StarNavigator NG 90 Refractor has a major problem; the tripod.
It is hard to understand why Meade sends flimsy, aluminum tripods with comparatively “long” telescopes such as StarNavigator NG 90. If the tripod were a steel model, StarNavigator NG 90 would be one of the easiest to recommend telescopes, but it is not.
If you can handle the tripod problem somehow, by replacing it or improving it, this is a great telescope. The GoTo mount works properly, and the optical tube is well-built. If not, I suggest looking for other options.
900mm Focal Length
The 90mm aperture, combined with the 900mm optical tube, provides an f/10 focal ratio, lowering Chromatic Aberration to almost non-existent levels. (Chromatic Aberration is a colorful halo around bright objects.)
The optical design is sitting at the sweet-spot of length and aperture.
A refractor doesn’t require maintenance, is easy to carry around and gathers %25 more light per aperture compared to Dobsonians. They are extremely advantageous in terms of convenience, and that is why most experienced astronomers keep a refractor for quick observations.
The optical design leans towards planetary performance.
The f/10 optical design is extremely easy to focus at high-magnifications, thus making the telescope a planetary performer. StarNavigator NG 90 Refractor gathers details such as moons of Jupiter, The Great Red Spot, Rings of Saturn, Titan, surface detail on Mars in a breeze.
Phases of Venus are easy to observe, but Neptune and Uranus will appear as blueish dots no matter the eyepiece you are using. On the plus side, they are effortless to find with the GoTo mount, which would have been frustratingly hard with a manual.
Deep Space Performance
StarNavigator NG 90 Refractor is not built for deep space observations. It is hard to fit large objects such as the Andromeda Galaxy inside the view. But it will resolve star clusters and details easily, and chromatic aberration is much less effective on deep space observations.
About half of the Messier Catalog will be within reach on ideal conditions, which is acceptable, but definitely not impressive.
Unstable and Prone to Error
The mount is sturdy, and the locks are strong enough for the motors. It feels much better than manual refractor mounts in terms of sturdiness, and this is a key point. It is incredibly hard to build a sturdy refractor mount, and when they are sturdy, they are expensive. A GoTo mount solves that problem and improves upon it by adding automatization.
If there is a problem to be found with the mount, it is the inability to use it by hand. You have to unlock the optical tube, point to an object, and lock the optical tube again. The telescope won’t balance if it is unlocked. Using StarNavigator 90 NG by hand is not comfortable at all.
The Tripod Problem
The tripod is nowhere near enough for a 90mm refractor on a GoTo mount. These kind of tripods “barely” carry the 50-60$ refractors. It lowers the quality of the package by a huge amount. As long as the tripod is not sturdy, your observations will be frustrating.
A sturdy tripod is the first upgrade StarNavigator 90 NG requires.
GoTo and AudioStar
The mount is more delicate than manual models.
A computerized mount is always more problematic than a manual mount. There is no way around it. If a GoTo mount breaks down, it has to go to the customer service, and you may not see your telescope for months. It is hard to break down a manual mount, and if you do, you can repair it by hand.
But with this sacrifice, you gain the ability to point to any space object in the night-sky on command. And, the delightful auto-tracking feature.
There are a few things you should know about the motors built into the mount. They make a machinery noise when pointing to a new space object, and may ruin a quiet night. They will also break down if you force them to move when locked down.
Other than these problems, they work completely fine. The alignment procedure is incredibly easy, and the computer points to thousands of objects with pleasing accuracy. You can always adjust the view any way you want. I don’t understand how computerized telescopes work this well, but they do.
Some people prefer finding planets, nebulas, and galaxies manually. It is understandable since it gives the same, pleasurable feeling that ancient astronomers had thousands of years ago. But computerized telescopes are the future; there is no doubt about that.
Red Dot Finder
The accessories are all as cheap as possible.
The eyepieces are Kellner models, which are better than the worst model in the market(Huygens). They should be changed as soon as possible.
The focuser is mostly plastic with a 1.25” width. It works well, but with especially heavy eyepieces, it starts to struggle.
The red dot finder is the only adequate accessory in the package. A GoTo telescope doesn’t require an expensive finderscope. You probably will use it at the beginning only.
The amici diagonal is such a cheap choice it breaks my heart. It lowers the image quality and should be changed as well. A star diagonal is not that expensive, and Meade should have sent one.
Apart from the finder, all the accessories need upgrades and improvements.
Mount Is Prone to Error
The wobbly tripod is the most problematic part.
The accessories all need upgrades except the finder.
The GoTo mount is not as reliable as any manual telescope model. It is more prone to error, and the repair process is more difficult.
There are not many problems within the package of StarNavigator 90 NG, but the existing ones are major. A telescope should be close to its potential out of the box, and the accessories that come with StarNavigator 90 NG Refractor prevent it from rising to that level.
If you are willing to spend some time and money upgrading the tripod and accessories, StarNavigator 90 NG Refractor is a good choice. If not, I recommend checking out Dobsonian’s at this price range. They will provide the most value.