Meade 90mm ETX Maksutov-Cassegrain

The 90mm (3.5″) Meade ETX is a wonderful little telescope that I use for eclipses and spur of the moment observing sessions in my backyard. It has an electric RA motor drive for tracking objects. The scope is easy to set up and operate. I have the older “RA” version of this scope that doesn’t have the Go-To function or object database controller.  So to use it you manually find an object and lock down the RA drive to track that object.  I have taken great quality images with this telescope by digiscoping, using a Meade T-Adapter #64 for prime-focus imaging with a DSLR and also piggy-backing a DSLR such as seen in the images below. Here are images taken with the ETX via digiscoping.  Here you’ll find images taken using the prime-focus method. Finally, here are images taken while employing the piggy-back method.

Specifications and Features of the 90mm Meade ETX

Optical Design: Maksutov-Cassegrain
Aperture: 90mm (3.5″)
Focal Length: 1250mm
Focal Ratio: f/13.8
Resolving Power (arc secs.): 1.3
Optical Coatings: MgF2; standard aluminum/SiO
Limiting Visual Magnitude: 11.7
Maximum Practical Visual Power: 325X
Secondary Mirror Obstruction (dia.; %): 1.1″ (27.9mm); 9.6%
Telescope Mounting: fork type; double tine
Primary Mirror Correcting Lens: Pyrex ® glass, BK7 optical glass, Grade-A
Finder Scope: 8 x 20mm right-angle viewfinder
Tripod: Deluxe field tripod
Total Net Telescope Weight: 19 lbs.

Meade ETX 90RA Instruction Manual – PDF

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