Celestron Astro Fi 90mm Refractor Telescope

Item #298236

Shipping Included
Includes: Telescope Optical Tube Assemblies (OTA), Mount/Tripod, 2 x Eyepieces, Accessory Tray, 1.25" Star Diagonal, Battery Pouch and the Free SkyPortal App

Your estimated delivery time will be 7 business days (excluding weekends and bank holidays) from the time of order. Postcode Restrictions may apply. Find out more in the Delivery & Returns Tab below.


Instruction manual

The Celestron Astro Fi 90 is a computerised altazimuth refractor telescope offering spectacular views of craters on the moon, the rings of Satern and many planets and stars. The Celestron Astro Fi 90 also comes with a star diagonal erecting lens providing right side viewing to use as a spotting scope during daylight. The lens cap can also be used as a smartphone adapter meaning you are able to place your smartphone inside the adapter securing it over the eyepiece in order to capture images and videos of all your findings in the sky. 

Fitted with sky align technology you are able to centre any three bright objects in the eyepiece and your telescope will calculate its position. With the two eyepieces, one 25mm and the other 10mm, you can observe the sky at different magnifications meaning you are able to view anything you like with ease. Compatible with Celestron's Starry Night Software where you can learn and discover the night sky, celestial objects and planning observing sessions for optimum results. 

Refractor Telescope:

A refractor telescope is the traditional expectation of what a telescope looks like. It features a long tube with an objective lens located at the front and the eyepiece at the back. Focusing takes place at the rear of the telescope, while the front objective lens refracts the light gathered to form a crisp and high contrast image in the eyepiece. Refractor lenses are a rugged design with a sealed tube, making this the perfect choice for those new to star gazing and younger users. Refractors excel at moon and planetary observations, however are also capable of viewing stars.

Altazimuth Mount:

An Altazimuth mount or “AZ” is a simple design using two axises to support or rotate the telescope, restricted to up, down, left or right motions. Its simple design makes this mount easy to use and allows a quick manual adjustment by the user. The simplicity of use makes this mount a great choice for a beginner’s telescope, or as a secondary instrument for quick and easy use. The limitation of this type of mount is if you are planning to view one object all evening, constant small adjustments in all directions will be needed, as the stars and planets rise and set in the sky like the sun.


  • High quality 90mm refractor lens telescope
  • Integrated Wi-Fi using the free Celestron skyPortal app for iPhone, iPad, and Android devices
  • Observe in no time with a quick and easy, no-tool setup
  • Includes star diagonal, finderscope, and a integrated smartphone adapter
  • Adjustable height tripod includes an accessory tray
  • Optical Coatings: Fully-coated
  • Optical Design: Refractor
  • Aperture: 90mm (3.54")
  • Focal Length: 910mm (36")
  • Focal Ratio: f/10.1
  • Focal Length of Eyepiece 1: 25mm (.98"); Magnification: 36x
  • Focal Length of Eyepeice 2: 10mm (.39"); Magnification: 91x
  • Finderscope: StarPointer
  • Star Diagonal: 1.25"
  • Light Gathering Power: (compared to human eye) 165x
  • Slew Speeds: Up to 3°/second
  • Mount Type: Computerised Altazimuth

Magnification36x / 91x
DimensionsL 110.2 x 25.1 x 39.1 cm
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