Celestron C8-S, C5-S, C9.25-S instruction manual Eyepiece Projection, Full

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•T-Max 400

•Any 100 to 400 ISO color slide film

•Fuji Super HG 400

•Ektar 25 or 100

2.Center the Moon in the field of your telescope.

3.Focus the telescope by turning the focus knob until the image is sharp.

4.Set the shutter speed to the appropriate setting (see table below).

5.Trip the shutter using a cable release.

6.Advance the film and repeat the process.

Lunar Phase

ISO 50

ISO 100

ISO 200

ISO 400

Crescent

1/2

1/4

1/8

1/15

Quarter

1/15

1/30

1/60

1/125

Full

1/30

1/60

1/125

1/250

Table 7-1

Above is a listing of recommended exposure times when photographing the Moon at the

prime focus of your telescope.

The exposure times listed in table 7-1 should be used as a starting point. Always make exposures that are longer and shorter than the recommended time. Also, take a few photos at each shutter speed. This will ensure that you will get a good photo.

•If using black and white film, try a yellow filter to reduce the light intensity and to increase contrast.

•Keep accurate records of your exposures. This information is useful if you want to repeat your results or if you want to submit some of your photos to various astronomy magazines for possible publication!

•This technique is also used for photographing the Sun with the proper solar filter.

Eyepiece Projection

This form of celestial photography is designed for objects with small angular sizes, primarily the Moon and planets. Planets, although physically quite large, appear small in angular size because of their great distances. Moderate to high magnification is, therefore, required to make the image large enough to see any detail. Unfortunately, the camera/telescope combination alone does not provide enough magnification to produce a usable image size on film. In order to get the image large enough, you must attach your camera to the telescope with the eyepiece in place. To do so, you need two additional accessories; a deluxe tele-extender (#93643), which attaches to the visual back, and a T-ring for your particular camera make (i.e., Minolta, Nikon, Pentax, etc.).

Because of the high magnifications during eyepiece projection, the field of view is quite small which makes it difficult to find and center objects. To make the job a little easier, align the finder as accurately as possible. This allows you to get the object in the telescope's field based on the finder's view alone.

Another problem introduced by the high magnification is vibration. Simply tripping the shutter  even with a cable release  produces enough vibration to smear the image. To get around this, use the camera's self-timer if the exposure time is less than one second  a common occurrence when photographing the Moon. For exposures over one second, use the "hat trick." This technique incorporates a hand-held black card placed over the aperture of the telescope to

Figure 7-1 - Accessories for

Projection Photography

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Contents Advanced Series Advanced Series GT Introduction Assembly Telescope Maintenance Page Advanced Series Autoguider Port Advanced C8-SGT ShownC9.25-S Setting up the TripodInstalling the Counterweight Bar Attaching the Equatorial MountAttaching the Center Leg Brace Attaching the Hand Control Holder Advanced GT Models Only Installing the CounterweightAttaching the Visual Back Attaching the Optical Tube to the MountEyepiece Installing the Star DiagonalInstalling the Eyepiece Installing the FinderscopeRemoving the Lens Cap Moving the Telescope ManuallyRear Cell Balancing The Mount in DEC Balancing The Mount in R.AAdjusting the Mount Adjusting the Mount in AltitudeAdjusting the Mount in Azimuth Attaching the Declination Cables For GT Models Only Powering the TelescopeAdvanced GT Hand Control Hand Control Operation Startup Procedure Alignment ProceduresAuto Three-Star Align Auto AlignQuick-Align Last AlignmentRe-Alignment Finding Planets Object CatalogSelecting an Object Slewing to an ObjectRate Button Tour ModeConstellation Tour Direction ButtonsSetup Procedures Identify Precise GoTo Observing Tip Helpful Hint Utility Features Helpful Hint Advanced GT Celestial Coordinate System Motion of the Stars Pointing at Polaris Latitude ScalesFinding the North Celestial Pole Declination Drift Method of Polar Alignment Observing the Sun Observing the MoonLunar Observing Hints Observing the PlanetsTransparency Solar Observing HintsObserving Deep Sky Objects Seeing ConditionsPage Short Exposure Prime Focus Photography Full Eyepiece ProjectionPlanet ISO Moon Mercury Venus Mars Jupiter Saturn Long Exposure Prime Focus PhotographyPage CCD Imaging Terrestrial PhotographyMetering Reducing VibrationAuto Guiding Collimation Care and Cleaning of the OpticsCollimated telescope Should appear Symmetrical with Page Page Page Appendix a Technical Specifications Appendix B Glossary of Terms Page Eclipsing or obscuring the brightness of the star Appendix C Longitudes Latitudes Georgia Minnesota Rhode Island Canada Communication Protocol Appendix D RS-232 ConnectionReset The Position Of Azm Or Alt Additional RS232 CommandsAppendix E Maps of Time Zones Page Page Page Page Page Page Page Celestron TWO Year Warranty
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C9.25-S, C5-S, C8-S specifications

Celestron, a leader in the field of amateur and professional astronomy, offers a range of telescopes ideal for both novices and experienced stargazers. Among their most celebrated models are the C8-S, C5-S, and C9.25-S, each designed with unique features and technologies that enhance the observational experience.

The Celestron C8-S is an iconic telescope known for its 8-inch aperture. This Schmidt-Cassegrain design combines a compact form factor with a powerful light-gathering capability, making it perfect for deep-sky observing. Its optical tube has a focal length of 2032mm, providing an excellent balance of wide field viewing and high magnification. The C8-S features Celestron's StarBright XLT optical coating, enhancing light transmission and contrast, ensuring that even faint objects are visible. With compatibility for various accessories and a sturdy mount, the C8-S stands as a versatile option for different observing styles.

Moving to the C5-S, this model boasts a 5-inch aperture while maintains a compact and portable design. It is particularly popular among travelers and casual astronomers who value convenience without compromising on quality. The C5-S also employs the Schmidt-Cassegrain design, providing sharp images and improved color correction. With its shorter focal length of 1250mm, the C5-S excels in both planetary and deep-sky observation. The telescope's lightweight build makes it easy to transport, while the integrated optical systems ensure a clear view of celestial objects.

The C9.25-S represents a step up in performance, featuring a 9.25-inch aperture that captures more light than its smaller counterparts. This telescope offers a versatile focal length of 2350mm, allowing for impressive high-power planetary views, as well as detailed observations of deep-sky objects. The C9.25-S utilizes a unique StarBright XLT coating and features advanced optics that minimize optical distortion, resulting in sharp, high-contrast images. It is equipped with a sturdy mount that ensures stability during extended observation sessions.

All three models are compatible with Celestron's advanced computer-driven mount systems, allowing for effortless tracking and alignment. With built-in features such as GoTo technology, users can easily locate thousands of celestial objects with the touch of a button. This combination of advanced optics, portability, and user-friendly technology makes the Celestron C8-S, C5-S, and C9.25-S excellent choices for anyone looking to explore the cosmos more deeply. Whether for casual stargazing or serious astronomical study, these telescopes deliver exceptional performance to meet a variety of needs.
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