2 • Introduction
Your G-8 telescope is designed to give you hours of fun and rewarding observa-
tions. However, there are a few things to consider before using your telescope
that will ensure your safety and protect your equipment.
WARNING !
NEVER LOOK DIRECTLY AT THE SUN WITH THE NAKED EYE OR WITH A
TELESCOPE. PERMANENT AND IRREVERSIBLE EYE DAMAGE MAY
RESULT.
NEVER USE YOUR TELESCOPE TO PROJECT AN IMAGE OF THE SUN
ONTO ANY SURFACE. INTERNAL HEAT BUILD-UP CAN DAMAGE THE
TELESCOPE AND/OR ANY ACCESSORIES ATTACHED TO IT.
NEVER USE AN EYEPIECE SOLAR FILTER OR A HERSCHEL WEDGE.
INTERNAL HEAT BUILD-UP INSIDE THE TELESCOPE CAN CAUSE THESE
DEVICES TO CRACK OR BREAK, ALLOWING UNFILTERED SUNLIGHT TO
PASS THROUGH TO THE EYE.
NEVER LEAVE THE TELESCOPE UNSUPERVISED, EITHER WHEN CHIL-
DREN ARE PRESENT OR ADULTS WHO MAY NOT BE FAMILIAR WITH
THE CORRECT OPERATING PROCEDURES OF YOUR TELESCOPE.
NEVER POINT YOUR TELESCOPE AT THE SUN UNLESS YOU HAVE THE
PROPER MYLAR SOLAR FILTER. WHEN USING YOUR TELESCOPE WITH
THE CORRECT SOLAR FILTER, ALWAYS COVER THE FINDER. AL-
THOUGH SMALL IN APERTURE, THIS INSTRUMENT HAS ENOUGH LIGHT
GATHERING POWER TO CAUSE PERMANENT AND IRREVERSIBLE EYE
DAMAGE. IN ADDITION, THE IMAGE PROJECTED BY THE FINDER IS HOT
ENOUGH TO BURN SKIN OR CLOTHING.
A telescope is an instrument that collects and focuses light. The nature of the
optical design determines how the light is focused. Some telescopes, known
as refractors, use lenses while others, known as reflectors, use mirrors. The
Schmidt-Cassegrain optical system (or Schmidt-Cass for short) uses a
combination of mirrors and lenses and is referred to as a compound or cata-
dioptric telescope. This unique design offers large diameter optics while
maintaining very short tube lengths, making them extremely portable. The
Schmidt-Cassegrain system consists of a zero power corrector plate, a
spherical primary mirror, and a secondary mirror. Once light rays enter the
optical system, they travel the length of the optical tube three times.
Inside the optical tube you will notice a black tube (not illustrated) that extends
out from the center hole in the primary mirror. This is the primary baffle tube
and it prevents stray light from passing through to the eyepiece or camera.
A Word of Caution
The Schmidt-
Cassegrain
Optical System
