Celestron 70 manual Specifications, Optional Accessories, #21076, #21085

Models: 70

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SPECIFICATIONS

SPECIFICATIONS

 

#21076

#21085

Optical System:

Refractor

Refractor

Aperture:

70mm (2.8")

90mm (3.5")

Focal Length:

900mm

1000mm

F/ratio:

f/13

f/11

Focuser

Rack and Pinion

Rack and Pinion

Standard Oculars (or

20mm 1¼" (45x)

20mm 1¼" (50x)

Eyepieces)

10mm 1¼" (90x)

10mm 1¼" (100x)

Resolution

1.7 arc seconds

1.3arc seconds

Light gathering Power

100x unaided eye

165x unaided eye

Limiting Magnitude

11.4

12.3

Highest useful Power

142x

213x

NOTE: Specifications are subject to change without notice.

OPTIONAL ACCESSORIES

You will find that additional accessories enhance your viewing pleasure and expand the usefulness of your telescope. For ease of reference, all the accessories are listed in alphabetical order.

Barlow Lens - A Barlow lens is a negative lens that increases the focal length of a telescope. Used with any eyepiece, it doubles the magnification of that eyepiece. Celestron offers two Barlow lens in the 1-1/4" size. The 2x Ultima Barlow (#93506) is a compact triplet design that is fully multicoated for maximum light transmission and parfocal when used with the Ultima eyepieces. The OMNI Barlow (#93326) is a compact achromatic Barlow lens that is under three inches long and weighs only 4 oz. It works very well with all Celestron eyepieces.

Exotherm (#93504)- Perfect for chilly evenings outdoors camping, stargazing, or at sporting events, the Exotherm hand warmer is convenient, reusable and made from nontoxic materials. Heat lasts up to 1 hour.

Eyepieces - Like telescopes, eyepieces come in a variety of designs. Each design has its own advantages and disadvantages. For the 1-1/4" barrel diameter there are four different eyepiece designs available.

OMNI Plössl - Plössl eyepieces have a 4-element lens designed for low-to-high power observing. The Plössls offer razor sharp views across the entire field, even at the edges! In the 1-1/4" barrel diameter, they are available in the following focal lengths: 4mm, 6mm, 9mm, 12.5mm, 15mm, 20mm, 25mm, 32mm and 40mm.

X-Cel- This 6 element design allows each X-Cel Eyepiece to have 20mm of eye relief, 55° field of view and more than 25mm of lens aperture (even with the 2.3mm). In order to maintain razor sharp, color corrected images across its 55° field of view, extra-low dispersion glass is used for the most highly curved optical elements. The excellent refractive properties of these high grade optical elements, make the X-Cel line especially well suited for high magnification planetary viewing where sharp, color-free views are most appreciated. X-Cel eyepiece come in the following focal lengths: 2.3mm, 5mm, 8mm, 10mm, 12.5mm, 18mm, 21mm, 25mm.

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Celestron 70 manual Specifications, Optional Accessories, #21076, #21085