Telescope Nerd » Sizes » 6-inch Telescopes (150mm)

6-inch Telescopes (150mm)

6-inch telescopes are basically for amateurs. On average, they provide 162-1800 mm focal lengths, and a range of focal ratios from f/3.9-f/10. They can magnify objects 295-320x times the human eye. They also can resolve double stars at 0.76 arcsec. You can get 6-inch telescopes from different brands in the price range of 310$ – 15,070$.

What is a 6-inch telescope?

A 6-inch telescope refers to a telescope having an aperture (the diameter of the objective lens) of 6-inch (150 mm). A 6-inch telescope is considered to be in the category of a medium telescope. 

What can you see with a 6-inch telescope?

  • The Moon and its craters 
  • Jupiter with its cloud belts, and the Great Red Spot
  • Saturn and its bands, the Cassini Division
  • Uranus and Neptune
  • Galaxies like M83, Whirlpool Galaxy, M81 and M82
  • Globular star clusters like M5, M13, M15, and M92
  • Nebulae like NGC 7027 in Cygnus, etc

Types and Technical Specifications of 6-inch telescope

Types (Optical Design)

Triplet Refractor: Example: Sky-Watcher Esprit 150mm ED Triplet APO Refractor, Takahashi TOA-150B Double ED Triplet Refractor Telescope – Heavy-Duty 4″ Focuser

Doublet Refractor: Example: Sky-Watcher Evostar 150DX f/8 Doublet Refracting Telescope,  Celestron Advanced VX 6″ Refractor Telescope

SCT: Example: Celestron NexStar Evolution 6″ Computerized Telescope, Celestron Advanced VX 6″ Schmidt-Cassegrain Telescope Bundle – CE-12079, Celestron C· 6 -A-XLT Schmidt-Cassegrain OTA with CG- 5 Mount Plate, Celestron NexStar 6SE Computerized Telescope

Maksutov Cassegrain: Example: Sky-Watcher 150mm Maksutov Cassegrain Telescope OTA, iOptron 150mm Maksutov Cassegrain OTA

Ritchey Chretien: Example: Orion 6″ f/9 Ritchey Chretien Reflecting OTA Telescope, TPO 6″ f/9 Ritchey Chretien Reflecting OTA Telescope, iOptron Photron 150 RC OTA

Doublet Refractor: Example: Sky-Watcher Evostar 150 f/8 Apochromatic Refracting Telescope, 

Dobsonian: Example: Sky-Watcher Heritage 150 Tabletop Dobsonian, Takahashi Epsilon E-160ED 160mm ED Astrograph OTA, Orion SkyQuest XT6 Classic Dobsonian, Orion 6″ F/4.1 Newtonian Astrograph Reflector Telescope, Sky-Watcher Classic 150P f/7.9 Dobsonian Telescope

Cassegrain: Example: Meade 6″ f/10 LX85 ACF Optical Tube Assembly, Meade 6″ f/10 LX85 ACF Telescope with Mount and Tripod

Newtonian: Example: Sharpstar 15028HNT, Sky-Watcher Virtuoso GTi 150 Tabletop GoTo Dobsonian, Meade 6″ f/4.1 LX85 Reflector Optical Tube Assembly, Meade LX85 6″ Newtonian Astrograph w/Audiostar Equatorial Mount, TPO 6″ f/6 Newtonian Reflecting OTA Telescope, Celestron Advanced VX 6″ Newtonian Telescope, TPO 6″ f/4 Newtonian Reflecting OTA Telescope, Sky-Watcher Quattro 150P Imaging Newtonian Telescope, Celestron Omni XLT 150 Telescope – Reflector

Technical Specifications

Aperture: 6-inch (150 mm)

Focal Length: 162-1800 mm 

Focal ratio: f/3.9-f/10

Highest Magnification: 295-320x

Light Gathering Power: 459-522x

Price: 310-15,070$

Images taken with 6-inch telescopes

Examples of 6-inch telescopes

  • Sharpstar 15028HNT
  • Sky-Watcher Virtuoso GTi 150 Tabletop GoTo Dobsonian
  • Meade 6″ f/10 LX85 ACF Optical Tube Assembly
  • Meade 6″ f/4.1 LX85 Reflector Optical Tube Assembly
  • Meade 6″ f/10 LX85 ACF Telescope with Mount and Tripod
  • Meade LX85 6″ Newtonian Astrograph w/Audiostar Equatorial Mount
  • Sky-Watcher Heritage 150 Tabletop Dobsonian
  • Takahashi Epsilon E-160ED 160mm ED Astrograph OTA
  • Sky-Watcher Evostar 150 f/8 Apochromatic Refracting Telescope
  • Orion 6″ f/9 Ritchey Chretien Reflecting OTA Telescope
  • Orion SkyQuest XT6 Classic Dobsonian Telescope Kit
  • Orion 6″ F/4.1 Newtonian Astrograph Reflector Telescope
  • Sky-Watcher 150mm Maksutov Cassegrain Telescope OTA
  • TPO 6″ f/6 Newtonian Reflecting OTA Telescope
  • Celestron Advanced VX 6″ Newtonian Telescope
  • Celestron NexStar Evolution 6″ Computerized Telescope
  • Sky-Watcher Esprit 150mm ED Triplet APO Refractor
  • TPO 6″ f/9 Ritchey Chretien Reflecting OTA Telescope
  • TPO 6″ f/4 Newtonian Reflecting OTA Telescope
  • Celestron Advanced VX 6″ Schmidt-Cassegrain Telescope Bundle – CE-12079
  • iOptron 150mm Maksutov Cassegrain OTA
  • Celestron C· 6 -A-XLT Schmidt-Cassegrain OTA with CG- 5 Mount Plate
  • Takahashi TOA-150B Double ED Triplet Refractor Telescope – Heavy-Duty 4″ Focuser
  • Celestron NexStar 6SE Computerized Telescope
  • Sky-Watcher Evostar 150DX f/8 Doublet Refracting Telescope
  • Celestron Advanced VX 6″ Refractor Telescope
  • Sky-Watcher Quattro 150P Imaging Newtonian Telescope
  • Sky-Watcher Classic 150P f/7.9 Dobsonian Telescope
  • Celestron Omni XLT 150 Telescope – Reflector
  • iOptron Photron 150 RC OTA

How do 6-inch telescopes compare to other size-telescopes

6-inch vs 7-inch telescopes

6-inch telescope has less aperture than the 7-inch telescopes. They offer a focal ratio of f/2.8-f/15 whereas the 6-inch telescopes vary from f/3.9-f/10. Besides, 6-inch telescopes offer a focal length of 162-1800 mm whereas the 7-inch telescopes start from 500 mm to 2700 mm in focal lengths. Moreover, 7-inch telescopes provide 360x the highest magnification, whereas 6-inch telescopes can magnify up to 295-320x.

6-inch telescope7-inch telescopes
Aperture6-inch (150 mm)7-inch (180 mm)
Focal Ratiof/3.9-f/10f/2.8-f/15
Focal Length162-1800 mm500-2700 mm
Highest Magnification295-320x360x
Price310-15,070$1,350-5,500$

6-inch vs 8-inch telescope

8-inch telescopes provide focal lengths of 800-2415 mm (f/4-f/11.5), while 6-inch vary in focal lengths from 162-1800 mm (f/3.9-f/10). On average 8-inch telescopes provide the highest magnification of 300-480x, whereas 6-inch telescopes can magnify 295-320x. 

6-inch telescope8-inch telescope
Aperture6-inch (150 mm)8-inch (203 mm)
Focal Ratiof/3.9-f/10f/4-f/11.5
Focal Length162-1800 mm800-2415 mm
Highest Magnification295-320x300-480x
Price310-15,070$570-5,000$

6-inch vs 9.25-inch telescope

6-inch telescopes provide a focal length of 162-1800 mm with a focal ratio of f/3.9-f/10. In contrast, 9.25-inch telescopes vary from 2350-2500 mm in focal length with a focal ratio of f/10. Moreover, 9.25-inch telescopes provide 406-555x the highest magnification, which is 295-320x in the case of 6-inch telescopes.

6-inch telescope9.25-inch telescope
Aperture6-inch (150 mm)9.25-inch (235 mm)
Focal Ratiof/3.9-f/10f/10
Focal Length162-1800 mm2350-2500 mm
Highest Magnification295-320x406-555x
Price310-15,070$1,899-8,320$

6-inch vs 10-inch telescope

6-inch telescopes have less aperture than the 10-inch telescopes. They offer the same range of focal ratio i.e. f/3.9-f/10. However, 6-inch telescopes offer a focal length of 162-1800 mm whereas the 10-inch telescopes vary from 1000-2500 mm in focal lengths. Though sometimes you can get 10-inch telescopes at a lesser price than a 6-inch scope.

6-inch telescope10-inch telescope
Aperture6-inch (150 mm)10-inch (254 mm)
Focal Ratiof/3.9-f/10f/3.9-f/10
Focal Length162-1800 mm1000-2500 mm
Highest Magnification295-320x500-600x
Price310-15,070$630-10,000$

Similar Posts