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Takahashi - Sky 90II 90mm 3.5" f/5.6 Fluorite Refractor Apochromatic Telescope - (EM-11 Temma IIM Mount) - DISCONTINUED


Discontinued Product

Manufactured by: Takahashi


Takahashi Sky 90II Fluorite Refractor


  • 90mm f/5.56 Fluorite APO refractor yields beautiful,high-contrast views.
  • OTA weighs only 7 lbs., great travel scope.
  • EM-11 Temma II, Jr. is a GoTo Mount that can handle a payload of up to 25 lbs.
  • 10 arc-second or better tracking accuracy.
  • Now comes with BT Technologies finder bracket quick release!
  • Includes wooden tripod with Shimano Clamps.


The latest telescope model from Takahashi is a truly portable design. The 90mm (3-1/2") f/5.56 fluorite doublet apochromatic optical system is of outstanding quality, with a focal length of 504mm. The optical tube assembly is only 13.8" long and weighs 7 pounds; small enough for an airline 'carry-on'.

Not only is this instrument an excellent choice for astronomy, it can be used as a portable high-quality telescope for birding. The oversize focuser has an adapter for 2" and 1-1/4" diagonals, and accepts the FS series photographic adapters.


Features for the EM-11 Temma II, Jr. Mount: 

  • Drive System: Dual axes, quartz control, driving frequency: 100pps N/S, Star/Sun switching by hand controller
  • Useable Area: All over the world, but with limit for the latitude
  • High Speed Drive: 120X at DC12V, 250X at DC24V
  • Correcting Speed (Manual Operation): RA: 0.1 ~ 1.9x to the sidereal rate by 0.1X increments. Dec: +/- 1.5 ~ 13.5 arc sec/sec by 1.5 arc sec/sec increments
  • Mode Indicator: High speed operation - red light. Normal operation: green light
  • Power Source: DC12V or DC24V
  • Power Consumption: DC12V: 0.3/1.3A (1.7A) sidereal/high speed (start). DC24V: 0.3/1.9A (1.9A)
  • Operational Temperature: -5 ~ +30ºC
  • Go-To Operation: By a PC or Takahashi hand controller (THC)
  • Go-To Disc: Pegasus 21
  • Accessory: RS232C cable or RJ-11 cable


Included Items for Sky-90 II - 3.54" f/5.6 APO Refractor on EM-11 Temma II, Jr. Mount:

  • FCL-90 Tube Assembly
  • EM-11 Temma II, Jr. Mount
  • FC-L Wooden Tripod w/ Shimano Clamps
  • Tube Holder
  • 6X30 Finder
  • Finder Bracket
  • BT Technologies Finder Bracket Quick Release
  • 18mm LE Eyepiece (1.25")
  • 1.25" Compression Ring Diagonal



Additional Information

Name Takahashi - Sky 90II 90mm 3.5" f/5.6 Fluorite Refractor Apochromatic Telescope - (EM-11 Temma IIM Mount) - DISCONTINUED
Manufacturer Takahashi
Model TSS9033
Discountinued Yes
Custom Stock Status Out of Stock
Aperture 90mm (3.54")
Counterweights 1 - 7.7 lb
Diameter 3.7"
Focal Length 19.8" (504mm)
Focal Ratio f/5.56
Focuser Rack & Pinion
Limiting Stellar Magnitude 11.5
Motor Drive Motorized with GoTo Capabilities
Mount German Equatorial
Mount Weight 24.2 lbs
Optical Coatings Fully Muli-Coated
Optical Design Apochromatic Fluorite Doublet Refractor
Optical Tube Length 14.5"
Optical Tube Weight 7 lbs