User manual MEADE ETX-90EC

[. . . ] Instruction Manual ETX-90EC Astro Telescope ETX-105EC Astro Telescope ETX-125EC Astro Telescope Meade Instruments Corporation CONTENTS WARNING! Never use a Meade® ETX® Astro Telescope to look at the Sun!Looking at or near the Sun will cause instant and irreversible damage to your eye. Eye damage is often painless, so there is no warning to the observer that damage has occurred until it is too late. Children should always have adult supervision while observing. Quick-Start Guide . [. . . ] For through-the-telescope photography, turn the flip-mirror control (5, Fig. 18) to the "down" position, allowing light to pass straight through the telescope and out the photo port (15, Fig. With the flip-mirror control in the "down" position and the photo port's dust cover removed, you can see the front lens of the telescope when you look through the photo port. The #64 T-Adapter threads onto the photo port, followed by a T-mount for the particular brand of 35mm camera being used, followed by the camera body (with the camera lens removed). You may use either of the following photographic mounting formats to couple the camera body to the telescope's photo port thread. · Format 1: Camera Body + T-Mount + Section (1) of the #64 T-Adapter (7, Fig. ETX-90EC ETX-105EC ETX-125EC 1250mm at f/13. 8 1640mm at f/15. 6 1900mm at f/15 Format 1 utilizes only the short section of the #64 T-Adapter to permit close-coupling of a camera body to the telescope. In this format vignetting will occur: the photographic image will appear on film with a slight darkening at the corners of the 35mm frame (see Fig. · Format 2: Camera Body + T-Mount + Sections (1) and (2) of the #64 T-Adapter (see Fig. ETX-90EC ETX-105EC ETX-125EC 1450mm at f/16 1830mm at f/17. 4 2310mm at f/18 - 18 - Format 2 utilizes both sections of the #64 T-Adapter threaded together to form a rigid unit. In this configuration there is no field vignetting: images are illuminated to the edges of a standard 35mm frame (see Fig. To frame an object in the viewfinder of the 35mm camera body, slightly loosen the knurled attachment ring (3, Fig. 18), which threads the #64 TAdapter to the telescope's photo port; rotate the camera body to achieve proper framing of the object; then retighten the knurled ring. 2 1 7 3 6 4 5 Fig. 18: Example of photography through the ETX using the Photography through a long lens, such #64 T-Adapter: (1) Short section of #64 T-Adapter; as the ETX, requires special technique (2) Extension section of #64 T-Adapter; (3) Knurled attachment for good results. The photographer ring; (4) T-mount; (5) Flip-mirror control in "down" position; (6) should expect to use a roll or two of 35mm camera body; (7) Format 1. Longlens photography has its own rewards, however, which short-focus lenses cannot duplicate. Use the optional table tripod specific to your model of ETX, or the #883 Deluxe Field Tripod as a platform for the telescope. At effective focal lengths of 1250mm to 1450mm (ETX-90EC), 1640mm to 1830mm (ETX-105EC), or 1900mm to 2310mm (ETX­125EC), even small external vibrations can easily ruin an otherwise good photo. CAUTION: With the #64 T-Adapter and a camera body mounted to the ETX photo port, the telescope can be rotated vertically only 45°. Touching the camera body to operate the shutter will almost certainly introduce undesirable vibrations. While observing the subject through the camera's reflex viewfinder, turn the ETX's focus knob (8, Fig. Note that some 35mm cameras may have an optional focusing screen (available from the manufacturer) for use with a long telephoto lens. [. . . ] To learn the constellations, start with an easy grouping of stars, such as the Big Dipper in Ursa Major. Galaxies are large assemblies of stars, nebulae, and star clusters that are bound by gravity. The most common shape is spiral (such as our own Milky Way), but galaxies can also be elliptical, or even irregular blobs. The Andromeda Galaxy (M31) is the closest spiraltype galaxy to our own. [. . . ]