Celestron C5 SC XLT telescope (52291)

Celestron C5 Schmidt-Cassegrain XLT Optical Tube (52291)

The Celestron C5 Schmidt-Cassegrain XLT is a compact, lightweight optical tube designed for observers who want excellent performance in an exceptionally portable package. With a 127 mm (5-inch) aperture, a tube length of only 330 mm, and a weight of just 2.7 kg, the C5 is one of the most travel-friendly telescopes in its class.

Its Schmidt-Cassegrain optical design combines a spherical primary mirror, an aspheric Schmidt corrector plate, and a secondary mirror to produce sharp, high-contrast images while maintaining a remarkably compact form factor.

Equipped with Celestron's premium StarBright XLT optical coatings, the telescope delivers up to 16% greater light transmission compared to conventional coatings, resulting in brighter images and improved contrast.

The C5 is equally suited for astronomy, wildlife observation, and long-range terrestrial photography.

Key features

• 127 mm (5-inch) Schmidt-Cassegrain optical system.

• 1270 mm focal length.

• f/10 focal ratio.

• Compact 330 mm optical tube.

• Lightweight 2.7 kg design.

• Premium StarBright XLT optical coatings.

• Compatible with optional f/6.3 focal reducer.

• Vixen-style dovetail rail.

• Standard 1/4-inch tripod thread.

• Excellent for astronomy, terrestrial observation, and telephoto photography.

Schmidt-Cassegrain optical system

The telescope employs the classic Schmidt-Cassegrain optical configuration consisting of:

• Schmidt corrector plate.

• Primary mirror.

• Secondary mirror.

• Rear focusing mechanism.

Compared with Maksutov-Cassegrain telescopes of similar aperture, Schmidt-Cassegrain systems typically offer a shorter focal length and greater versatility.

When paired with an optional focal reducer, the focal ratio can be reduced to approximately f/6.3, providing a wider field of view and shorter photographic exposure times.

The internal focusing mechanism moves the primary mirror along the optical axis using a rear-mounted focusing knob, allowing smooth focus adjustment over a wide range of accessories.

Premium StarBright XLT coatings

All optical surfaces are treated with Celestron's StarBright XLT multi-layer coatings.

These premium coatings provide:

• Up to 16% higher light transmission than standard coatings.

• Improved image brightness.

• Higher contrast.

• Better visibility of faint celestial objects.

Astronomical performance

Despite its compact dimensions, the C5 is capable of detailed observations of many celestial objects.

It provides impressive views of:

• The Moon.

• Jupiter and its cloud belts.

• Saturn and its ring system.

• Mars during favorable oppositions.

• Bright open star clusters.

• Globular clusters.

• Planetary nebulae.

• Bright galaxies.

Its relatively short minimum focusing distance also makes it suitable for observing nearby terrestrial subjects.

Terrestrial observation and photography

The Celestron C5 is widely used as a compact telephoto optical system for wildlife and nature photography.

Using an appropriate T-adapter and T-ring, DSLR or mirrorless cameras can be attached easily, transforming the telescope into a powerful long-focus photographic lens.

The included 45° erect-image prism diagonal provides correctly oriented images for comfortable daytime observation.

Portable design

The optical tube features:

• Vixen-style dovetail mounting rail.

• Standard 1/4-inch tripod thread.

This allows the telescope to be mounted on astronomical mounts as well as many photographic tripods.

Its compact dimensions make it an excellent choice for travel, field observation, and portable astronomy.

Included accessories

• 45° erect-image prism diagonal.

• 25 mm eyepiece (approximately 50× magnification).

• 8×20 finder scope.

• 1.25-inch visual back.

• Protective waterproof foam carrying case.

Technical specifications

General

• Catalog number:

  • 52291.

• Product series:

  • Celestron XLT.

• Optical design:

  • Schmidt-Cassegrain.

• Mount:

  • Optical tube only (no mount included).

Optical specifications

• Aperture:

  • 127 mm.

• Focal length:

  • 1270 mm.

• Focal ratio:

  • f/10.

• Limiting stellar magnitude:

  • 13.1.

• Maximum useful magnification:

  • 254×.

• Rayleigh resolution:

  • 1.13 arcseconds.

• Dawes resolution:

  • 0.91 arcseconds.

• Light-gathering power:

  • 329×.

Optical tube

• Tube weight:

  • 2.7 kg.

• Tube length:

  • 330 mm.

• Tube diameter:

  • 152 mm.

Focuser

• Type:

  • SCT/MAK rear focusing system.

• Eyepiece connection:

  • 1.25 inches.

• Fine-focus reduction:

  • No.

Optical characteristics

• Central obstruction:

  • 37%.

• Optical coatings:

  • StarBright XLT.

Mounting

• Dovetail standard:

  • Vixen.

• Additional mounting thread:

  • 1/4-inch photographic thread.

Warranty

• Manufacturer's warranty:

  • 36 months.