over cables in the dark... Wireless is definitely more comfortable, but it was too expensive for me.

Illuminated Cross Hair Eyepiece

For two-star alignment you have to center two stars in the eyepiece, one after he other. But it is somewhat difficult for me, to recognize when a star is exactly at the center of an eyepiece. I therefore acquired an illuminated cross hair eyepiece - illuminated because you cannot see the cross hair in the dark. My eyepiece has, however, a focal length of only 12.5 mm, which is rather short and already leads to fairly high magnifications for two of my telescope tubes. This makes aligning the mount hard, particularly for the P130 and much more so for the Skymax-102, where the eyepiece already leads to a magnification of about 100 x (50 x for the P130). After some frustrating evenings, I resorted to using my 32 mm eyepiece, which allows for slower movements of the stars in the eyepiece. But I will have to give the cross hair eyepiece further tries...

LED red + white Flashlight

When searching for deep sky objects, you need to have more equipment as usual at your disposal and you also need to have sky maps and books available for finding out where to look (a little less with a GoTo mount, though...). Nonetheless, a red flashlight is a useful addition, particularly if you can also switch to white light when needed. The only gripe that I have with this flashlight is that I find the red light too low at times. But I read that you can already spoil your dark adaptation with red light that is too strong...

 

Mount Combined with Different Telescope Tubes

For more photos see page Sky-Watcher Star Discovery AZ GoTo Mount Information.

Mount with Heritage 100P Telescope Tube (and with SkyWire GoTo Control via iPad)

Heritage 100P tube on mount (overall view)

Heritage 100P tube on mount, turned around (overall view)

Heritage 100P tube on mount (with tripod); SkyWire GoTo control lying on the ground, iPad lying on the table (both hard to see...)

Comment

Because of the low magnification of the Heritage 100P, its operation on the GoTo mount is the least problematic. Small alignment errors are easy to correct, and the object you are looking for is usually at least at the edge of the field of view in the eyepiece. In addition, the alignment can be corrected with the SkyWire control and the iPad App SkySafari, if the error is not too big. In some cases, when the error was too large to be corrected directly, I managed to move the position in several steps to a correct one, but this was a little tedious at times.

If you operate the 100P on the GoTo mount, you will not see more sky objects than without, but you will find more, and sometimes you can recognize that something is actually the object you are looking for, although you would not have thought so when controlling the telescope manually.

It also makes a big difference regarding the "search speed", whether you work with or without a GoTo control. With the GoTo control, you can always browse through your object list by entering the object names into the handbox or by tapping the objects in SkySafari again and again and without any problems and thus, run through a dozen of objects over and over again. Manual operation takes, of course, much longer, especially with difficult to find objects. You have to decide on your own what ultimately is more fun. For me, this changes from time to time... In any case, when using the GoTo control it is quite reassuring to know that you have found the object you are looking for and not one directly next to it, and that it looks this way and not differently...

Mount with Skymax-102 OTA

Skymax-102 tube on mount (overall view)

Skymax-102 tube on mount, turned around (overall view)

Ditto (detail)

The position of the red dot finder is not very useful - I have to find a better solution for this

Comment

The Skymax 102 OTA (tube) is the most problematic one to use on the GoTo mount due its high magnification (planetary telescope!). Small alignment errors, which are hardly disturbing at the 100P, mean that sky objects cannot be found, especially if you switch between opposite directions. Also correcting the position via the SkySafari app is more difficult, because the deviation between the target, which one wants to access, and the one, which one actually points to, must not be too big.

Here I still need a lot of experience, so that this matter does not end up in frustration only...

Mount with Heritage P130 Telescope Tube

The Heritage P130 tube weighs less than 4 kg and can therefore also be used on the Star Discovery mount. This is more or less the maximum that this mount can carry (think of the weight of the eyepieces!). Most 6" tubes (150 mm, about 6 kg) seem to be too heavy for this mount.

P130 "compact" seen from the side

P130 in "working mode", overview

Ditto, seen from the other side

Comment

I have used the Heritage P130 tube on the GoTo mount the least so far, and I also did not record my experiences with it systematically. I, however, faintly remember that I experienced some frustration due to alignment problems with this tube as well. When I used the Heritage P130 on the GoTo mount in February 2017, all worked fairly well althought the aligment was not perfect. I just used the handbox since I knew the object names by heart and slightly corrected the positions in the eyepiece after an object had been accessed. Thanks to the small alignment error, this presented no problem to me.

By the way, since the P130 tube is quite top-heavy, I utilized the long prism rail and suspended the tube relatively deeply. In this case, an "overhead movement" is, of course, impossible. At the moment, I do not know whether the control would try to get to the taget as quickly as possible using such movements...

Nevertheless, further attempts are needed before I will be able to judge this appropriately.

 

Preliminary Conclusions

First attempts at using the GoTo mount with my different telescope tubes were encouraging on the one hand, but on the other hand, they were sometimes very frustrating. Sometimes, I quickly managed to align the mount well (using two stars), but sometimes not at all. In part, these differences can be attributed to the difference in magnification that can be achieved with the tubes - the Heritage 100P is the most benign in this respect because of its low focal length (and thus, magnification). In part, it may also have been a matter of how far apart the observed objects were in the sky. Let's see whether I can become better in this matter...

Nevertheless, I have already been able to find and observe some deep-sky objects with the GoTo mount, which were, of course, primarily "classics" (M13, M92, M31, ...) that are easy to observe. I will describe my "deep-sky experiences of a beginner" on separate pages, perhaps they may be useful for other beginners. Here are already the observations made in February 2017: Deep Sky Winter Observations February 2017

All in all, the mount has opened the way to the world of deep-sky objects for me, also because I finally acquired the appropriate literature. Without this and a certain preparation for the observation objects, it just does not seem to work, as my experience shows. Thus, in 2016 I was able to observe more such objects than in my whole life before. In addition, these experiences helped me to find larger deep-sky objects without technology, but with literature, using the compact and thus, easily transportable Heritage 100P on my vacations!

I would not want to return the GoTo control any more. Nevertheless, I operate, particularly the 100P, but also the other two telescopes, manually much more often, especially when I want to watch something quickly and without a lot of preparation. I do not know, whether a point-to-solution would be good enough for me as well. I would probably miss automatic tracking. This one is not overly accurate, but it is sufficient to quickly show someone else sky objects at higher magnifications. In this case, the sky objects move very fast out of the field of view if there is no automatic tracking.

 

Links

 

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20.03.2017