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Questions & Answers
What is the aperture Expert Answer

The large primary mirror is 135mm in diameter and in mounted in a heavy-duty mirror cell.

by Tom B, Gear Expert, October 15, 2021
Customer Reviews
Helpful Positive Review
Great way to view the night sky by Gary, February 23, 2022
This is an amazing telescope. It is very well constructed, heavy materials and a built-in leveling bubble. The addition of the color filter wheel makes viewing Nebula and planets much better by filtering out light bands that hamper viewing. Getting...
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Color: Black Finish: Black Objective Lens Diameter: 135 mmFocal Length: 900 mmFinderscope: Mars Eye Electronic Finderscope Optical Coating: Fully Multi-Coated Condition: New Included Accessories: 1-1/4in 10mm Plossl Eyepiece , 1-1/4in 25mm Astroscopic Eyepiece , Accessory Tray , Cassini Planetarium PC CD-ROM , Mars Eye Finderscope , Pre-Assembled Metal Tripod , Two-Element 3x Astroscopic Barlow Lens

Code: ZC-TS-CASSTELES2-C-900135TRCFW

MPN: C-900135TRCFW

UPC: 851514006961

Product No Longer Available

Product Info for Cassini 900mm x 135mm C-900135TR Tracker Reflector Telescope

The Cassini C-900135TRCFW telescope with free Color Filter Wheel is mounted on Cassini's new Tracker altitude/azimuth mount. It's easy to use up and down, left and right movement allows tracking an object with unprecedented precision using both manual macro adjustments for aiming your telescope and manual micro adjustments for precise observing and tracking. The C-900135TR includes Cassini's sturdy, fully adjustable, pre-assembled metal tripod featuring an accessory tray with slots to place 4 1" eyepieces or lenses and retractable rubber feet. The C-900135TRCFW features a 900mm focal length. The large primary mirror is 135mm in diameter and in mounted in a heavy-duty mirror cell. The finder is Cassini's Mars-Eye Electronic Finder which helps by getting the observer behind the telescope without losing the surrounding field of view when targeting objects. Included with the C-900135TRCFW are a 1" 10mm Plssl eyepiece, a 1" 25mm Eyepiece, and a 2 element 3x Barlow. Youll also get a free Cassini Color Filter. Filtering out certain bands of light can be very useful when observing astronomical objects. With the Cassini Color Filter Wheel, you simply switch eyepieces as you normally would. To switch filters, just rotate the dial on the Cassini Color Filter Wheel. The C.F.W. has three filter settings: Nebula, Planetary and Clear. The Nebular filter is great for filtering out light pollution such as ground light. UHC filters block a large fraction of light pollution and bring out the details of nebulae. The Planetary filter is great for viewing the moon and planets by increasing contrast. 3rd slot is Empty to use additional filter of your choice or left empty so objects can be viewed normally without having to remove the Color Filter Wheel. Additionally, the filters are universal 1.25 threaded filters so you can switch them out with other filters for more usability. Lastly, the Cassini Stellarium CD ROM brings you the skies over your home or anywhere in the world.image

Features of Cassini 900mm x 135mm C-900135TR Tracker Reflector Telescope

  • Cassini TRACKER mount w/Slow Motion Vertical & Horizontal Manual Controls
  • 900mm x 135mm Optical Tube Assembly
  • Diffraction limited Optical Tube Assembly (?4)
  • Fully Adjustable Heavy Duty, Pre-assembled Metal Tripod w/Accessory Tray
  • Cassini Mars Eye Electronic Finderscope
  • 1" Helical Rack & Pinion Focusing
  • 1" 10mm Plssl Eyepiece
  • 1" 25mm Astroscopic Eyepiece
  • 1" 3x 2-Element Astroscopic Barlow
  • Cassini Stellarium CD-ROM
  • The Cassini Color Filter Wheel Features and Benefits:
  • Format: 1.25?
  • 3 Filter Settings: Nebula, Planetary, and Empty/Clear
  • Universal 1.25? slots for Filter Switching
  • Rotating Bezel Metal Construction

Package Contents:

  • Cassini 900mm x 135mm C-900135TR Tracker Reflector Telescope
  • Fully Adjustable Heavy Duty Pre-assembled Metal Tripod w/Accessory Tray 1" 10mm Plssl Eyepiece 1" 25mm Astroscopic Eyepiece 1" 3x 2-Element Astroscopic Barlow Cassini Stellarium CD-ROM Cassini Color Filter Wheel 1.25? - 3 Filter Settings: Nebula Planetary and Empty/Clear

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List of Unorderable Models

  • Cassini C-900135TR 900mm x 135mm Tracker Reflector Telescope w/Color Filter Wheel, Black, NSN N, C-900135TRCFW , MPN: C-900135TRCFW , UPC: 851514006961 , Code: ZC-TS-CASSTELES2-C-900135TRCFW
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