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Coronado SolarMax II 90 RichView Tuning Telescope – Review

Last Updated: 06.12.21


Main technical features


From the leader in solar day time observing comes the Coronado SolarMax II 90 SMT90DS-30, which demonstrates a breakthrough in the industry with the cutting-edge RichView tuning assembly. This exceptional patented system works as a fully integrated stacking unit with the extra advantage of being able to run at a less restrictive < 0.7A bandwidth because of the simple elimination of the external etalon. The etalon filter is composed of optics with four times tighter tolerances compared to what are in the Hubble telescope.

Meade has also included the exclusive Coronado Sol Ranger Sun Finder. This revolutionary finder scope sits on top of the clamshell and enables the projection of a small and harmless ball of light onto the opaque glass at the back end. This enables you to center this ball of light in the glass while standing back from the Sol Ranger and with the telescope aligned with the sun without putting your eye up against the opaque glass. The helical focuser is adjusted when the sun is in the field of view, the draw tubes are extended, the eyepiece has been inserted into the eyepiece retainer and the thumbscrew has been securely tightened. This makes the solar telescope fairly easy to use.

This premium quality 90mm telescope becomes your very own personal solar observatory with its 800mm focal length, f/8.8 focal ratio and other useful accessories including the Cemax eyepieces and travel case. The clamshell mounting ring is designed for compatibility with any ¼ 20 thread and can be used with most mounting hardware and photographic mounts for a reliable, secure and safe rig, and also supports piggyback mounting systems.


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In-depth information


As a fully integrated 90mm H-alpha telescope, this model is the largest one ever to be mass-produced and even comes with the RichView tuning system that enables it to provide fantastic views of the solar surface detail, thanks to the less restrictive < 0.7A bandpass. Used by avid solar astronomers and professional research institutions to observe surface prominences and detail on the sun using hydrogen-alpha (Ha) light, this is a superbly powerful yet easily portable solar telescope that can offer premium quality imaging along with dedicated visual solar observation. With its RichView tuning assembly, this telescope allows the direct tuning of the primary filter etalon, ensuring exceptional tuning range and accuracy, with excellent image brightness and enhanced visibility of fainter limb detail.

The Sol Ranger sun finder, which is standard equipment with this model, gives you a more effortless means of centering the device on the sun’s image without endangering your eyes. A passive solar finder, the Sol Ranger enables safe and easy centering of the image of the sun in the eyepiece. It is a metallic tube equipped with a pinhole aperture facing the sun in the back end, at the opposite end of which is a translucent viewing screen. It bolts to predrilled holes in the supplied clamshell scope mounting ring and once bolted, aligns automatically with the scope’s optics to eliminate the need for collimation. A discrete solar disk image will be on the viewing screen once the scope has been directly pointed at the sun.

The Cemax eyepieces boast high quality machining with knurled rubber grips on the sides of their barrels. They also come with a short rubber eyecup on the eye end and are threaded for standard 1.25-inch filters. The mounting rings simplify alignment of the sun in the main scope in just seconds. The f/8.8 focal ratio, 800mm focal length, and Cemax eyepieces work together to give a more detailed look so you can easily tune the telescope for high contrast views of active regions, filaments, flares and other interesting surface detail. They also allow quick and easy retuning for prominences on the solar limb. With the stunning bright red views the telescope delivers, you can observe remarkable limb and surface detail with the sun in its active phase.


Known issues

This amazing telescope has had no known issues until this time. This means customers have had no Cons to report while using the device.


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Ioana Moldovan

Ioana’s professional experience in the optics field has helped her understand the value of passing her knowledge forward. Her curious personality helps her gather useful information for her readers and her goal is to make technical information fun and accessible to everyone.

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