9.25-inch Telescopes (235mm)

What is a 9.25-inch telescope?

A 9.25-inch telescope, known for its large aperture size, boasts a significant light-gathering ability and high resolution in observing celestial objects. The aperture of this telescope, approximately 25 inches in diameter, allows for a maximum magnification power of around 120x to 250x, with a theoretical limit of 463x, making it a powerful instrument for astronomical observations. The telescope’s gathering power is 100 times that of the human eye, enabling clearer and more detailed observations of faint celestial objects in space, thus enhancing astronomical research capabilities.

In terms of optical design, the 9.25-inch telescope typically features a Cassegrain or Maksutov-Cassegrain design, which allows for a long focal length in a compact body, enabling higher magnification capabilities and portability. The focal length of a 9.25-inch telescope can be calculated by multiplying the focal ratio by the aperture diameter, with the ideal focal ratio falling around f/10 to f/12. The focal length of a 9.25-inch Maksutov-Cassegrain telescope is approximately 635mm.

The telescope’s eyepieces play a crucial role in magnifying the image created by the objective lens or mirror, allowing for better observation of distant objects. The eyepieces can be interchanged to adjust the magnification and field of view, providing flexibility in observing various celestial phenomena. The typical field of view for a 9.25-inch telescope is around 6.5 meters in diameter, offering a wide perspective of the night sky.

The 9.25-inch telescope is commonly mounted on an equatorial mount, such as the Sky-Watcher EQ6-R Pro, which is ideal for astrophotography purposes. The telescope’s azimuth, determined by its 25-inch diameter, influences the amount of light gathered and the quality of images produced, further enhancing its observational capabilities. The cost of a 9.25-inch telescope can range from $500 to over $1000, with high-end models costing even more, reflecting its advanced features and performance.

What is a 9.25-inch refractor telescope?

A 9.25-inch refractor telescope is a powerful optical instrument designed for observing various celestial objects with exceptional clarity and detail. Its light-gathering ability is a standout feature, collecting 235 times more light than the human eye, enabling astronomers to explore the depths of the night sky with unparalleled precision. The telescope’s objective lens, typically made of high-quality optical glass such as ED or apochromatic glass, plays a crucial role in gathering and focusing light from distant objects, ensuring sharp and color-accurate images.

With a 9.25-inch aperture, this refractor telescope boasts a significant light-gathering capacity, allowing for brighter and sharper views of celestial phenomena. The telescope’s focal length determines its magnification capabilities, with longer focal lengths providing higher magnification for detailed observations. By using a range of eyepieces, observers can adjust the magnification and field of view to suit their viewing preferences.

The telescope’s length and weight, ranging from 18 to 25 pounds, make it a relatively compact and portable instrument suitable for both backyard stargazing and more advanced astronomical pursuits. A star diagonal enhances the viewing experience by providing a comfortable viewing position and correcting image orientation, while a dew shield prevents moisture buildup on the lens during humid nights.

Equipped with an azimuth mount for easy movement in both vertical and horizontal directions, a 9.25-inch refractor telescope is ideal for amateur astronomers looking to track and observe celestial objects with precision. The telescope’s finder scope aids in locating and centering objects before viewing them through the main telescope, while its wide field of view ensures accurate aiming.

In summary, a 9.25-inch refractor telescope combines exceptional light-gathering ability, high-quality optics, and user-friendly features to offer a rewarding viewing experience for astronomers of all levels. Its ability to collect and focus light from the cosmos, coupled with its versatile magnification options and portable design, make it a valuable tool for exploring the wonders of the universe.

What is a 9.25-inch reflector telescope?

A 9.25-inch reflector telescope is a type of telescope known for its exceptional light-gathering ability, which allows it to capture celestial wonders with impressive detail. The aperture of the telescope, which is 9.25 inches or 235 mm in diameter, determines its light-gathering power and resolution. The larger aperture enables the telescope to observe faint objects with remarkable clarity.

The cost of a 9.25-inch reflector telescope varies widely, ranging from $300 to $20,000 USD, making it accessible to both amateur and seasoned astronomers. Its focal length, which depends on the specific lens and camera system used, enhances its observational capabilities by providing a window into the far reaches of the universe.

The telescope’s azimuth or equatorial feature allows for precise movement and tracking of celestial objects, ensuring a seamless stargazing experience. Eyepieces are an essential component of the telescope, as they magnify the image collected by the primary mirror, enabling detailed observation of distant celestial bodies.

The telescope’s portability, thanks to its manageable weight and dimensions, makes it a versatile companion for all levels of astronomers. With a field of view ranging from 1 to 2 degrees, this telescope offers a wide perspective of the cosmos. Its focal ratio, calculated by dividing the focal length by the aperture diameter, results in a specific f-number, such as f/8 or f/10, further enhancing its observational capabilities.

What can you see with a 9.25-inch telescope?

With a 9.25-inch telescope, you can observe planets such as Jupiter, Saturn, and Mars in great detail, including their moons and surface features. Deep-sky objects such as galaxies, nebulae, and star clusters can also be observed due to the telescope’s high light-gathering power and resolution.

Types and Technical Specifications of 9.25-inch telescopes

Types (Optical Design)

Modified SCT: Example: Celestron 9.25″ EdgeHD Advanced VX Telescope – CE-12033, Celestron CGX-L Equatorial 9.25″ EdgeHD Telescope Bundle – CE-12075, Celestron CGEM-II 925 EdgeHD Telescope Bundle – CE-12018, CE-12056, Celestron CPC Deluxe 925 EdgeHD Telescope Bundle – CE-11008

SCT: Example:Celestron CGEM II· 925 Schmidt-Cassegrain Telescope Bundle – CE- 12011, Celestron CGX 925 Schmidt-Cassegrain Telescope Bundle – CE-12051, Celestron NexStar Evolution 9.25″ Computerized Telescope, Celestron 9.25″ SCT Advanced VX, Celestron CPC 925 Computerized Telescope Bundle – CE-11074-XLT, Celestron C· 9.25 SCT OTA with CGE Mount Plate

Corrected Dall Kirkham: Example:Takahashi Mewlon 250CRS w/ Built-In Corrector & Active Focus

Modified Cassegrain: Example: Celestron 9.25″ EdgeHD OTA with CGE Dovetail Plate

Technical Specifications

Aperture: 9.25-inch (235 mm)

Focal Length: 2350-2500 mm 

Focal ratio: f/10

Highest Magnification: 406-555x

Light Gathering Power: 841-1127x

Price: 1,899-8,320$

Images taken with 9.25-inch telescopes

Examples of 9.25-inch telescopes

• Celestron 9.25″ EdgeHD Advanced VX Telescope – CE-12033
• Celestron CGEM II· 925 Schmidt-Cassegrain Telescope Bundle – CE- 12011
• Takahashi Mewlon 250CRS w/ Built-In Corrector & Active Focus (9.75’’ aperture)
• Celestron CGX-L Equatorial 9.25″ EdgeHD Telescope Bundle – CE-12075
• Celestron CGEM-II 925 EdgeHD Telescope Bundle – CE-12018
• Celestron CGX 925 Schmidt-Cassegrain Telescope Bundle – CE-12051
• Celestron CGX 925 EdgeHD Telescope Bundle – CE-12056
• Celestron NexStar Evolution 9.25″ Computerized Telescope
• Celestron 9.25″ SCT Advanced VX Telescope Bundle – CE-12046
• Celestron 9.25″ EdgeHD OTA with CGE Dovetail Plate
• Celestron CPC 925 Computerized Telescope Bundle – CE-11074-XLT
• Celestron C· 9.25 SCT OTA with CGE Mount Plate
• Celestron CPC Deluxe 925 EdgeHD Telescope Bundle – CE-11008

How do 9.25-inch telescopes compare to other size telescopes

9.25-inch vs 10-inch telescope

9.25-inch telescopes have less aperture than the 10-inch scopes. They offer a focal ratio of f/3.9-f/10 whereas the 9.25-inch telescopes provide f/10. Besides, 9.25-inch telescopes offer a focal length of 2350-2500 mm whereas the 10-inch telescopes vary from 1000-2500 mm in focal lengths.

9.25-inch vs 11-inch telescopes

9.25-inch telescope has less aperture than the 11-inch scopes. 9.25 telescope offers a focal ratio of f/10 whereas the 11-inch telescopes vary from f/2.2-f/10. Besides, 11-inch telescopes offer a focal length of 620-2800 mm whereas the 9.25-inch telescopes start from 2350 mm to 2500 mm in focal lengths. Moreover, 9.25-inch telescopes provide 406-555x the highest magnification, whereas 11-inch telescopes can magnify up to 558-558.8x..

9.25-inch vs 12-inch telescope

9.25-inch telescopes provide focal lengths of 2350-2500 mm (f/3.93- f/5), while 12-inch telescopes vary in focal lengths from 1200-1525 mm (f/3.93- f/5). 9.25-inch telescopes provide the highest magnification of 406-555x, whereas 12-inch telescopes can magnify 600x.

9.25-inch vs 14-inch telescope

14-inch telescopes provide a focal length of 2463-3916 mm with a focal ratio of  f/6.7-f/11. In contrast, 9.25-inch telescopes vary from  2350-2500 mm in focal length with a focal ratio of f/10. However, the price of the 14-inch telescope is three times that of the 9.25-inch telescope. Moreover, 9.25-inch telescopes provide 406-555x highest magnification, which increases to 710x-840x in the case of 14-inch telescopes.