Company Seven Astro-Optics Division REPRINT OF THE Celestron Celestron 8 Telescope Instruction Manual Originally Printed September 1995 From Company Seven Archives Reprint ©1995 Celestron Int'l., P/N 11015-1 All Rights Reserved December 2000 Showroom: 14300 Cherry Lane Court Laurel, Maryland 20707 301-953-2000 http://www.company7.com Correspondence: Box 2587 Montpelier, Maryland 20709-2587 info@company7.
CELESTAR INSTRUCTION MANUAL 1
TABLE OF CONTENTS INTRODUCTION......................................................................................................................................... 5 HOW TO USE THIS MANUAL ............................................................................................................................ 5 A WORD OF CAUTION ......................................................................................................................................
Celestar Manual Outlets....................................................................................................................................................... 38 The Hand Controller (Optional Accessory) .............................................................................................. 38 NORTHERN/SOUTHERN HEMISPHERE OPERATION ......................................................................................... 39 CHANGING THE BATTERY .........................................
Celestar Manual TECHNICAL SPECIFICATIONS............................................................................................................ 78 FURTHER READING ...............................................................................................................................
Celestar Manual INTRODUCTION Welcome to the Celestron world of amateur astronomy! For more than a quarter of a century, Celestron has provided amateur astronomers with the tools needed to explore the universe. The Celestar line of telescopes continue in this proud tradition combining large aperture optics with ease of use and portability. With a mirror diameter of 8 inches, your Celestar telescope has a light gathering power of 841 times that of the unaided human eye.
Celestar Manual A WORD OF CAUTION Your Celestar telescope is designed to give you hours of fun and rewarding observations. There are, however, 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.
Celestar Manual THE SCHMIDT-CASSEGRAIN OPTICAL SYSTEM A telescope is nothing more than 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 (or Schmidt-Cass for short) system uses a combination of mirrors and lenses and is referred to as a compound or catadioptric telescope.
Celestar Manual ASSEMBLING YOUR CELESTAR The complete line of Celestar models are fork mounted telescopes with built-in single motor gear drives. The Celestar 8 and Celestar 8 computerized have a spur gear drive powered by a single 9-volt battery while the Celestar Deluxe 8 and Celestar Deluxe 8 computerized are worm gear driven powered by two 9-volt batteries. All models can also run off external AC or DC power.
Celestar Manual Figure 2-1 -- Celestar 8 Figure 2-2 -- Celestar8 Deluxe Assembling your Celestar 9
Celestar Manual SETTING UP THE TRIPOD (For Celestar Deluxe 8 And Celestar Deluxe 8 Computerized Only) For maximum rigidity, the Celestron field tripod has a leg support bracket. This bracket fits snugly against the tripod legs, increasing stability while reducing vibration and flexure. However, the tripod is shipped with each arm of the leg support bracket in between the legs so the tripod legs can collapse. To set up the tripod: 1. Hold the tripod with the head up and the legs pointed toward the ground.
Celestar Manual ADJUSTING THE TRIPOD HEIGHT (For Celestar Deluxe 8 And Celestar Deluxe 8 Computerized Only) The tripod that comes with your Celestar Deluxe 8 telescope is adjustable. To adjust the height at which the tripod stands: 1. Loosen the extension clamp on one of the tripod legs (see figure 2-3). 2. Extend the leg to the desired height. 3. Tighten the extension clamp to hold the leg in place. 4. Repeat this process for each of the remaining legs.
Celestar Manual W edge Bolts Threaded Holes Tripod Figure 2-4 SETTING UP THE WEDGPOD (For Celestar 8 And Celestar 8 Computerized Only) The Wedgpod comes pre-assembled. Just remove it from the box, stand it up, and separate the tripod legs. There are stops that set the proper angle of the legs. LATITUDE ADJUSTMENT Before attaching the telescope to the wedge/Wedgpod, you must adjust the wedge/Wedgpod to the proper latitude. To do so: 1.
Celestar Manual 1. Lay the telescope on its side and locate the three threaded holes in the bottom of the drive base. 2. Partially thread one of the three 3/8"-16 bolts (supplied in the bolt pack) into the hole that is opposite the rectangular portion of the base. 3. Pick the telescope up by the fork tines and position it above the tripod. It should be oriented so that the telescope is over the tripod with the base pointing toward the tilt plate. 4.
Celestar Manual 9x50, stand for the magnification and the aperture, in millimeters, of the scope. So, a 6x30 finder magnifies six times and has a 30mm objective lens. To ensure that the finder and bracket are not damaged during shipping, they are not attached to the telescope at the factory. Start by removing the finder and hardware from the plastic wrapper.
Celestar Manual ATTACHING THE FINDER TO THE BRACKET With the bracket firmly attached to the telescope, you are ready to attach the finder to the bracket. 1. Thread the three nylon thumbscrews into the finder bracket. Tighten the screws until the heads are flush with the inner diameter of the bracket ring. Do not thread them in completely or they will interfere with the placement of the finder. 2. Slide the rubber O-ring onto the back (i.e., eyepiece end) of the finder.
Celestar Manual INSTALLING THE VISUAL ACCESSORIES Installing the ocular and other visual accessories is the same for both the Celestar 8 and Celestar Deluxe 8. The Visual Back The visual back allows you to attach most visual accessories to the telescope. If you use a 1-1/4" star diagonal or if you want to insert the eyepiece into the telescope without a diagonal, then attach the visual back to the rear cell on the back of the telescope (see Figure 2-8). To attach the visual back: 1.
Celestar Manual The Eyepieces The eyepiece, or ocular, is the optical element that magnifies the image focused by the telescope. The eyepiece fits either into the visual back directly or into the star diagonal. To install an eyepiece: Figure 2-9 1. Loosen the thumbscrew on the star diagonal so that it does not obstruct the inner diameter of the eyepiece end of the diagonal. 2. Slide the chrome portion of the eyepiece into the star diagonal. 3.
Celestar Manual MOVING THE TELESCOPE IN R.A. AND DEC Pointing the telescope is done by moving the telescope in right ascension, or R.A. for short, and declination, or DEC for short (see Figure 2-11). Right ascension corresponds to east/west movement while declination corresponds to north/south movement. To make considerable directional changes: 1. Loosen the R.A. and DEC clamps on the mount. 2. Move the telescope until pointing in the desired direction. 3. Lock the R.A.
Celestar Manual the storage position. Here is how to install the R.A. encoder (please refer to Figure 2-12 and Figure 2-13 for all installation procedures): 1. Swing the telescope through the fork tines so that it is pointing straight up. 2. Slide the R.A. encoder shaft through the hole in the R.A. encoder bracket (i.e., the long, flat bracket). 3. Place the lock washer and nut over the encoder shaft and tighten fully. This will hold the encoder to the bracket. 4. Slide the R.A.
Celestar Manual R.A. Encoder 8-32 Phillips Pan Head Encoder Bracket Encoder Lock Nut Knurled R.A. Coupling Screw 6-32 Socket Set Screw Washer Spacer Figure 2-13 The installation of the R.A. encoder of the Advanced Astro Master is now complete. Keep in mind that the R.A. encoder must be removed when returning the telescope to the storage position. Now connect the blue connector on the cable to the five pins on the R.A.
Celestar Manual ADVANCED ASTRO MASTER SETUP (For Celestar 8 Computerized and Celestar Deluxe 8 Computerized Only) (See the Advanced Astro Master manual for complete directions) Once the Advanced Astro Master (AAM) is attached to the telescope, there are a few steps that need to be taken to make sure the AAM is set up for the Celestar 8. Although the AAM should already be set up for the Celestar 8, it is good practice to check and to familiarize yourself with the navigation process of the AAM.
Celestar Manual TRANSPORTING YOUR CELESTAR/CELESTAR DELUXE 8 You may leave your Celestar/Celestar Deluxe 8 fully set up in the house and carry it outside for a casual observing session. However, since the telescope is large and somewhat heavy on the tripod, you may want to remove the telescope and drive from the Wedgpod or tripod/wedge when moving it. To do so: 1. Remove the two lower bolts that hold the drive base to the tilt plate of the wedge or Wedgpod. 2.
Celestar Manual TELESCOPE BASICS Once your telescope is fully assembled, you are ready for your first look. This section deals with some of the basics of telescope operation. IMAGE ORIENTATION The image orientation changes depending on how the eyepiece is inserted into the telescope. When using the star diagonal, the image is right-side-up, but reversed from left-to-right (i.e., reverted). If inserting the eyepiece directly into the visual back (i.e.
Celestar Manual FOCUSING The Celestar 8 focusing mechanism controls the primary mirror which is mounted on a ring that slides back and forth on the primary baffle tube. The focusing knob, which moves the primary mirror, is on the rear cell of the telescope just right of the star diagonal and eyepiece. Turn the focusing knob until the image is sharp. If the knob will not turn, it has reached the end of its travel on the focusing mechanism. Turn the knob in the opposite direction until the image is sharp.
Celestar Manual YOUR FIRST LOOK With the telescope fully assembled and all the accessories attached, you are ready for your first look. Your first look should be done in the daytime when it is easier to locate the locking clamps and slow motion knobs. This will help to familiarize you with your Celestar 8, thus making it easier to use at night. Daytime Observing As mentioned in the introduction, your Celestron Celestar telescope works well as a terrestrial spotting scope.
Celestar Manual 3. Adjust the wedge in altitude until the latitude indicator points to the latitude of the site from which you are observing. 4. Insert a low power eyepiece (i.e., one with a long focal length 25mm) into the telescope to give you the widest field possible. 5. Turn the clock drive on. 6. Loosen the right ascension and declination clamps and point the telescope at the desired target. The Moon or one of the brighter planets is an ideal first target. 7.
Celestar Manual DETERMINING FIELD OF VIEW Determining the field of view is important if you want to get an idea of the angular size of the object you are observing. To calculate the actual field of view, divide the apparent field of the eyepiece (supplied by the eyepiece manufacturer) by the magnification.
Celestar Manual GENERAL PHOTOGRAPHY HINTS Your Celestar telescope can be used for both terrestrial and astronomical photography. Your Celestar telescope has a fixed aperture and, as a result, a fixed f/ratio. To properly expose your subjects photographically you need to set your shutter speed accordingly. Most 35mm single lens reflex (SLR) cameras offer through-the-lens metering which lets you know if your picture is under or overexposed.
Celestar Manual ASTRONOMY BASICS Up to this point, this manual covered the assembly and basic operation of your Celestron telescope. However, to use your telescope effectively, you need to know a little about the night sky. This section deals with observational astronomy in general and includes information on the night sky and polar alignment.
Celestar Manual MOTION OF THE STARS The daily motion of the Sun across the sky is familiar to even the most casual observer. This daily trek is not the Sun moving as early astronomers thought, but the result of the Earth's rotation. The Earth's rotation also causes the stars to do the same, scribing out a large circle as the Earth completes one rotation. The size of the circular path a star follows depends on where it is in the sky.
Celestar Manual POLAR ALIGNMENT In order for the telescope to track the stars, you must meet two criteria. First, you need a drive motor that moves at the same rate as the stars. The Celestron telescope comes standard with a built-in drive motor designed specifically for this purpose. The second thing you need is to set the telescope's axis of rotation so that it tracks in the right direction.
Celestar Manual Finding the Pole In each hemisphere, there is a point in the sky around which all the other stars appear to rotate. These points are called the celestial poles and are named for the hemisphere in which they reside. For example, in the northern hemisphere all stars move around the north celestial pole. When the telescope's polar axis is pointed at the celestial pole, it is parallel to the Earth's rotational axis.
Celestar Manual Latitude Scale Polar Alignment Method The easiest way to polar align a telescope is with a latitude scale. Unlike other methods that require you to find the celestial pole by identifying certain stars near it, this method works off of a known constant, latitude, to determine how high the polar axis should be pointed. The latitude range for the Celestar telescope is 0° to 90°.
Celestar Manual 2. Loosen the DEC clamp and move the telescope so that the tube is parallel to the polar axis. When this is done, the declination setting circle will indicate +90°. If the declination setting circle is not aligned, move the telescope so that the tube is parallel to the polar axis (see figure 4-6). 3. Adjust the mount in altitude and/or azimuth until Polaris is in the field of view of the finder. 4.
Celestar Manual To perform the declination drift method you need to choose two bright stars. One should be near the eastern horizon and one due south near the meridian. Both stars should be near the celestial equator (i.e., 0° declination). You will monitor the drift of each star one at a time and in declination only. While monitoring a star on the meridian, any misalignment in the east-west direction is revealed.
Celestar Manual 4. Start the clock drive so that the mount tracks the star. 5. Look up the coordinates of the star. You can consult a star catalog or use the list at the end of this manual. 6. Rotate the R.A. circle until the proper coordinates line up with the R.A. indicator. The R.A. setting circle should rotate freely. The R.A. setting circle has a marker every five minutes with each hour labeled The R.A. setting circle is now aligned and ready to use. The R.A. setting circle is clutched to the R.
Celestar Manual USING THE CELESTAR DRIVE The Celestar 8 comes with a built-in single motor spur gear clock drive to track objects as they move across the sky. The Celestar 8 is DC powered and operated by an internal 9-volt battery that is included with the telescope. In addition, the Celestar 8 has built-in electronics that when used in conjunction with the optional hand controller allow you to do long exposure deep-sky astrophotography. Following is a brief description of each function.
Celestar Manual Outlets On the drive base cover there are three outlets, two miniature jacks and one modular telephone jack. Starting from the left, the first is labeled “Hand.” This is the outlet that the optional hand controller plugs into. To plug the hand controller into the drive base: 1. Hold the end of the cable with the modular telephone jack over the outlet in the base. 2. Orient the jack so that the plastic tab is down. 3. Slide the jack into the outlet until it clicks.
Celestar Manual telescope south. If you are NOT using the optional DEC motor then all corrections to the declination axis must be made manually (i.e., by turning the DEC slow motion knob). If the drive does not respond when the correction buttons have been pressed, check to make sure that the hand controller cable is plugged into the drive base correctly. NORTHERN/SOUTHERN HEMISPHERE OPERATION When using your Celestar 8 in the southern hemisphere, there is a need to reverse the direction of the R. A.
Celestar Manual USING THE CELESTAR DELUXE DRIVE The Celestar Deluxe drive system uses a combination of a precision ground worm and a 5.5” diameter, 266 tooth anodized aluminum helical gear for superior tracking accuracy. The drive system employs stepper motors on each axis for quick response to guiding corrections and extremely accurate tracking rates.
Celestar Manual 4. The LED above the ON/OFF switch will turn on and the tracking motor will start tracking. TRACKING RATE SELECTION Figure 6-2 Refraction caused by the Earth’s atmosphere makes celestial objects within 45° of the horizon appear higher in the sky then they actual are. This refraction also affects the rate at which stars rise and set. King rate takes this refraction into account. The drive has four basic rates: sidereal, solar, lunar and King.
Celestar Manual 4. Take a few minutes to practice guiding. This will help you familiarize yourself with the periodic error of the drive and the operation of the hand control box. 5. Press the “PEC” button once to activate the record (REC) mode. You will have 5 seconds before the system starts to record. During this time the LED will blink once a second. When the duration of the illumination changes to a half second, it indicates the record mode is active.
Celestar Manual Note: If the DEC and/or focus motors are used , the maximum operating time of the drive is reduced when using the internal 9-volt battery. THE HAND CONTROLLER The hand controller is essential for long exposure deep sky photography. For normal observing it serves as a convenient aid for centering objects especially at high power. On the hand controller there are four buttons used to make guiding corrections in right ascension and declination during astrophotography.
Celestar Manual Clutch Adjustment Knob Dec Motor Figure 6-3 REPLACING THE BATTERY Once the batteries have been drained, they should be replaced. Replacing the alkaline batteries requires removal of the drive base cover. To do this: 1. Remove the four Phillips head screws that hold the drive base cover to the drive base. 2. Remove the cover plate by first lifting it up and then sliding it out (see Figure 6-4 and Figure 6-5). The internal components of the drive will be visible.
Celestar Manual 4. Remove the terminals from the batteries. 5. Install the new batteries by attaching them to the terminals and clip them into the battery holders. 6. Replace the drive base cover and secure with the four 4-40 screws. To obtain the longest possible run time, use alkaline batteries. Alkaline batteries will power the drive for up to 8 hours of continuous use. (Nickel cadium or standard 9-volt batteries are NOT recommended).
Celestar Manual CELESTIAL OBSERVING With your telescope set up, you are ready to use it for observing. This section covers visual observing for both solar system and deep sky objects. OBSERVING THE MOON In the night sky, the Moon is a prime target for your first look because it is extremely bright and easy to find. Often, it is tempting to look at the Moon when it is full. At this time, the face we see is fully illuminated and its light can be overpowering.
Celestar Manual OBSERVING THE SUN Although overlooked by many amateur astronomers, solar observation is both rewarding and fun. However, because the Sun is so bright, special precautions must be taken when observing our star so as not to damage your eyes or your telescope. Never project an image of the Sun through the telescope. Because of the folded optical design, tremendous heat build-up will result inside the optical tube. This can damage the telescope and/or any accessories attached to the telescope.
Celestar Manual 6. Move the telescope in declination until the indicator points at the correct declination coordinate. 7. Move the telescope in R.A. until the indicator points to the correct coordinate (do NOT move the R.A. circle). 8. Look through the finder to see if you have located the object. 9. Center the object in the finder. 10. Look in the main optics using a low power eyepiece; the object should be there. The telescope will track in R.A. as long as the clock drive is operating. 11.
Celestar Manual Figure 7-1 Star hopping to the Andromeda Galaxy (M31) is a snap since all the stars needed to do so are visible to the naked eye. Note that the scale for this star chart is different from the one on the following page which shows the constellation Lyra. Star hopping may take some getting used to since you can see more stars through the finder than you can see with the naked eye. And, some objects are not visible in the finder. One such object is M57, the famed Ring Nebula.
Celestar Manual Figure 7-2 SEEING CONDITIONS Viewing conditions affect what you can see through your telescope during an observing session. Conditions include transparency, sky illumination, and seeing. Understanding viewing conditions and the effect they have on observing will help you get the most out of your telescope. Transparency Transparency is the clarity of the atmosphere which is affected by clouds, moisture, and other airborne particles.
Celestar Manual Seeing conditions refers to the stability of the atmosphere and directly effects the amount of fine detail seen in extended objects. The air in our atmosphere acts as a lens which bends and distorts incoming light rays. The amount of bending depends on air density. Varying temperature layers have different densities and, therefore, bend light differently. Light rays from the same object arrive slightly displaced creating an imperfect or smeared image.
Celestar Manual 52 Celestial Photography
Celestar Manual CELESTIAL PHOTOGRAPHY After looking at the night sky for a while you may want to try photographing it. Several forms of celestial photography are possible with your Celestar telescope. The most common forms of celestial photography, in order of difficulty are; short exposure prime focus, piggyback, eyepiece projection, and long exposure deep sky. Each of these is discussed in moderate detail with enough information to get you started.
Celestar Manual With your camera attached to the telescope, you are ready for prime focus photography. Start with an easy object like the Moon. Here's how to do it: 1. Load your camera with film that has a moderate-to-fast speed (i.e., ISO rating). Faster films are more desirable when the Moon is a crescent. When the Moon is near full, and at its brightest, slower films are more desirable.
Celestar Manual guiding with a high power telescope, the margin for error is very large. Small mistakes made while guiding the telescope will not show up on film. To attach the camera to the telescope, use the piggyback mount (#93598). This can be purchased as an optional accessory. As with any form of deep-sky photography, it should be done from a dark sky observing site. Light pollution around major urban areas washes out the faint light of deep-sky objects. 1.
Celestar Manual As you perfect your technique, try specialized films, that is films that are designed or specially treated for celestial photography. Here are some popular choices: • • • • Ektar 125 (color print) Fujichrome 100D (color slide) Tech Pan, gas hypered (black and white print) T-Max 400 (black and white print) As with all forms of photography, keep accurate records of your work.
Celestar Manual 4. Release the shutter using a cable release. 5. Wait for the vibration caused by releasing the shutter to diminish. Also, wait for a moment of good seeing. 6. Remove the black card from in front of the telescope for the duration of the exposure (see accompanying table). 7. Replace the black card over the front of the telescope. 8. Close the camera's shutter. Advance the film and you are ready for your next exposure.
Celestar Manual There are several techniques for this type of photography, and the one chosen will determine the standard accessories needed. If, for example, you use a separate guidescope, the camera attaches to the telescope with a T-Adapter (#93633-A) and a T-Ring for your specific camera. However, the best method for long exposure deep sky astrophotography is with an off-axis guider. This device allows you to photograph and guide through the telescope simultaneously.
Celestar Manual As you perfect your technique, try specialized films, that is films that are designed or specially treated for celestial photography. Here are some popular choices: • • • • Ektar 125 (color print) Fujichrome 100D (color slide) Tech Pan, gas hypered (black and white print) T-Max 400 (black and white print) There is no exposure determination table to help you get started.
Celestar Manual CCD IMAGING Fastar Lens Assembly Option – Using your Celestar Deluxe telescope at f/1.95 with optional PixCel CCD Camera Your Celestar Deluxe telescope is equipped with a removable secondary mirror that allows you to convert your f/10 telescope into an f/1.95 imaging system capable of exposure times 25 times shorter than those needed with a f/10 system! Used with Celestron's PixCel CCD System, objects will be easily found due to the ultra-wide 2/3• by 1/2• field of view provided.
Celestar Manual DESCRIPTION OF F-NUMBERS The F/# stands for the ratio between the focal length and the diameter of the light gathering element. A standard C8 has a focal length of 80 inches and a diameter of 8 inches. This makes the system an f/10, (focal length divided by diameter). When the secondary is removed and the CCD is placed at the Fastar position, the system becomes f/1.95, this is unique to Celestron telescopes (see figures below).
Celestar Manual improved upon dramatically if several 30-60 second exposures are added together using the Track and Accumulate™ feature. Figure 8-4 M27 – The Dumbbell Nebula 4 exposures of 30 seconds each! Figure 8-5 M51 – The Whirlpool Nebula 9 exposures of 60 second each. When imaging some objects like planetary nebula (for example M57, the Ring Nebula) and small galaxies (M104, the Sombrero Galaxy), larger image scale is needed to resolve finer detail. These objects are better shot at f/6.
Celestar Manual Figure 8-6 - Accessory Configurations for Fastar Compatible Telescopes 1 Optical Tube Assembly 12 Pulstar Illuminator 2 Secondary Mirror 13 Illuminator (Microguide Eyepiece only) 3 Secondary Mirror Retaining Ring 14 Reducer/Corrector f/6.
Celestar Manual TELESCOPE MAINTENANCE While your Celestar telescope requires little maintenance, there are a few things to remember that will ensure your telescope performs optimally. CARE AND CLEANING OF THE OPTICS Occasionally, dust and/or moisture may build up on the corrector plate of your Celestar telescope. Special care should be taken when cleaning any instrument so as not to damage the optics.
Celestar Manual Figure 9-1 A collimated pattern (left) of a slightly out-of-focus star shows concentric rings. An example of an out of collimation system (right) is shown by nonsymmetric rings that flare out to one side. To check the collimation of your telescope you will need a light source. A bright star near the zenith is ideal since there is a minimal amount of atmospheric distortion. Turn your telescope drive on so that you won't have to manually track the star.
OPTIONAL ACCESSORIES The following is a partial list of optional accessories that can be used with your Celestar telescope. Accessory Name - Part Number - Description Compatible with Celestar Celestar Deluxe AC Adapter - 110V - 60Hz (#18772) - The AC Adapter allows you to run your Celestar 8 and Celestar 8 Computerized off AC rather than the standard DC battery. X X Accessory Case (#93500) - This rugged ABS plastic case is designed for carrying a few accessories.
Accessory Name - Part Number - Description Compatible with Celestar Celestar Deluxe C-5/C-8 Case (302070) - This case is perfect for storing the Celestar telescope with the finderscope attached. It is constructed of space age resin, making it waterproof, unbreakable, airtight and extremely durable. The case is lined with die cut foam for custom fitting. (31.5” x 21.75” x 11.
Accessory Name - Part Number - Description Compatible with Celestar Celestar Deluxe produces images through your Celestar that match what you see with the unaided eye. This accessory uses an Amici prism arrangement that, corrects the image. The model #94112-A allows you to look into the telescope at a 45° angle, a desirable arrangement for terrestrial viewing. If you desire to view at a 90º angle, then model #94108 is available.
Accessory Name - Part Number - Description Compatible with Celestar Celestar Deluxe In addition to the previously mentioned, there is also a deluxe compact zoom ocular (#93306) that has a variable focal length of 6.5 to 18mm. This provides 111 to 307 power on the C8 when used at prime focus. Finders - Finders are used to help you locate objects in the main telescope. The larger the finder, the more you will see, making it easier to locate objects.
Accessory Name - Part Number - Description Compatible with Celestar Celestar Deluxe and low pressure sodium vapor lights. In addition, they also block unwanted natural light (sky glow) caused by neutral oxygen emission in our atmosphere. Celestron offers a model for 1-l/4" eyepieces (#94126A) and a model that attaches to the rear cell ahead of the star diagonal and visual back (#94127A). Micro Guide Eyepiece (#94171) - This multipurpose illuminated 12.
Accessory Name - Part Number - Description Compatible with Celestar Celestar Deluxe orientation making the acquisition of a guide star quite easy. Second, the prism angle is tunable allowing you to look at guide stars on-axis. Reducer/Corrector (#94175) - This lens reduces the focal length of the telescope by 37%, making your C8 a l280mm f/6.3 instrument. In addition, this unique lens also corrects inherent aberrations to produce crisp images all the way across the field.
Accessory Name - Part Number - Description Compatible with Celestar Celestar Deluxe T-C Adapter (#93636) - This adapter allows you to couple a video or movie camera to a telescope. The camera must have a removable lens with a standard "C" thread. The T-C adapter threads into the camera and then onto the T-Adapter. X X T-Ring - The T-Ring couples your camera body to the T-Adapter, Radial Guider Body, or Tele-Extender. This accessory is mandatory if you want to do astrophotography through the telescope.
THE MESSIER CATALOG The Messier Catalog, compiled by Charles Messier, was the first extensive listing of star clusters and nebulae. Messier’s primary observational purpose was to discover comets. He compiled this list so that others searching for comets would not be confused by these objects. His list still remains popular today because all of these objects are easily visible in amateur telescopes. M# NGC# Const. R.A.
M# NGC# Const. R.A. DEC Mag Type Proper Name M31 M32 M33 M34 M35 NGC 224 NGC 221 NGC 598 NGC 1039 NGC 2168 And And Tri Per Gem 0 42.7 0 42.7 1 33.8 2 42.0 6 08.8 41 16 40 52 30 39 42 47 24 20 3.4 8.2 5.7 5.2 5.1 Sp. Gx. El. Gx. Sp. Gx. Op. Cl. Op. Cl. Andromeda Galaxy M36 M37 M38 M39 M40 NGC 1960 NGC 2099 NGC 1912 NGC 7092 Aur Aur Aur Cyg UMa 5 36.3 5 52.0 5 28.7 21 32.3 12 22.2 34 08 32 33 35 50 48 26 58 05 6.0 5.6 6.4 4.6 8.0 Op. Cl. Op. Cl. Op. Cl. Op. Cl.
M# NGC# Const. R.A. DEC Mag Type M71 M72 M73 M74 M75 NGC 6838 NGC 6981 NGC 6994 NGC 628 NGC 6864 Sge Aqr Aqr Psc Sgr 19 53.7 20 53.5 20 58.0 1 36.7 20 06.1 18 47 -12 32 -12 38 15 47 -21 55 8.3 9.4 9.2 8.6 Gl. Cl. Gl. Cl. ast S Gl Cl. M76 M77 M78 M79 M80 NGC 650-1 NGC 1068 NGC 2068 NGC 1904 NGC 6093 Per Cet Ori Lep Sco 1 42.2 2 42.7 5 46.7 5 24.2 16 17.0 51 34 0 01 0 03 -24 33 -22 59 11.5 8.8 8.0 8.0 7.2 P. Neb. Sp. Gx. D. Neb. Gl. Cl. Gl. Cl.
Object Abbreviations: • • • • • • • Sp. Gx. El. Gx. Ir. Gx. Op. Cl. Gl. Cl. D. Neb. P. Neb. Spiral Galaxy Elliptical Galaxy Irregular Galaxy Open Cluster Globular Cluster Diffuse Nebula Planetary Nebula NOTE: All coordinates for the objects in the Messier catalog are listed in epoch 2000.00.
LIST OF BRIGHT STARS The following is a list of bright stars that can be used to align the R.A. setting circle. All coordinates are in epoch 2000.0. Star Name HMS Epoch 2000.0 R.A. DEC HMS °‘ “ Magnitude Sirius Canopus Arcturus Rigel Kent. Vega CMa Car Boo Cen Lyr 06 45 09 06 23 57 14 1540 14 39 37 18 3656 -16 42 58 -52 41 44 +19 1057 -60 50 02 +38 4701 -1.47 -0.72 -0.72 +0.01 +0.
TECHNICAL SPECIFICATIONS Optical Tube Design Aperture: Focal Length: F/ratio: Highest Useful Magnification: Lowest Useful Magnification: Resolution Photographic Resolution: Light Gathering Power: Back Focus Near Focus with Eyepiece: Near Focus with Camera: Optical Tube Length: Optical Tube Diameter R.A. Setting Circle Diameter Northern Hemisphere: R.A. Setting Circle Diameter Southern Hemisphere: DEC. Setting Circle Diameter: DEC.
FURTHER READING The following is a list of astronomy books that will further enhance your understanding of the night sky. The books are broken down by classification for easy reference. Astronomy Texts Astronomy Now................................................................................Pasachoff & Kutner Cambridge Atlas Of Astronomy.......................................................Audolsze & Israel McGraw-Hill Encyclopedia Of Astronomy .....................................
CELESTRON LIMITED WARRANTY CELESTRON PRODUCTS Celestron International (CI) warrants that each Celestron telescope shall be free from defects in materials and workmanship for one year. CI repair or replace such product or part thereof which, on inspection by CI is found to be defective in materials or workmanship. As a condition to the obligation of CI to repair or replace such product, the product must be returned to CI together with proof-of-purchase satisfactory to CI.
Some states do not allow the exclusion or limitation of incidental or consequential damages or limitation on how long an implied warranty lasts, so the above limitations and exclusions may not apply to you. This warranty gives you specific legal rights, and you may also have other rights which vary from state to state. CI reserves the right to modify or discontinue, without prior notice to you, any model or style optical instrument.
