The Sky-Watcher Virtuoso GTi 130P and GTi 150P telescopes represent a significant leap in amateur astronomical equipment, melding the esteemed design of the Heritage 130P and 150P tabletop Dobsonians with advanced technological features without sacrificing the simplicity that makes them so great.
At the heart of the Virtuoso GTi series are the 130mm and 150mm telescope optical tubes, each identical to the Heritage 130P and 150P telescopes, respectively. These telescopes provide excellent wide-field views of star clusters and nebulae but offer enough light-gathering power to view smaller deep-sky objects like planetary nebulae, globular star clusters, and even galaxies in some detail under a dark sky. Their optics are no slouch on Solar System objects either; these “light buckets” perform just as well as a “premium” telescope of the same aperture and offer razor-sharp views of the Moon, planets, and double stars when properly collimated on a clear and steady night. And of course, the collapsible tubes and tabletop mounts of these telescopes make them extremely portable, allowing them to sit in a closet or on a bookshelf when not in use and fitting within airline carry-on requirements when disassembled.
The main enhancement of the Virtuoso GTi series over their Heritage 130P/150P counterparts is the addition of GoTo technology, a system of hardware and software that enables these telescopes to automatically locate and track celestial objects, a significant advantage for those learning their way around the night sky or for observing sessions where time is limited. The Virtuoso GTi is controlled via an app on your smartphone rather than with an old-fashioned hand controller and runs on quiet, high-quality motors that consume relatively little power and can precisely track celestial objects for hours.
An equally critical feature of the Virtuoso GTi telescopes is Sky-Watcher’s “FreedomFind” dual encoders. Unlike most other GoTo telescopes, where you are inexorably married to the electronics and manual adjustments are either impossible or bound to cause issues with the telescope’s GoTo functionality, the Virtuoso GTi telescopes can be aimed manually when powered off if you’re in a hurry, and thanks to the FreedomFind encoders, making manual adjustments when the mount is powered on will have no effect on the telescope’s ability to precisely maneuver to and track celestial objects.
Additionally, unlike many other tabletop Dobsonians, the Virtuoso GTi telescopes are designed to be able to be mounted on a tripod, thanks to their inclusion of a threaded socket on the bottom of their base, which is compatible with the 3/8″-16 stud on most heavy-duty tripods.
In terms of cost-effectiveness, the Virtuoso GTi telescopes, particularly the 150P, offer exceptional value for the money with their combination of affordability, advanced features, and quality optics. Few other telescopes are a more compelling choice than the Sky-Watcher Virtuoso GTi 130P and 150P for anyone looking to explore the wonders of the night sky.
|Virtuoso GTi 130P
|Virtuoso GTi 150P
The Sky-Watcher Virtuoso GTi 150P and 130P are both some of our top-rated telescopes, as are the manual Heritage 150P and 130P models. However, it’s hard to come up with a reason to choose the Virtuoso GTi 130P unless the Heritage/Virtuoso GTi 150P models are both out of stock. For one thing, the price difference between the two is negligible, along with everything else besides the improved performance of the larger aperture model.
It’s also important to consider that the Virtuoso GTi 130P has an identical computerized base to the GTi 150P, which means that it is quite a bit wider, heavier, and overall less portable than its manual counterpart, the Heritage 130P, and also no more convenient to lug around than either the Heritage or Virtuoso GTi 150P. All in all, we would highly recommend the Virtuoso GTi 150P model if it is available to you over the 130P whenever possible, though both are excellent telescopes.
Optical Tube & Performance
The most significant difference between the Virtuoso GTi 150P and 130P lies in their aperture sizes. The Virtuoso GTi 150P, with its larger 150mm (6”) aperture, offers about 15% more resolving power than the 5.1” 130P. Both the Virtuoso GTi 130P and GTi 150P are Newtonian reflectors with an f/5 focal ratio. Both of these telescopes have parabolic primary mirrors that are tested and precisely polished to provide sharp images. The GTi 130’s primary mirror, at 130mm (5.1 inches), has a 650mm focal length, whereas the GTi 150’s mirror, a bit larger, has a 750mm focal length. Consequently, with the same eyepiece, the Virtuoso GTi 150P achieves 15% more magnification than the Virtuoso GTi 130P.
The extra inch of aperture possessed by the Virtuoso GTi 150P, though seemingly a modest increase on paper over the 130P numerically, has a substantial impact on the viewing experience. When observing planets, for instance, the GTi 150P’s 33% greater light-gathering ability over the 130P translates to brighter and more vivid images at the same magnification, as well as offering 15% more resolving power. The greater light-gathering and resolving power of the 150P will allow you to see Neptune’s moon Triton where the 130P might struggle, and it will make it easier to identify subtle blue festoons in the atmosphere of Jupiter, for instance.
Deep-sky views are where the GTi 150P’s additional aperture really shines, however. The 33% greater light-gathering prowess of the GTi 150P reveals fainter stars, allowing you to more easily resolve globular clusters and bringing out more detail in wispy nebulae. Bright stars appear more vivid and colorful, while the threshold at which stars begin to appear colorless is a bit dimmer with the 150P over the 130P owing to its larger aperture. And while neither the 130P nor the 150P are ideal for observing galaxies due to their relatively small apertures, the GTi 150P does have an edge when you’re trying to discern hints of detail, and its larger aperture over the 130P makes it easier to spot fainter galaxies on the edge of visibility, especially under light-polluted skies.
A standout feature of the Virtuoso GTi telescopes, like their Heritage 130P/150P counterparts, is their collapsible optical tubes. The upper half of the tube is replaced by a pair of collapsible struts attached to a plastic ring, which has a molded-on 1.25” helical focuser, a mount for the telescope’s provided red dot finder, and, of course, supports for the secondary mirror. When not in use, the struts can be collapsed, reducing either optical tube to about half their extended length.
In terms of optical performance, both the Virtuoso GTi 130P and GTi 150P excel. Despite the challenges of crafting a high-quality primary mirror with a relatively fast focal ratio of f/5, the smaller size of these telescopes minimizes the difficulty and cost of doing so. These telescopes’ optics are just as good as any other model or optical design of similar aperture, and the open-tubed design of these telescopes further reduces concerns about cooldown or tube currents impacting performance. However, precise collimation is essential for sharp views with any Newtonian reflecting telescope, and you will have to collimate the primary mirror of the Virtuoso GTi 130P and 150P fairly often, if not necessarily every time you set up one of these telescopes. The primary mirror of both the 130P and 150P requires no tools to adjust; the secondary mirror’s collimation can be adjusted with a small hex wrench.
The primary mirrors of the Virtuoso GTi 130P and GTi 150P are made from regular soda-lime plate glass, which does expand and contract more from temperature changes than low-expansion Pyrex or quartz. However, these telescopes are relatively small, and the primary mirrors themselves are quite thin; cooldown time is negligible in most cases, and you won’t need to bother with adding a fan to the back of these scopes. The open tube helps with reducing the effects of the boundary layer or any tube currents above the primary mirror.
The focuser on both the 130P and 150P is a simple helical unit, which you twist in and out to adjust focus. It only accepts 1.25” eyepieces, but the field of view you get with just the stock 25mm 3-element eyepiece provided with either of these telescopes is over 2 degrees, or 4 times the angular diameter of the full Moon (2.2 degrees and 2.5 degrees maximum with the 150P and 130P, respectively). A heavy, wide-angle 1.25” eyepiece can strain the focuser and cause issues with the focuser or the entire upper tube assembly of the 130P/150P flexing or sagging. But most modern UWA-type eyepieces aren’t heavy enough to cause this. That being said, if you are using a monster 13mm XWA or Ethos with one of these telescopes, you are going to have a bad time. Otherwise, don’t worry about it. The coarse threads in the plastic can make it hard to focus these telescopes precisely at high magnifications; adding a layer or two of Teflon pipe tape to the threads can help to reduce any inherent play/wobble and improve the overall smoothness of the focuser.
The Virtuoso GTi 130P and 150P models are each equipped with two “Super” 1.25” eyepieces, a 25mm offering 26x/30x magnification for the GTi 130P and GTi 150P, respectively, and a 10mm eyepiece providing 65x/75x magnification. These eyepieces feature a 3-element design based on the Konig configuration and yield an approximate 55-degree field of view. While their construction is primarily plastic, they offer satisfactory performance for a kit eyepiece at this price point. The 25mm eyepiece provides near the maximum field of view you can get with a 1.25” eyepiece and is fairly sharp out to the periphery, if not perfect; the 10mm has more eye relief than a typical Plossl or Kellner but does have issues with glare and some slight chromatic aberration on bright objects like the planets.
On the whole, the eyepieces included with the Virtuoso GTi scopes are satisfactory; you might want to consider replacing the 10mm with an aftermarket 9mm redline/goldline eyepiece, however. It’s also certainly advisable that you obtain a shorter focal length eyepiece for higher magnification, like a 4mm planetary eyepiece or a 6mm redline/goldline, in addition to any additional focal lengths in between for different magnification options. The 65x/75x provided by the 10mm Super eyepiece is far from enough magnification for optimal planetary views with these telescopes on a good night; their best performance on planets or double stars tends to be at magnifications in the 150-200x range. But for viewing deep-sky objects, you’ll want to stick with lower magnifications most of the time.
Both the GTi 130 and GTi 150 include a basic collimation cap, essentially a plastic cap for the focuser with a hole poked in it and some reflective material added on. This tool is enough to precisely collimate the Virtuoso GTi telescopes on its own; for further precision, you can always point the telescope at a bright star. Our collimation guide goes over both of these methods in detail. A laser collimator would be ill-advised for these telescopes due to the rather flexible nature of the 1.25” helical focuser; most good-quality lasers are quite heavy and will cause the plastic focuser to sag, ruining any ability to accurately use them for alignment.
Accompanying each Virtuoso GTi telescope is a red dot finder, which is more than enough for aiming these telescopes by hand and for lining the Virtuoso GTi mount up on a set of known stars to enable precise automatic pointing and tracking.
The Virtuoso GTi telescopes use a tabletop alt-azimuth fork mount; technically, due to the one-armed design and use of ball bearings, it has no resemblance to a true Dobsonian mount mechanically besides being made out of particle board; however, the design of the Virtuoso GTi is close enough in outward appearance and handling that it is perfectly fine to call these telescopes Dobsonians anyway. The Virtuoso GTi mount is exactly the same for both the 130P and 150P models.
Clutch knobs on the altitude (up/down) and azimuth (left/right) axes of the Virtuoso GTi mount allow you to unlock the mount and aim the telescope manually like you would with a conventional Dobsonian telescope. Unpowered, the Virtuoso GTi mount handles the same as any manual alt-azimuth mounted telescope, moving smoothly on ball bearings with a pair of clutches to adjust friction. But compared to the manual-only Heritage 150P/130P or a normal Dobsonian, it is quite a bit more difficult to smoothly track objects with the Virtuoso GTi telescopes by hand at high magnifications or make any sort of fine adjustments manually at all, ironically owing to the silky smoothness of the ball bearings. However, it should come as no surprise to you that the Virtuoso GTi mount is designed to be used mainly when powered on, and the electronics are certainly worth utilizing if you plan on observing for an extended period. A battery compartment in the side of the GTi mount allows you to run it for several nights off AA batteries, or you can connect an external 12-volt power source. The Virtuoso GTi uses a lot less power than most GoTo mounts, and you can always make larger movements around the sky by hand to save power, thanks to the FreedomFind dual encoders in the mount.
Control of the Virtuoso GTi mount is accomplished with the SynScan app, unless you go and buy a SynScan controller to operate the mount with or opt to plug it directly into a PC with the appropriate cables. The SynScan app works well enough; you can get it to pair with SkySafari Pro for a more user-friendly experience with a wider database, but not all devices will allow you to do so; specifically, most Apple products can’t support this option. My iPhone will not allow me to run both the SynScan app and SkySafari at the same time, so I have only been able to use the SynScan app with it, for instance. However, if you are running a device with Android, this is not a problem. If you find yourself using your Virtuoso GTi a lot, it wouldn’t be a bad investment to get a small Android tablet just for running SkySafari/controlling the Virtuoso regardless of your smartphone’s compatibility, since controlling the mount also requires you to disconnect your phone/tablet from any other Wi-Fi networks and connect to the GTi’s internal network.
If you are using the Virtuoso GTi with the electronics powered on, the alignment process for the onboard GoTo system is dead simple. The SynScan app offers numerous alignment options, including level-north, 2- and 3-star alignments, or using the Moon or a planet. A multi-star alignment is the most accurate, of course, but the least convenient. You can, of course, simply grab the telescope and aim it manually at any time, including during the alignment process, to no ill effect, thanks to the “FreedomFind” dual encoders in the telescope, which keep track of any adjustments you make by hand and input them into the telescope’s control software. You can also improve the Virtuoso GTi’s pointing/tracking accuracy by syncing the telescope/mount on a known object in the SynScan app whenever it is convenient or necessary to do so.
Sky-Watcher has also elected to bolt a block of plastic with a ⅜”-16 threaded socket to the bottom of the Virtuoso GTi mount – which would be really nice to have on the manual Heritage Dobsonians too, I suppose. This stud allows you to attach the Virtuoso GTi to a sturdy photo tripod as well as some of the tripods supplied for astronomical telescope mounts, which can be a huge boon for portability. However, you will need to confirm that you have a tripod that has a ⅜”-16 stud when the head is removed, which may not be the case, and possess a fairly substantial tripod as well; a surveyor’s tripod is the most affordable option that fits the bill in many cases. You might be better served by making your own simple tripod or stand, either one that the Virtuoso GTi simply rests atop or with a threaded screw connection. Plenty of guides online detail how to do so.
Given their motorized pointing and tracking abilities, the Virtuoso GTi telescopes can be used for astrophotography. The inability to use a coma corrector and the mechanical play in the 1.25” helical focuser of the 130P/150P optical tubes will limit your choice of camera, however.
For deep-sky imaging, the Virtuoso GTi mount lacks the precision to take long exposures, and its alt-azimuth nature will inherently lead to trailing in frames over 15-20 seconds. However, with short exposures and the latest high-sensitivity cameras from companies like ZWO, QHY, and Player One, it is possible to take some surprisingly good photos of smaller targets like globular clusters and nebulae with dozens or hundreds of frames and relatively short exposure times of just 5–10 seconds. Reaching prime focus with almost any camera will require you to retract the trusses of the 130P/150P tube slightly to bring the sensor close enough to the primary mirror.
The Virtuoso GTi 130P and 150P are also both ideal for “electronically assisted astronomy” or “live stacking,” where a series of short exposures are stacked together in real time for viewing. Popping a camera like the ZWO ASI224MC into the Virtuoso GTi 130P or 150P gives you roughly equivalent equipment specs and capabilities to the Unistellar EVscope, which costs far more and offers far less flexibility than the GTi and a third-party camera. A high-end camera with a cooled sensor coupled to the GTi 130 or 150P will allow you to take images that easily outperform any “smart telescope” on the market today.
For planetary imaging, the Virtuoso GTi telescopes are both on the small side for achieving sufficient resolution and brightness, but they will do the job. You will want a 5x—that’s right, 5x—Barlow lens to boost these telescopes to an f/25 focal ratio and a 3250mm/3750mm focal length for the 130P and 150P, respectively, along with a suitable planetary camera, a laptop with plenty of RAM, and some sort of external SSD with at least a terabyte of storage.
Any sort of astrophotography with the Virtuoso GTi is best conducted with the bottom of the mount attached to a steady, heavy-duty tripod to prevent any issues with the telescope wobbling or displacing itself during an imaging session.