Dobsonian telescopes are highly recommended as a starter telescope, a beginner telescope, a telescope for a kid, or even to get the best telescope for the money.
They offer large apertures, a simple mount, and good seeing quality to observe the skies.
The Orion SkyQuest XT4.5 is one such scope that has a larger aperture than similarly-priced refractors, offers simple alt-azimuth motion on a wooden base, and provides good seeing quality to see both local bodies and far-off DSOs.
How good will it be for your space-obsessed child or for your growing interest in astronomy?
Read on to find out.
Zooming in…
✔️ Best Feature: Seeing quality
❌ Worst Feature: Spherical mirror
👌 Ideal For: Celestial Viewing, Stargazing, Lunar & Planetary Observation, Bright DSO Viewing, Kids, Beginners, Intermediates, Experts
- Optical Design: Reflector
- Aperture: 114 mm (4.5”)
- Focal Length: 900 mm
- Focal Ratio: f/7.9
- Eyepieces Included: 25 mm, 10 mm
Our Verdict: The SkyQuest XT4.5 Dobsonian is an all-purpose telescope that gives you a taste of both planetary and DSO observations. Even though you may be considering it for a child, it’s not a kid’s toy and will actually provide great performance for the entire family to enjoy.
Who is the Orion SkyQuest XT4.5 Classic Dobsonian Best Suited to?
The SkyQuest XT4.5 is a telescope designed for kids and adults that are new to astronomy and using telescopes. Yes, you can likely find a cheaper 4” Dobsonian in the market, but the SkyQuest has some convenient features that makes it an ideal setup for a beginner. The carry handle, spring tension system, and navigation knob are the perks that add some value to the XT4.5 model.
Even though it’s an entry-level telescope at an affordable price, more experienced users may like its portable and lightweight setup. The fact that you don’t have to disassemble the tube from the mount is a bonus, and the tube is long enough to provide some height without having to place it atop a platform like a table unless you want to.
How Does the Orion SkyQuest XT4.5 Classic Dobsonian Perform?
The XT4.5 performs right within its expected range. Of course, it provides stellar lunar observation and some imaging with a smartphone, but it also provides somewhat of an edge for planets with its medium speed focal ratio and longer focal length compared to faster Dobs. So yes, you can see planets and some features, and you can even reach out further to galaxies, nebulae, and star clusters.
Its mount provides alt-azimuth motion and the tube is easily moved with the integrated navigation knob. The base has feet that are spaced further apart, but it ultimately adds to stability. Both mirrors are collimatable, supplied accessories work well with the setup arrangement, and the SkyQuest telescope won’t break the bank.
Features & Benefits
Seeing Ability
The SkyQuest has very good optics that seem sharper the eye than many of its competitors in the market. With its focal specs, the field of view will be narrower than a faster Dobsonian, so you may struggle to fit in large DSOs like some large star clusters and nebulae. However, it does allow for that little bit of extra seeing ability on planets.
You can use longer eyepieces for their forgiving eye relief and expect much higher magnification. And yes, you can see distant DSOs with the 4.5” primary mirror even though it is the smallest scope in its series.
Locally, the SkyQuest provides excellent lunar resolution. It’s good enough for imaging, if your type of imaging is with a smartphone, and that will be the extent of its astrophotography benefits. You can try for photos of planets, but the resolution will only be good enough to share with friends. By no means will it match Hubble telescope quality.
Ergonomic & Handling Features
Conveniently, Orion outfitted the SkyQuest with a navigation knob. This knob allows both up/down and sideways movement of the tube. Essentially, it provides a convenient handling point for moving the tube to either track a target or quickly point the scope in the direction of a desired object.
There is also a carry handle built onto the optical tube that makes the entire set up ridiculously easy to transport. To help with easy transport, the telescope also features Orion’s CorrecTension Friction Optimization System that incorporates secure fastening via springs. With this setup, you won’t have to remove the tube from the mount for transportation which in turn reduces setup and pack-up time and difficulty.
Apart from its convenient handling features, its weight and size fall within reasonable and portable standards. The tube is 35” long, but that is due to the longer 900 mm focal length. But, since we know that Dobsonian bases are often the hefty part of the entire setup, this telescope system weighs only 17.6 lbs total.
Supplied Accessories
Fortunately, you’re not seeing any budget or plastic eyepieces included with the SkyQuest telescope. What you get are two Plossl eyepieces: 25 mm and a 10 mm. I suspect that the focal length is actually 910 mm and not 900 mm as listed on the Orion website as the math for the eyepieces match that of a 910 mm focal length.
With this calculation, the 25 mm provides 36x magnification and the 10 mm provides 91x magnification that lines up with Orion’s magnification statements. As Plossl eyepieces, they have quality glass and good optical coatings. They can be paired with a Barlow lens to take advantage of its highest useful magnification.
A collimation cap is included to collimate the mirrors inside the tube. An essential feature to point out is the collimatable primary mirror. This will prove to be vital when the optics become misaligned.
A 6×26 correct-image finder is also included. While new users may be excited by the fact that it allows for correct-image seeing, the prism within the finderscope will dim the view as light is lost through the optical path. Additionally, it already has a small 26 mm aperture to begin with and that will make it difficult to see much. It may be the first accessory you should consider replacing.
A 1.25” rack-and-pinon focuser comes with the tube, and it does its job nicely and is compatible with 1.25” accessories. It won’t provide the fine-focusing necessary for astrophotography, but this scope isn’t recommended or suited for imaging anyway.
Limitations
Spherical Mirror
Spherical mirrors in a Newtonian produces spherical aberration that is manifested to the eye as blurry seeing quality due to the multiple focal points of light rays as they bounce off the mirrored surfaces. So, seeing a spherical mirror in a telescope does raise some red flags.
However, there is a saving grace here that helps to reduce its effect and provides more than decent seeing quality – the focal ratio. Due to the longer focal length and slower focal ratio of approximately f/8 compared to faster Newtonians, the effect of aberrations are reduced. But, what aberrations are present may be exaggerated at higher power. A Barlow lens may be able to help mitigate the effects, but it may also introduce its own set of aberrations if it’s low quality.
Popular Questions
Can you Take Photos with the SkyQuest 4.5 Telescope?
While you may be able to take amateur photos with a smartphone and an adapter, you won’t be able to use DSLR cameras or reach focus or take long exposures. There is also the issue of using a 1.25” focuser for heavy loads required for astrophotography, and of course, the need for an EQ mount and likely motorized control for tracking objects.
All in all, a Dobsonian isn’t the type of telescope you need if you want to pursue astrophotography capabilities.
Can the Orion Dobsonian be Mounted on a Tripod?
The Dobsonian mount and base cannot be mounted to a tripod. The base is designed to be placed on the ground or atop a very solid surface like a table. The optical can be mounted to a tripod or different mount, but it will require additional parts and adapters to obtain this setup. If that is the setup you want, it’s best you look at something other than a Dobsonian.
Is the Orion SkyQuest Good for Terrestrial Viewing?
The Newtonian optics do not make it suitable for terrestrial viewing. Images will appear to be upside down and backwards. It’s not recommended to use a Dobsonian for terrestrial viewing. However, the 6×26 finderscope has a correct-image prism that allows for viewing terrestrially, but since the aperture is so small, even a larger pair of binoculars would be more suitable for terrestrial purposes.
Can you Lock the Tube in Place on the Orion SkyQuest XT4.5?
There are no locking knobs or mechanisms on the SkyQuest telescope. The XT4.5 has the CorrecTension Friction Optimization System that allows some play with the tube so that it can move freely when the navigation knob is used. However, the tube remains well-balanced with the spring tension system even when switching out eyepieces.
Conclusion
What makes the SkyQuest one of the best reflector telescopes for the price is the fact that the tube is longer, so it doesn’t need to be placed on a table.
The optical specs balance out the spherical mirror, and it provides medium-speed viewing quality that makes it an all-purpose telescope for the skies.
The convenience upgrades also add to its user-friendliness. The SkyQuest is a solid reflector that you can afford on a tight budget. It’s suitable for every type of user as it provides good seeing quality for many types of targets.
It’s not just a scope for the kids.
In fact, you may find yourself using it more often than anybody else.
