Celestron Ultima 80 - Manual (Page 16)

S S P P E E C C I I F F I I C C A A T T I I O O N N S S
#21048
Optical System: Refractor
Aperture: 80mm (3.1")
Focal Length: 900mm
F/ratio: f/11
Focuser
Rack and Pinion
Standard Oculars (or
Eyepieces) 20mm 1¼" (45x)
4mm 1¼" (225x)
3x Barlow (135-675x)
Resolution 1.7 arc seconds
Light gathering Power 131x unaided eye
Limiting Magnitude 12
Highest useful Power 189x
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.
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.
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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.
Ultima - Ultima is our 5-element, wide field eyepiece design. In the 1-1/4" barrel
diameter, they are available in the following focal lengths: 5mm, 7.5mm, 10mm, 12.5mm,
18mm, 30mm, 35mm, and 42mm. These eyepieces are all parfocal.
Axiom – As an extension of the Ultima line, a new wide angle series is offered – called the Axiom series. All units
are seven element designs and feature a 70º extra wide field of view (except the 50mm). All are fully multicoated
and contain
all the features of the Ultimas.
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