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William Optics SpaceCat APO f/4.9 Refracting Telescope - Limited Edition - L-RC51TG

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William Optics has discontinued the Limited Edition SpaceCat 51 APO f/4.9 Refracting Telescope, and we are out of stock. Here is a link to the William Optics RedCat 51 APO f/4.9 Refracting Telescope we carry at High Point. Hopefully, you can find a proper replacement in this selection. If we can be of further assistance, please don't hesitate to call us at 1-800-266-9590 or send an email, and we will be happy to help you. Thank you!

William Optics Limited Edition SpaceCat 51 APO f/4.9 Refracting Telescope

The William Optics Cat Series Refractor is just getting better!

If you are looking for a great refracting telescope that helps you capture images of wildlife or the night sky, then the William Optics SpaceCat could be the scope you've been looking for. This limited edition of the William Optics RedCat is now gray and has a customized case!

The William Optics SpaceCat has an aperture of 51mm, a focal length of 250mm and a fast f/4.9 focal ratio making it lightweight and super portable.

When it comes to camera compatibility, the SpaceCat knows how to deliver. This refractor comes with 48 mm threads which accept a variety of wide T-mounts, from Canon to Nikon, Sony E to Pentax, or Micro 4/3. The T-Mount compatibility along with the camera sensor tilt adjuster makes this refractor an ideal astrophotography instrument. You can also put a diagonal and eyepiece on the back for spectacularly sharp, high contrast images of both terrestrial and celestial targets. Mount the William Optics SpaceCat on a photographic tripod or an equatorial mount with the reversible base that has Arco-Swiss mounting on one side and a standard Vixen dovetail on the other. That’s just the beginning, though! Check out all the features of this flexible APO refractor that can do triple duty as a camera lens, a spotting scope, or a telescope:

Amazing Optics

The William Optics SpaceCat 51 sports optics made of Ohara FPL53 & FPL51 synthetic fluorite glass for beautiful high contrast, spectacularly sharp results when used in both visual and photographic applications. APO performance means you’ll have virtually zero chromatic aberration. The Petzval design, which consists of four elements in three groups, also known as a Quad, produces a full frame flat field, with a image circle of 44 mm.

Thoughtful and Innovative Design

Let’s start at the front and work our way back! The SpaceCat body is made of a strong aluminum alloy and is anodized a beautiful gray for strength and durability. A matching dew/sun shield can be attached when needed and then inverted to store the lens without the additional length the dew shield provides. An aluminum threaded cap protects the optics whenever the SpaceCat is not in use.

In the middle of the SpaceCat 51, you will find a nicely designed ring mount that attaches to the reversible base and wraps securely around the body of the lens. A gray anodized knob allows you to loosen the ring enough to fully rotate the SpaceCat 51, and of course, it is also used to lock the ring in place. The “ring” has a flat section that has two 1/4-20 holes spaced far enough to allow the addition of a red dot finder, microphone, or other compatible accessories.

Calibrated Helical Focuser with 360-Degree Rotator

The helical focuser on the SpaceCat is engraved with calibration markings, and a focus tension ring allows you to lock focus or just increase or decrease the drag to your liking. A field rotator is included with this 250 mm lens as well, and every degree is plainly marked…all 360 of them! William Optics says they were inspired by luxury watches when they designed this rotator, but what it means to you is mosaics of large celestial objects or sections of the sky will be much easier!

A filter slot is built into the OTA just after the rotator and accepts 48 mm filters, and the back of the SpaceCat is fitted with M48 threads. Attach a full-frame (M48) M 4/3, Nikon, Canon, Sony, or Pentax T-ring to the threads and use your DSLR to produce beautiful images. Or, attach a diagonal and eyepiece and turn this 250 mm f/4.9 beauty into a telescope or spotting scope.

Includes These Accessories

You will also receive a Bahtinov Mask for focusing assistance during astrophotography (that might give you a hint as to why the Cat’s whiskers look like they do…just look at the threaded cap), the M48 camera mount (T-ring mentioned above not included) and a soft carry case. Aluminum covers are also included for the front and back of the telescope.

William Optics SpaceCat 51mm Petzval APO Refractor Telescope Specs

  • Telescope Series: William Optics SpaceCat
  • Optical Design: Refractor
  • Refractor Design: Apochromat (APO)
  • Number of Refractor Elements: 4
  • Aperture: 2" (51mm)
  • Focal Ratio: f/4.9
  • Focal Length: 250mm
  • Focuser Style: Helical
  • OTA Length - Retracted: 8.3" (210mm)
  • OTA Weight: 2.9lbs
  • Image Circle Size: 44mm

Please Note : While the diagonal is not included with the SpaceCat, you can purchase it separately and use the instructions listed above in the picture list to properly install it.