Technical Specifications; Optional Accessories - Celestron Firstscope 80 AZ Instruction Manual

Technical Specifications
Below is pertinent technical information on your Firstscope AZ telescope
that you may find useful.
Firstscope 80 - AZ
Optical System: Refractor-Achromat
Firstscope 102 - AZ
Refractor-Achromat
Aperture:
80mm (3.14")
102mm (4")
Focal Length:
900mm (35.4")
500mm(19.7")
Highest Useful Power
Magnification:
189x
24Qx
Resolution (arc seconds) -
Dawes:
1.45
1.14
Light Gathering Power:
131x
212x
Limiting Visual Magnitude:
12.0
12.5
Angular Field of View in Degrees
(with 20mm eyepiece):
1.2°
2.0°
Linear Field of View
(with standard eyepiece):
63'
105'
F/ratio:
f/11
175
Length:
36"
21"
Weight:
Optical Tube:
5.5 lb.
51b.
With Tripod:
181b.
17.51b.
All specifications are stated for the telescope using the standard accessories.
These specifications are approximate and subject to change without notice.
Note
Celestron offers a large assortment of accessories for this telescope:
. . Barlow
Lens - A Barlow lens is a negative lens that increases the focal length of a
Optional Accessories
telescope. Used with any eyepiece, it doubles the magnification of that eyepiece.
Celestron offers two Barlow lens in the 1-1/4". 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. Model #93507 is a compact achromatic
Barlow lens that is under three inches long and weighs only 4oz. It works very well with
all Celestron eyepieces.
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.
• Super Modified Achromatic (SM A) Eyepieces: 11/4". The SMA design is an improved
version of the Kellner eyepiece. SMAs are very good, economical, general purpose
eyepieces that deliver a wide apparent field, good color correction and an excellent
image at the center of the field of view. Celestron offers SMA eyepieces in 1 -1/4" sizes
in the following focal lengths: 6mm, 10mm, 12mm, 17mm and 25mm.
•Plossl-Plossl eyepieces have a4-element lens designed for low-to-high power observing.
The Plossls 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: 3.6mm, 6mm,
8mm, 10mm, 13mm, 17mm, 25mm, 32mm and 40mm.
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