The Optical Tube
The StarSeeker IV 130mm’s optical tube is comparable to most 130mm f/5 Newtonians on the market. These usually have decent optics, and the 5.1″ aperture is sufficient for serious deep-sky observation, as well as lunar and planetary viewing. An f/5 Newtonian exhibits a minor coma at low magnification at the field of view’s edges with a wide-angle 2″ ocular (or if you scrutinize the edge of the field with a 1.25″ eyepiece). However, given the StarSeeker IV 130mm’s 1.25″-only focuser, you’ll likely never notice it. Be mindful that many inexpensive wide-angle eyepieces might display similar aberrations at the field’s edge in an f/5 Newtonian when shopping for additional eyepieces.
Collimating the StarSeeker IV 130mm could be challenging for a first-time user, particularly since the telescope doesn’t include a collimation tool. We recommend reviewing our collimation guide to learn more about this procedure. The 130mm model does have adjustable collimation for both mirrors, unlike the larger StarSeeker IV 150mm, which has a fixed primary mirror.
Like many telescopes, the StarSeeker IV 130mm connects the tube and mount using a Vixen-style dovetail rail and clamp. Technically, you could mount the StarSeeker IV 130mm on a different mount, but this might lead to an uncomfortable eyepiece position, and astrophotography with a DSLR or similar would place excessive strain on the 130mm’s plastic focuser.
The focuser on the StarSeeker IV 130mm Reflector is a 1.25″ unit, composed almost entirely of plastic. It functions adequately, but it may present some wobble if you attach a heavy camera or eyepiece. Replacing it with a high-quality Crayford focuser requires a degree of comfort in modifying the telescope and removing the optics, but can be done with relative ease.
Accessories
The StarSeeker IV scopes include 23mm and 10mm aspheric eyepieces with a 62-degree apparent field of view, offering 33x and 75x magnification, respectively. These eyepieces utilize two glass lens elements and an aspheric plastic lens element. Surprisingly, they perform quite well (particularly the 23mm) and are a step above the inexpensive Kellners or plastic Plossls supplied with many entry-level scopes. However, almost any telescope would undoubtedly benefit from authentic Plossl or wide-angle eyepieces instead of these cheap oculars, whose mediocre performance is somewhat disappointing for a $600+ telescope. The plastic lens element in either eyepiece is also easily scratched, and being the eye lens, it is almost impossible to avoid scuffing it over time.
The StarSeeker IV 130mm Reflector also comes with a standard red-dot finder for aligning the mount’s GoTo system.
The StarSeeker IV Mount
The Orion StarSeeker IV mount is a fairly standard GoTo alt-azimuth mount, pointing up-down and left to right. It is attached to a sturdy steel tripod, and attaches to optical tubes, including the provided 130mm f/5 with a standard Vixen-style dovetail saddle. While you can run it off AA batteries, we’d recommend purchasing a rechargeable power supply for cost-efficient long-term use. The StarSeeker IV is a GoTo mount that automatically points to and tracks targets. With just a single button press, the StarSeeker IV effortlessly glides across the sky, providing access to a vast array of tens of thousands of celestial targets while seamlessly tracking the sky no matter the object being observed. The mount also features dual encoders, allowing you to grab it and push it around the sky manually at your leisure without affecting its GoTo or tracking accuracy.
The StarSeeker IV mount also features a built-in WiFi module. This enables you to control the telescope and view its orientation using SkySafari or the free SynScan Pro app, providing a much more user-friendly interface than the sometimes-included hand controller.
Should I buy a Used Orion StarSeeker IV 130mm Reflector?
It is important to proceed with caution when considering purchasing any used telescope, especially a GoTo scope like the StarSeeker IV 130mm. The biggest potential issues to be aware of include any faults with the electronics or possible degradation of the mirror coatings. These factors could significantly deter you from purchasing a second-hand unit.
Minor dents in the StarSeeker IV 130mm’s tube that do not impede the light path of the optics aren’t a major concern, and larger dents can typically be remedied with the use of an automotive dent puller. As is standard practice, it’s prudent to ensure that components such as the plastic focuser and the tripod are free from damage, and the mirror coatings should be clear and devoid of corrosion. The cost to recoat the mirrors in the event of significant damage or reflectivity loss is likely to exceed the price of a new set of optics for a telescope of relatively modest aperture such as the StarSeeker IV 130mm.
Alternative Recommendations
In addition to Dobsonians, there are a few other, better 130mm reflectors available with the same optics and similar features as the StarSeeker IV 130mm, which we’d probably recommend instead, namely those from Celestron and Sky-Watcher.
Under $600
- The Sky-Watcher Virtuoso GTi 150P has a larger aperture than the StarSeeker IV 130mm and is equipped with a fully motorized mount featuring GoTo capabilities. This can be controlled via your smartphone or tablet and includes FreedomFind encoders, just like the StarSeeker IV 130mm. However, the additional inch of aperture delivers considerably brighter views with enhanced sharpness and resolving power. The collapsible tube and tabletop Dobsonian mount make setup quick and transport almost anywhere a breeze. The manual Heritage 150P shares identical features, performance, and accessories with the GTi 150P, with the only difference being the absence of electronics, resulting in an entirely manual tabletop Dobsonian telescope.
- The Sky-Watcher Virtuoso GTi 130P contains the same optics as the StarSeeker IV 130mm but comes in the same collapsible tube as the 150P, mounted on a GoTo tabletop Dobsonian mount. The more affordable Heritage 130P is identical, except for the absence of GoTo and motorized tracking capabilities.
- The Celestron Astro Fi 130 features the same optics and basic design as the StarSeeker IV 130mm, but with better eyepieces, a better focuser, and a lower sticker price, though it lacks the StarSeeker IV’s manual aiming option or FreedomFind system.
$600-$800
- The Apertura AD8/Zhumell Z8/Orion SkyLine 8 possesses 2.5 times the light-gathering capability of the StarSeeker IV 130mm and 60% greater resolving power. This enhancement turns “faint fuzzy” deep-sky objects into recognizable and intricate wonders, unveils the disks of faint ice giant planets, and displays details on Mars and Jupiter that are unattainable with a mere 5.1″ of aperture. Moreover, the dual-speed focuser, inclusive eyepieces, and additional features like the built-in cooling fan and adjustable bearings for balance offer exceptional value for the price.
- The Celestron StarSense Explorer 8″ Dobsonian is rather basic in terms of its features and accessories, including only a single eyepiece, a single-speed 2″ Crayford focuser, and a red dot finder. Nonetheless, it incorporates some computerized functionality through Celestron’s StarSense Explorer technology. While it doesn’t automatically move the telescope or track celestial objects with motors, it does use your smartphone as a pointing aid to help locate objects in the night sky. Furthermore, the compact and lightweight Dobsonian base, along with carry handles on the tube, make transportation a breeze.
$800-$1200
- The Apertura AD10/Zhumell Z10/Orion SkyLine 10 shares the same outstanding accessories, features, and value for money as its smaller counterpart. The 10″ optical tube and base weigh only slightly more than the AD8/Z8 and are not much more challenging to store or transport, despite offering a significant increase in light-collecting and resolving power.
- The Celestron StarSense Explorer 10″ Dobsonian offers the same exceptional StarSense Explorer technology as the 8″ model, but with an increased aperture and more straightforward collimation. Its lightweight and ergonomic design makes it significantly easier to set up and transport compared to many other 10″ Dobsonians.
- The Celestron NexStar 6SE features slightly more aperture than the StarSeeker IV 130mm enabling better performance, though with more than twice the focal length, it suffers from a narrow field of view. The mount also lacks any manual aiming options, unlike those from Sky-Watcher and Orion.
Aftermarket Accessory Recommendations
The StarSeeker IV 130mm can accommodate up to 200-250x magnification with its 5.1″ aperture and sharp optics, but you’ll gain the most benefit from 150-200x magnification. Increasing magnification further will have diminishing returns. The often-mentioned 6mm “redline” or “goldline” eyepiece offers 108x magnification with the StarSeeker IV 130mm, while a 4mm planetary eyepiece provides 163x magnification. Higher magnification is ideal for observing planets, globular star clusters, planetary nebulae, and resolving close double or triple stars. We would also recommend replacing the provided aspheric eyepieces with a 20mm redline/goldline (33x) or 25mm Agena Starguider (26x) for low power and a 9mm redline (72x) at the high power end. A 15mm GSO SuperView or redline (43x) might also be a good addition for medium magnification. And for those with an interest in employing the highest possible magnification, a 3.2mm planetary eyepiece would deliver 203x magnification with the StarSeeker IV 130mm and is ideal for splitting close double stars when conditions permit.
To facilitate sharp views, a collimation tool will be a necessary addition. Given the potential for a laser to cause sagging in the StarSeeker IV 130mm’s plastic focuser, we would recommend a straightforward collimation cap or Cheshire tool.
A narrowband, ultra-high-contrast (UHC) nebula filter might be somewhat expensive, but it significantly enhances the visibility of nebulae through the StarSeeker IV 130mm or any other telescope, regardless of the sky’s light conditions. We recommend the Orion Ultrablock 1.25″ UHC filter; it will improve the views of emission nebulae like Orion (M42) and the Swan (M17), and also help reveal planetary nebulae and previously-invisible targets like the Veil Nebula or North America Nebula under dark skies. While a UHC filter doesn’t eliminate light pollution, nor can any other filter or device, it helps mitigate light pollution’s effects on most nebulae and enhances contrast under any conditions.
Lastly, you’ll want a power supply such as those from Talentcell, Westinghouse, or a Celestron PowerTank Lithium to run the StarSeeker IV mount for long periods without running through piles of disposable batteries.
What can you see?
What you can see when it comes to deep-sky objects with the StarSeeker IV 130mm, or any telescope for that matter, is largely influenced by the level of light pollution in the skies where you observe. Under urban skies, you’re limited to open star clusters, like M11 or M45, and the brightest nebulae, such as Orion (M42), which will appear washed out compared to their splendor under better conditions. Darker skies will enable you to resolve globular star clusters like M3 and M13 into individual stars with the StarSeeker IV 130mm at high magnification, and you can also spot dust lanes in the brightest galaxies like M31 or M82. The StarSeeker IV 130mm also excels for viewing large nebulae, particularly with a UHC nebula filter, such as M8 (the Lagoon) or the vast Veil Nebula complex in Cygnus.
The 130mm (5.1″) aperture of the StarSeeker IV 130mm combined with its sharp parabolic primary mirror means that this scope, of course, does a commendable job on the Moon and planets. You’ll be able to discern thousands of craters, mountains, and ridges on the lunar surface, which are merely miles in size; the phases of Mercury and Venus; and the polar ice caps on Mars. When Mars is closer to Earth, you might also distinguish a few dark markings and any ongoing dust storms. The StarSeeker IV 130mm will not only show you Jupiter’s moons, but it’s also large enough to resolve them as minuscule disks, along with their shadows, when they transit in front of the planet. Jupiter itself displays colorful, ever-changing cloud belts, festoons, and storms in a variety of hues, from white to pink, blue, and brown. On a favorable night, you can also resolve the Great Red Spot with the StarSeeker IV 130mm. Saturn’s rings and the Cassini division within the rings can be observed.
Astrophotography
Since the StarSeeker IV mount features built-in motorized tracking, astrophotography is possible with all models, including the 130mm. However, due to the physical limitations of the plastic 1.25” focuser, and alt-azimuth mount design, you’re restricted to capturing the Moon and planets. Your smartphone and an adapter can effortlessly capture the Moon through an eyepiece, of course, and by inserting a 3x or 5x amplifying Barlow lens combined with an appropriate > like the ZWO ASI224MC, you can photograph planets, though Mars, Jupiter, and Saturn are likely the only ones of much interest.
