Celestron 93507 manual Long Exposure Prime Focus Photography

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2.Turn the focus knob until the image is as sharp as possible.

3.Place the black card over the front of the telescope.

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. Don't forget to take photos of varying duration and keep accurate records of what you have done. Record the date, telescope, exposure duration, eyepiece, f/ratio, film, and some comments on the seeing conditions.

The following table lists exposures for eyepiece projection with a 10mm eyepiece. All exposure times are listed in seconds or fractions of a second.

Planet

ISO 50

ISO 100

ISO 200

ISO 400

Moon

4

2

1

1/2

Mercury

16

8

4

2

Venus

1/2

1/4

1/8

1/15

Mars

16

8

4

2

Jupiter

8

4

2

1

Saturn

16

8

4

2

Table 8-2

Recommended exposure time for photographing planets.

The exposure times listed here 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 get a good photo. It is not uncommon to go through an entire roll of 36 exposures and have only one good shot.

NOTE: Don't expect to record more detail than you can see visually in the eyepiece at the time you are photographing.

Once you have mastered the technique, experiment with different films, different focal length eyepieces, and even different filters.

Long Exposure Prime Focus Photography

This is the last form of celestial photography to be attempted after others have been mastered. It is intended primarily for deep sky objects, that is objects outside our solar system which includes star clusters, nebulae, and galaxies. While it may seem that high magnification is required for these objects, just the opposite is true. Most of these objects cover large angular areas and fit nicely into the prime focus field of your telescope. The brightness of these objects, however, requires long exposure times and, as a result, are rather difficult.

There are several techniques for this type of photography, and the one chosen will determine the standard accessories needed. 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. Celestron offers a very special and advanced off- axis guider, called the Radial Guider (#94176). In addition, you will need a T-Ring to attach your camera to the Radial Guider.

Other equipment needs include a guiding eyepiece. Unlike other forms of astrophotography which allows for fairly loose guiding, prime focus requires meticulous guiding for long periods. To accomplish this you need a guiding ocular with an illuminated reticle to monitor your guide star. For this purpose, Celestron offers the Micro Guide Eyepiece (#94171) Here is a brief summary of the technique.

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Contents Page Introduction Quick Setup Assembly Telescope Maintenance Appendix E Time Zone MAP SKY Maps Observational Data Sheet Page Center Leg Brace Tension KnobLeg Finderscope Alignment Star Auxiliary Port Control PanelAssembling the NexStar Setting Up The TripodAttaching the NexStar to the Tripod Adjusting the Tripod Height3a Attaching the Hand Control for NexStar 8 GPS Attaching the Hand ControlEyepiece Adjusting the ClutchesStar Diagonal Finderscope Finderscope InstallationAligning the Finderscope Powering the NexStarNexStar Hand Control Hand Control Operation Alignment ProceduresGPS Alignment Few Words on GPSHint Auto-AlignHelpful Helpful Hint Two Star AlignmentQuick-Align NexStar Re-Alignment EQ North / EQ South AlignmentFinding Planets Object CatalogSelecting an Object Slewing to an ObjectRate Button Tour ModeDirection Buttons Alt-Az Setup ProceduresEQ North EQ SouthScope Setup Features Menu Utility FeaturesHelpful Hint Menu Alignment List NexStar GPSImage Orientation Determining Field of View FocusingCalculating Magnification General Observing Hints Celestial sphere seen from the outside showing R.A. and DEC Celestial Coordinate SystemMotion of the Stars Wedge Align Polar Alignment with optional WedgeFinding the North Celestial Pole Definition Declination Drift Method of Polar AlignmentPage Observing the Planets Observing the MoonLunar Observing Hints Planetary Observing HintsObserving Deep Sky Objects Observing the SunSeeing Conditions TransparencySeeing Short Exposure Prime Focus Photography Full Lunar Phase ISO Crescent QuarterEyepiece Projection Planet ISO Moon Mercury Venus Mars Jupiter Saturn Long Exposure Prime Focus PhotographyUsing Periodic Error Correction Periodic Error Correction PECTerrestrial Photography Reducing Vibration CCD ImagingMetering Fastar Compatible Optical System With Reducer/Corrector Fastar F/2 ImagingAuto Guiding Pin out diagram for Autoguider portCollimation Care and Cleaning of the OpticsCollimated telescope Should appear Super Modified Achromatic SMA Eyepieces 1 ¼ Page Page Electronic Specifications Optical Specification NexStar 8 GPS NexStar 11 GPSMechanical Specifications Software SpecificationsAppendix B Glossary of Terms Page Page Appendix C Longitudes Latitudes Georgia Minnesota Rhode Island Canada Communication Protocol Description PC Command Ascii Hand Control ResponseSend Any Track Rate Through RS232 To The Hand Control Send a Slow-Goto Command Through RS232 To The Hand ControlReset The Position Of Azm Or Alt Appendix E Maps of Time Zones Page Page Page Page Page Page Page Observational Data Sheet Celestron TWO Year Warranty

93507 specifications

The Celestron 93507 is a powerful and versatile telescope designed for both amateur and seasoned astronomers. This model combines advanced technologies and practical features to deliver an enriching stargazing experience. One of the standout characteristics of the Celestron 93507 is its robust optical design. It features a 90mm aperture, allowing users to capture bright, detailed views of celestial objects, from the lunar surface to distant galaxies. The telescope employs a Maksutov-Cassegrain optical design, known for its compact form factor and high-quality images, free from chromatic aberration.

In terms of usability, the Celestron 93507 is designed with an easy setup in mind. It comes equipped with a solid mount that provides stability during observation. The mount also includes slow-motion controls, facilitating smooth panning across the night sky, allowing astronomers to track celestial objects effortlessly. This feature is particularly beneficial for viewing planets and other fast-moving astronomical phenomena.

Furthermore, the telescope comes with high-grade optics, including fully coated glass elements that enhance light transmission and ensure sharper images with higher contrast. It includes two eyepieces — a low-power 25mm and a high-power 10mm — that provide versatility in viewing options, whether you’re looking at wide expanses of the night sky or zooming in on close details of lunar craters.

Additionally, the Celestron 93507 is compatible with various Celestron accessories, including solar filters and advanced eyepieces, enabling users to expand their observational capabilities. The telescope's compact design makes it portable, perfect for amateur astronomers who enjoy taking their telescope for trips to dark-sky locations.

Another noteworthy feature of this telescope is its durability. Built to withstand the rigors of outdoor usage, the materials used in the Celestron 93507 are resistant to wear and tear, ensuring that users can enjoy stargazing for years.

Overall, the Celestron 93507 is a well-rounded instrument that combines advanced optical technology, user-friendly features, and portability, making it an excellent choice for anyone looking to explore the wonders of the universe. Whether you're interested in planetary observation, lunar details, or deep-sky wonders, this telescope offers the tools necessary to make your astronomical explorations rewarding.
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