In accordance with §11 PAngV (German ordinance regulating the indication of Prices), the last offer price shows the lowest price of the last 30 days after all usual direct discount deductions. Discounts such as cashback or trade-in, which are calculated or paid out after the purchase or by third parties without a contractual relationship with Hifi Foto Koch GmbH (service providers, agencies, manufacturers, etc.) or which require further action, are not included.
RASA 8 inch - Rowe-Ackermann Schmidt Astrograph
The transportable astrograph from Celestron, the 8 inch Rowe-Ackermann Schmidt Astrograph (RASA), can capture spectacular deep-sky wide-field images in seconds. This incredibly fast f/2.0 system is the perfect telescope for modern astronomical CMOS color cameras, smaller CCD cameras and mirrorless cameras.
Thanks to the large focal ratio and patented optical design, you can produce sharp, detailed images and in many cases completely dispense with an autoguider. With a weight of only 7.7 kg (17 pounds), it is easy to transport the 8 inch RASA to even the most remote locations.
RASA performancefor everyone
The 8 inch RASA is a telescope designed purely for photography, providing a flat field of view without optical aberrations and thus showing extremely sharp stars over a large field of view. It provides astronomical images with impressive "depth" and avoids the problems typically associated with longer focal length (and slower focal ratio) instruments.
The latest addition to the RASA family, the 8-inch aperture is a much more portable and affordable version of the RASA 11, which was launched to great acclaim in 2014. With the 8-inch RASA, the benefits of the RASA design are now available to a wider range of astrophotographers. It shares many features with its "big brother" RASA 11, including the integrated cooling system, the internal filter holder and the robust CGE dovetail mount.
The 8-inch RASA is designed exclusively for photography and cannot be used visually. The focal plane is located at the front of the optical system, so the telescope cannot accommodate a conventional eyepiece.
Shorter exposure times and virtual "real-time" observation
Because it is an f/2.0 optical system, astrophotographers can use shorter exposure times to capture details in faint objects. In combination with sensitive cameras and the right "live stacking" software, near-live observations are also possible with the 8" RASA: you can view and stack the images on a computer instantly, making them brighter and more detailed than with the naked eye - even compared to much larger telescopes!
As shorter exposure times are possible, your mount does not have to track with high precision over longer periods of time. The relatively short focal length of 400 mm of the 8 inch RASA further reduces the tracking requirements. In many cases, autoguiding is not necessary. With a weight of only 7.7 kg (17 pounds), this telescope fits perfectly with a variety of commercially available mounts.
Ultrastable Focusing System
With the introduction of the 8 inch RASA, Celestron introduces a new focusing mechanism that reduces the backlash of the primary mirror when focusing, slewing or tracking the astrograph. Focusing is easier, more accurate and more stable than ever. The key to this ultra-stable focusing system is two groups of precision bearings that are precisely aligned and tested during assembly for optimal results.
Unique optical design
The patented RASA design (US 2016/0299331 A1) consists of Schmidt plate, primary mirror, lens group and optical window. The lens group consists of four elements and uses rare earths. Unlike many other telescopes, which only perform well in visible light (400-700nm), the 8-inch RASA is designed for a wider spectral range, from 390-800 nm. This allows more light from celestial objects to be collected and imaged sharply.
With many optical systems, it is irrelevant for the imaging quality whether an additional flat glass such as a filter is used. With extremely fast systems such as the RASA, the situation is different. Our developers have solved this problem by providing the RASA with an optical window that can be removed and replaced with a filter. This means that the image quality remains at the highest level even if you use a filter or the camera has its own optical window. Celestron offers a filter against light pollution which was specially developed for the 8" RASA and which replaces the optical window.
All refractive optical surfaces are StarBright-XLT-coated, the primary mirror has an improved aluminum coating. This ensures high transmission for the entire system. Compared to the HyperStar system for Schmidt-Cassegrains, the RASA 8 delivers better optical performance and superior illumination.
Developed for the most modern cameras
In contrast to the larger RASAs, which are optimized for DSLR and large CCD cameras, the 8-inch model was developed for astronomical CMOS colour cameras, smaller CCD cameras and mirrorless cameras. The telescope does not work with standard DSLR cameras due to the available back focus. It is optimized for sensors with a diagonal of up to 22 mm and still offers good performance on sensors with a diagonal of up to 32 mm. The APS-C format sensors used in many mirrorless cameras are a good choice. 42mm full-frame sensors also work in principle, but performance at the edges of the sensor is poor and field illumination is reduced. In addition, we do not recommend combining the RASA 8 with a camera body with a diameter of more than 10cm.
RASA 8 inch - Rowe-Ackermann Schmidt Astrograph
The transportable astrograph from Celestron, the 8 inch Rowe-Ackermann Schmidt Astrograph (RASA), can capture spectacular deep-sky wide-field images in seconds. This incredibly fast f/2.0 system is the perfect telescope for modern astronomical CMOS color cameras, smaller CCD cameras and mirrorless cameras.
Thanks to the large focal ratio and patented optical design, you can produce sharp, detailed images and in many cases completely dispense with an autoguider. With a weight of only 7.7 kg (17 pounds), it is easy to transport the 8 inch RASA to even the most remote locations.
RASA performancefor everyone
The 8 inch RASA is a telescope designed purely for photography, providing a flat field of view without optical aberrations and thus showing extremely sharp stars over a large field of view. It provides astronomical images with impressive "depth" and avoids the problems typically associated with longer focal length (and slower focal ratio) instruments.
The latest addition to the RASA family, the 8-inch aperture is a much more portable and affordable version of the RASA 11, which was launched to great acclaim in 2014. With the 8-inch RASA, the benefits of the RASA design are now available to a wider range of astrophotographers. It shares many features with its "big brother" RASA 11, including the integrated cooling system, the internal filter holder and the robust CGE dovetail mount.
The 8-inch RASA is designed exclusively for photography and cannot be used visually. The focal plane is located at the front of the optical system, so the telescope cannot accommodate a conventional eyepiece.
Shorter exposure times and virtual "real-time" observation
Because it is an f/2.0 optical system, astrophotographers can use shorter exposure times to capture details in faint objects. In combination with sensitive cameras and the right "live stacking" software, near-live observations are also possible with the 8" RASA: you can view and stack the images on a computer instantly, making them brighter and more detailed than with the naked eye - even compared to much larger telescopes!
As shorter exposure times are possible, your mount does not have to track with high precision over longer periods of time. The relatively short focal length of 400 mm of the 8 inch RASA further reduces the tracking requirements. In many cases, autoguiding is not necessary. With a weight of only 7.7 kg (17 pounds), this telescope fits perfectly with a variety of commercially available mounts.
Ultrastable Focusing System
With the introduction of the 8 inch RASA, Celestron introduces a new focusing mechanism that reduces the backlash of the primary mirror when focusing, slewing or tracking the astrograph. Focusing is easier, more accurate and more stable than ever. The key to this ultra-stable focusing system is two groups of precision bearings that are precisely aligned and tested during assembly for optimal results.
Unique optical design
The patented RASA design (US 2016/0299331 A1) consists of Schmidt plate, primary mirror, lens group and optical window. The lens group consists of four elements and uses rare earths. Unlike many other telescopes, which only perform well in visible light (400-700nm), the 8-inch RASA is designed for a wider spectral range, from 390-800 nm. This allows more light from celestial objects to be collected and imaged sharply.
With many optical systems, it is irrelevant for the imaging quality whether an additional flat glass such as a filter is used. With extremely fast systems such as the RASA, the situation is different. Our developers have solved this problem by providing the RASA with an optical window that can be removed and replaced with a filter. This means that the image quality remains at the highest level even if you use a filter or the camera has its own optical window. Celestron offers a filter against light pollution which was specially developed for the 8" RASA and which replaces the optical window.
All refractive optical surfaces are StarBright-XLT-coated, the primary mirror has an improved aluminum coating. This ensures high transmission for the entire system. Compared to the HyperStar system for Schmidt-Cassegrains, the RASA 8 delivers better optical performance and superior illumination.
Developed for the most modern cameras
In contrast to the larger RASAs, which are optimized for DSLR and large CCD cameras, the 8-inch model was developed for astronomical CMOS colour cameras, smaller CCD cameras and mirrorless cameras. The telescope does not work with standard DSLR cameras due to the available back focus. It is optimized for sensors with a diagonal of up to 22 mm and still offers good performance on sensors with a diagonal of up to 32 mm. The APS-C format sensors used in many mirrorless cameras are a good choice. 42mm full-frame sensors also work in principle, but performance at the edges of the sensor is poor and field illumination is reduced. In addition, we do not recommend combining the RASA 8 with a camera body with a diameter of more than 10cm.
When creating your customer opinion and/or uploading media (e.g. images, videos, audio files, texts, documents, etc.), please observe our guidelines:
Each customer opinion is editorially checked before publication. Please ensure, among other things, that
By submitting your customer opinion and/or uploading media, you agree to these guidelines and terms of use.
These terms of use apply to the participation in and use of the customer ratings of Hifi Foto Koch GmbH. In the event of conflicts with the general terms and conditions or data protection regulations, these terms of use shall take precedence.
By submitting a customer rating and/or an upload of media (e.g. pictures, videos, audio files, texts, documents etc.) you assure that
You provide your content free of charge and are not entitled to any form of remuneration or compensation. There is no entitlement to publication.
Submitted customer opinions and uploaded media are usually reviewed and published within a few working days. All transferable rights of use of the content provided by you are transferred to Hifi Foto Koch GmbH and its current or future partners and representatives (including but not limited to affiliated companies, service providers, search engines, employees, agencies, branches, joint ventures, suppliers). The content may be used, modified and published by the aforementioned parties at their own discretion without any restrictions in terms of time, content and location. Promotional use is also permitted. The content may be edited or deleted if it violates the guidelines for ratings and community media as well as these terms of use or if it makes sense for the respective purpose. It is also possible to shorten the content at any time and without giving reasons.
Hifi Foto Koch GmbH and its current or future partners and agents do not warrant the ability to modify or delete the content you submit, should you wish to do so.
You transfer the rights and licence of your content to Hifi Foto Koch GmbH and its current or future partners and representatives. You grant Hifi Foto Koch GmbH and its current or future partners and representatives, the unrestricted right to your customer opinion (rating text, nickname, star rating, recommendation, etc.) as well as to your media (e.g. images, videos, audio files, texts, documents, etc.; incl. the indication of the author, description, etc.) to use, change, store, delete, shorten, modify, adapt, translate, copy, pass on, sell and distribute worldwide in any form, any medium, in any technology. Personal data (e-mail address, address, contact details) will not be passed on to third parties.
You assume full responsibility for your content. You agree to indemnify Hifi Foto Koch GmbH and its current or future affiliates and agents for all costs, including attorneys' fees, any damages, consequential damages of any kind, claims and demands arising from your failure to comply with the Review and Community Media Guidelines and these Terms of Use.
By submitting your customer opinion and/or uploading media, you agree to the Review and Community Media Guidelines and Terms of Use. By providing your email address, you agree that Hifi Foto Koch GmbH and its current or future partners and agents may send you status information of your customer opinion by email.
Data protection notice
When using the homepage including the submission of ratings and the upload of media, so-called personal data is processed by HiFi Foto Koch GmbH in the sense of Article 6 paragraph 1 DSGVO. Personal data is information that can be directly or indirectly assigned to you or can be assigned to you. In addition to the information entered by you, such as the name, e-mail and description, this data can also be data related to your customer account, IP addresses, access times, accessed URL, sources, browsers used, operating systems and devices, the name of your access provider as well as others. A full overview of data processing and privacy information can be found at https://www.fotokoch.fr/privacy.html.