8-inch Telescopes (203mm)
What is a 8-inch telescope?
An 8-inch telescope is a powerful optical instrument designed for observing celestial objects with exceptional detail and clarity. With over 800 times the light-gathering power compared to the naked eye, an 8-inch telescope can discern objects as close as 1.16 arcseconds apart, making it ideal for observing planets, stars, galaxies, and deep-sky objects. The aperture of an 8-inch telescope, which is the diameter of its objective, plays a crucial role in its performance by allowing more light to enter the telescope, resulting in brighter and clearer images. The gathering ability of an 8-inch telescope is significantly greater than the naked eye, making it suitable for observing double stars and revealing previously undetected binaries. The focal length of an 8-inch telescope can be calculated by multiplying the focal ratio by the aperture diameter, influencing factors such as field of view, magnification, and image brightness. The tripod of an 8-inch telescope provides stability and support for precise and steady observations of celestial objects in the night sky. Eyepieces in an 8-inch telescope offer varying levels of magnification, clarity, and field of view, allowing astronomers to adjust their observations accordingly. The average weight of an 8-inch telescope is around 50 pounds, making it portable and easy to transport to different observation sites. The field of view of an 8-inch telescope can range from approximately 9.2 degrees to a specific value calculated based on the telescope’s focal length and eyepiece being used, providing astronomers with a wide perspective of the night sky. The azimuth of an 8-inch telescope facilitates horizontal movement and tracking of celestial objects, aiding in their observation. The price range for an 8-inch telescope typically falls between $500 and $4000, offering a range of options for astronomers with different budgets. The most common mount used for an 8-inch telescope is the German equatorial mount, specifically the Losmandy GM8, providing stability and precision during observations. In conclusion, an 8-inch telescope is a versatile and powerful instrument that combines advanced optical design with innovative features to deliver exceptional performance in observing a wide range of celestial objects.
What is a 8-inch refractor telescope?
An 8-inch refractor telescope is a powerful optical instrument that excels in providing sharp and detailed images of celestial objects. It boasts an excellent light-gathering ability, thanks to its significant aperture size of 8 inches, which allows for the observation of faint objects in the night sky with impressive resolution and image quality. The telescope’s objective lens plays a crucial role in gathering and focusing light from celestial sources, contributing to its impressive resolution and image quality.
In terms of cost, an 8-inch refractor telescope typically falls within the price range of $500 to $2000, making it an accessible option for astronomy enthusiasts. The telescope’s focal length, which is approximately 1200mm, enables high magnification capabilities of up to 250x, offering detailed views of distant objects.
The telescope is equipped with eyepieces that determine magnification and field of view, enhancing the observer’s viewing experience. Its tripod provides stability and support, allowing for precise adjustments during observations. Additionally, the telescope features a star diagonal that facilitates comfortable viewing by redirecting the light path.
The tube of an 8-inch refractor telescope houses the optics, protecting them and contributing to the telescope’s performance. The telescope’s 6 feet length and 50-pound weight make it a manageable yet powerful instrument for astronomical observations. It utilizes a quality achromatic or apochromatic lens to minimize chromatic aberration and produce corrected images.
With a focal ratio of f/6, the 8-inch refractor telescope strikes a balance between light-gathering capacity and field of view, making it a versatile instrument for various observation purposes. It is typically mounted on an equatorial or azimuth mount, allowing for precise tracking of celestial objects.
What is a 8-inch reflector telescope?
An 8-inch reflector telescope is a type of reflecting telescope that uses a combination of curved mirrors to reflect light and form an image. The primary mirror of an 8-inch reflector telescope has a diameter of 8 inches, providing significant light-gathering ability. This feature allows for the observation of faint objects not visible to the naked eye, making it suitable for observing celestial objects such as Jupiter’s cloud bands, the Great Red Spot, Galilean moons, faint objects, deep-sky objects, and star clusters.
The gathering ability of an 8-inch reflector telescope is significantly better than smaller telescopes, making it a good choice for observing celestial objects. This ability depends on the specific design and type of reflector telescope, with the aperture being a significant factor. The aperture in an 8-inch reflector telescope determines the amount of light collected and the level of detail that can be resolved in celestial objects, ultimately enhancing the viewing experience for astronomers.
The focal length of an 8-inch reflector telescope can range from 800mm to 1220mm, with the ideal focal ratio being around f/6 to f/8. The optical design of an 8-inch reflector telescope is focused on gathering and focusing light using mirrors, providing better light-gathering power and resolution for viewing celestial objects.
The tube of an 8-inch reflector telescope is typically made of metal and/or glass, with a Schmidt corrector plate to correct for spherical aberration. The mirrors of an 8-inch reflector telescope are coated with an anti-reflective coating to enhance their performance.
An 8-inch reflector telescope can be portable due to its compact size, lightweight materials, and features like portable mounts or bases that make it easier to transport and set up in different locations. The average weight of an 8-inch reflector telescope is typically around 20-30 pounds.
The field of view for an 8-inch reflector telescope can vary depending on the specific model and eyepiece used, but it is typically around 9.2 degrees. The maximum magnification of an 8-inch reflector telescope is approximately 400x, with the magnification power varying depending on the focal length of the objective and eyepiece.
A Dobsonian-style mount is recommended for an 8-inch reflector telescope, providing stability and ease of use. The secondary mirror in an 8-inch reflector telescope redirects the light gathered by the primary mirror towards the eyepiece or camera, allowing for viewing or capturing of the image.
What can you see with a 8-inch telescope?
With an 8-inch telescope, you can observe the planets of our solar system in great detail, including the rings of Saturn, the Great Red Spot on Jupiter, and the ice caps on Mars. You can also see deep-sky objects such as galaxies, nebulae, and star clusters. For example, you can observe the Andromeda Galaxy, the Orion Nebula, and the Hercules Globular Cluster. An 8-inch telescope can also reveal details on the Moon’s surface, such as craters, mountains, and valleys, providing a stunning view of our natural satellite.
Types and Technical Specifications of 8-inch telescopes
Types (Optical Design)
Newtonian: Example: Meade 8″ f/4 LX85 Astrograph Reflector Optical Tube, Meade 8″ f/4 LX85 Astrograph Reflector Telescope, Starfield f/4 Imaging Newtonian – 8″, Celestron Starsense Explorer 8″ Dobsonian Smartphone Telescope, Orion 8″ f/4 Newtonian Reflector Astrograph, TPO 8″ f/4 Newtonian Reflecting OTA Telescope.
Cassegrain: Example: Meade 8″ f/10 LX85 ACF Telescope with Mount and Tripod, Meade 8″ f/10 LX85 ACF Optical Tube Assembly.
RASA: Example: Celestron RASA 8″ Telescope w/ AVX Mount Bundle – CE-12032, Celestron CGX 8-Inch RASA Telescope Package, Celestron RASA 8″ Telescope w/ Computerized CGEM-II Mount Bundle – CE-12020, Celestron RASA 8″ f/2 OTA.
Modified SCT: Example:Meade LX200-ACF 8″ f/10 Telescope – without Tripod, Celestron CGX 800 EdgeHD Telescope Bundle – CE-12055, Celestron NexStar Evolution 8″ EdgeHD with StarSense, Celestron 8″ EdgeHD Advanced VX Telescope Bundle – CE-12031, Meade 8″ LX200-ACF f/10 OTA Only w/ UHTC, Meade 8″ ACF LX90 Telescope, Celestron CPC Deluxe 800 EdgeHD Telescope.
Ritchey Chretien: Example: Orion 8″ f/8 Ritchey Chretien Reflecting OTA Telescope, TPO 8″ f/8 Ritchey Chretien Steel Astrograph with TPO 2″ Focuser, iOptron Photron 200 RC OTA,TPO 8″ Carbon Fiber f/8 Ritchey Chretien Reflecting OTA Telescope.
Dobsonian: Example: Orion SkyQuest XT8 Classic Dobsonian Telescope Kit, Sky-Watcher Classic 200P f/5.9 Dobsonian Telescope, Sky-Watcher Flextube 200P f/5.9 8″ Dobsonian, Orion SkyQuest XT8 Classic Dobsonian Telescope, Sky-Watcher 8″ GoTo Collapsible Dobsonian Telescope.
SCT: Example: Celestron CGEM II· 800 Schmidt-Cassegrain Telescope – CE- 12010, Celestron CGX 800 Computerized Telescope, Celestron Advanced VX 8″ Schmidt-Cassegrain Telescope Bundle – CE-12026, Celestron CPC 800 GPS (XLT) Computerized Telescope Bundle – CE-11073-XLT, Celestron C· 8 -A XLT CGE Optical Tube Assembly, Celestron NexStar Evolution 8″ Computerized Telescope, Celestron NexStar 8SE Computerized Telescope.
Dall Kirkham: Example: Takahashi Mewlon-210 f/11.5 Dall Kirkham Reflecting OTA Telescope.
Technical Specifications
Aperture: 8-inch (203 mm)
Focal Length: 800-2415 mm
Focal ratio: f/4-f/11.5
Highest Magnification: 300-480
Light Gathering Power: 816-900x
Price: 570-5,000$
Images taken with 8-inch telescopes
Examples of 8-inch telescopes
- Meade 8″ f/4 LX85 Astrograph Reflector Optical Tube
- Meade 8″ f/10 LX85 ACF Telescope with Mount and Tripod
- Meade 8″ f/4 LX85 Astrograph Reflector Telescope
- Starfield f/4 Imaging Newtonian – 8″
- Celestron RASA 8″ Telescope w/ AVX Mount Bundle – CE-12032
- Celestron CGX 8-Inch RASA Telescope Package
- Celestron RASA 8″ f/2 OTA
- Meade LX200-ACF 8″ f/10 Telescope – without Tripod
- Orion 8″ f/8 Ritchey Chretien Reflecting OTA Telescope
- Orion SkyQuest XT8 Classic Dobsonian Telescope Kit
- Celestron CGEM-II 800 EdgeHD Telescope – CE-12017
- Celestron CGEM II· 800 Schmidt-Cassegrain Telescope – CE- 12010
- Celestron CGX 800 Computerized Telescope
- Celestron CGX 800 EdgeHD Telescope Bundle – CE-12055
- Celestron NexStar Evolution 8″ EdgeHD with StarSense
- Sky-Watcher Classic 200P f/5.9 Dobsonian Telescope
- TPO 8″ f/8 Ritchey Chretien Steel Astrograph with TPO 2″ Focuser
- Celestron 8″ EdgeHD Advanced VX Telescope Bundle – CE-12031
- Celestron Advanced VX 8″ Schmidt-Cassegrain Telescope Bundle – CE-12026
- Sky-Watcher Flextube 200P f/5.9 8″ Dobsonian Telescope
- SKU : SW-S11700
- Celestron CPC 800 GPS (XLT) Computerized Telescope Bundle – CE-11073-XLT
- Orion SkyQuest XT8 Classic Dobsonian Telescope
- Meade 8″ f/10 LX85 ACF Optical Tube Assembly
- Celestron Starsense Explorer 8″ Dobsonian Smartphone Telescope
- Orion 8″ f/4 Newtonian Reflector Astrograph
- iOptron Photron 200 RC OTA
- Sky-Watcher 8″ GoTo Collapsible Dobsonian Telescope
- TPO 8″ Carbon Fiber f/8 Ritchey Chretien Reflecting OTA Telescope
- Takahashi Mewlon-210 f/11.5 Dall Kirkham Reflecting OTA Telescope
- Celestron C· 8 -A XLT CGE Optical Tube Assembly
- Meade 8″ LX200-ACF f/10 OTA Only w/ UHTC
- TPO 8″ f/4 Newtonian Reflecting OTA Telescope
- Meade 8″ ACF LX90 Telescope
- Celestron CPC Deluxe 800 EdgeHD Telescope
- Celestron NexStar Evolution 8″ Computerized Telescope
- Celestron NexStar 8SE Computerized Telescope
How do 8-inch telescopes compare to other size telescopes
8-inch vs 9.25-inch telescope
8-inch telescopes provide a focal length of 800-2415 mm with a focal ratio of f/4-f/11.5. 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 9.25-inch scope is three times that of the 8-inch scope. Moreover, 9.25-inch telescopes provide 406-555x highest magnification, which is 300-480x in the case of 8-inch telescopes.
| 8-inch telescope | 9.25-inch telescope | |
| Aperture | 8-inch (203 mm) | 9.25-inch (235 mm) |
| Focal Ratio | f/4-f/11.5 | f/10 |
| Focal Length | 800-2415 mm | 2350-2500 mm |
| Highest Magnification | 300-480x | 406-555x |
| Price | 570-5,000$ | 1,899-8,320$ |
8-inch vs 10-inch telescope
8-inch telescopes have less aperture than the 10-inch telescopes. They offer a focal ratio of f/3.9-f/10 whereas the 8-inch telescopes provide f/4-f/11.5. Besides, 8-inch telescopes offer a focal length of 800-2415 mm whereas the 10-inch telescopes vary from 1000-2500 mm in focal lengths.
| 8-inch telescope | 10-inch telescope | |
| Aperture | 8-inch (203 mm) | 10-inch (254 mm) |
| Focal Ratio | f/4-f/11.5 | f/3.9-f/10 |
| Focal Length | 800-2415 mm | 1000-2500 mm |
| Highest Magnification | 300-480x | 500-600x |
| Price | 570-5,000$ | 630-10,000$ |
8-inch vs 11-inch telescopes
8-inch telescope has less aperture than the 11-inch telescopes. They offer a focal ratio of f/4-f/11.5 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 8-inch telescopes start from 800 mm to 2415 mm mm in focal lengths. Moreover, 8-inch telescopes provide 300-480x the highest magnification, whereas 11-inch telescopes can magnify up to 558-558.8x..
| 8-inch telescope | 11-inch telescopes | |
| Aperture | 8-inch (203 mm) | 11-inch (279 mm) |
| Focal Ratio | f/4-f/11.5 | f/2.2-f/10 |
| Focal Length | 800-2415 mm | 620-2800 mm |
| Highest Magnification | 300-480x | 558-558.8x |
| Price | 570-5,000$ | 2,400-6,500$ |
8-inch vs 12-inch telescope
8-inch telescopes provide focal lengths of 800-2415 mm (f/4-f/11.5), while 12-inch telescopes vary in focal lengths from 1200-1525 mm (f/3.93- f/5). 8-inch telescopes provide the highest magnification of 300-480x, whereas 12-inch telescopes can magnify 600x.
| 8-inch telescope | 12-inch telescope | |
| Aperture | 8-inch (203 mm) | 12-inch (305 mm) |
| Focal Ratio | f/4-f/11.5 | f/3.93- f/5 |
| Focal Length | 800-2415 mm | 1200-1525 mm |
| Highest Magnification | 300-480x | 600x |
| Price | 570-5,000$ | 1,200-2,550$ |
