For serious astrophotographers, an optical tube that has quality optics and suitable specifications is key to producing successful images. Astrographs come in many different specifications and designs, so each model can be oriented or preferred for a different type of imaging (eg. solar, terrestrial, deep sky etc). Some common designs include the Ritchey-Chrétien, Riccardi Honders, and Catadioptric optical tubes. Choosing an astrograph depends on how the astro-imager wants to observe, what focal length and focal ratio it has, aperture, optical coatings, and how suitable it is for the camera they intend to use.
A key specification very important to consider when choosing an astrograph is focal ratio in relation to aperture. This is an important to remember because focal ratio determines what the magnification and field of view the observor will get. Therefore, if the observor intends to mainly view deep sky objects with lower surface brightnesses, a shorter focal length will reduce magnification and increase field of view since most deep sky objects tend to appear very large but not bright. Astrograph telescopes with slower focal ratios such as an f/12 will provide higher magnification and smaller field of views; better for planetary observing.
FREE SHIPPINGModel#: B07743(48 States)
- BORG 77EDII OTA
- 0.65x reducer
- Total of 6 elements
- 330mm focal length
- 35mm full-frame coverage
Developed by Astro-Tech to make large-format CCD imaging affordable for the amateur astronomer, the Astro-Tech AT10RCF is priced thousands of dollars less than the formerly least-expensive 10” R-C. The Astro-Tech AT10RCF is the first truly affordable large aperture true Ritchey-Chrétien astrograph available from a U. S. company.... Learn MoreFREE SHIPPINGModel#: AT10RCF(48 States)
Optical tubes based upon the Ritchey Chretien design are known very well for their successfull astrophotography, and the 10" optical tube by Astro-Tech is no different! What is different is the price!... Learn MoreFREE SHIPPINGModel#: AT10RC(48 States)
This package is discontinued. We recommend the Celestron package instead.
This Complete Kit includes Scope, Mount, Camera (complete Kit) Camera adapters, Cable release and more........ Learn MoreFREE SHIPPINGModel#: 0605-75-02+6596B002(48 States)
Go after even the most elusive and faint deep-sky targets with the Orion 10" f/8.0 Ritchey-Chretien Astrograph. Featuring virtually coma-free optics for superb imaging performance, the Orion 10" f/8.0 Ritchey-Chretien Astrograph boasts a plethora of deluxe features... Learn MoreModel#: 8961
Takahashi introduced their Epsilon Series flat-field hyperbolic astrographs in the middle 1980’s. The Epsilon-130 was the smallest aperture and most portable of the series. Now Takahashi is re-introducing the new ε-130D digital version of this astrograph.... Learn MoreFREE SHIPPINGModel#: TEK1310(48 States)
Now introducing the NEW Takahashi FSQ106! The FSQ106ED telescope features longer backfocus of 178mm to accommodate most CCD systems... Learn MoreFREE SHIPPINGModel#: FSQ106EDXIII(48 States)
Introducing the Takahashi FSQ-85ED, the newest and smallest member of the FSQ Series of flat field astrographs. Designed from the ground up for digital imaging, the Takahashi Baby “Q” is the go anywhere, portable astrograph.... Learn MoreFREE SHIPPINGModel#: FQK0085(48 States)