MAK vs RASA: Choosing Your Catadioptric Telescope
By Cloud Break Optics | Published: 2026-10-18
Category: Comparisons
Deciding between a Maksutov-Cassegrain and a Rowe-Ackermann Schmidt Astrograph? Learn key differences in speed, aperture, and portability to pick the right catadioptric telescope for your goals.
Quick answer
If you want a versatile, affordable telescope for visual observing and casual imaging, a Maksutov-Cassegrain like the MAK 150mm is a strong choice. For dedicated, fast deep-sky astrophotography with wide fields and sub-arcsecond resolution, the Rowe-Ackermann Schmidt Astrograph (RASA) is purpose-built.
Optical design and speed
Catadioptric telescopes use a combination of lenses and mirrors to fold the optical path, making them compact. The two designs here differ in their primary goal: the Maksutov-Cassegrain prioritizes sharp, color-free views for visual use and planetary imaging, while the Rowe-Ackermann Schmidt Astrograph is optimized for ultra-fast f/2.2 imaging, capturing wide fields with minimal coma and false color.
Aperture and portability trade-offs
A larger aperture collects more light, but also adds weight and cost. The 36 cm RASA offers a massive 36 cm aperture but weighs significantly more and costs over USD 9,700. In contrast, the MAK 150mm provides a 150 mm aperture in a lightweight, affordable package (under USD 600). The RASA 6 strikes a middle ground with a 6-inch aperture at just 8.4 lb, making it portable for mobile imaging sessions.
Decision rules: MAK vs RASA
- Primary use case: Choose a Maksutov-Cassegrain (e.g., MAK 150mm) if your main interest is visual observing, lunar/planetary viewing, or casual imaging. Choose a Rowe-Ackermann Schmidt Astrograph (e.g., RASA 6 or 36 cm) if your priority is deep-sky astrophotography with wide fields and fast capture.
- Budget and portability: If your budget is under USD 1,000 and you need a lightweight grab-and-go scope, the MAK 150mm is excellent. For advanced imaging on a budget, the RASA 6 (USD 1,206) offers a strong balance. The 36 cm RASA is for professionals with a high budget and permanent setup. Check your mount's payload capacity before buying a heavy OTA.
- Field of view and speed: The RASA's f/2.2 optics allow very short sub-exposures, reducing total imaging time and often eliminating the need for autoguiding. The MAK's slower focal ratio is better for high-magnification work but requires longer exposures for faint deep-sky objects.
Product facts at a glance
- 36cm Rowe-Ackermann Schmidt Astrograph (91078): The 36 cm Rowe-Ackermann Schmidt Astrograph features a 36 cm aperture, f/2.2 optical system with a 4-element ED lens group for images free of false color, coma, and field curvature. This design delivers professional-grade, wide-field astrophotographs with very short exposure times, ideal for serious imaging projects.
36cm Rowe-Ackermann Schmidt Astrograph (91078) - MAK 150mm (6101): The iOptron MAK 150mm is a Rumak-type Maksutov-Cassegrain with multi-coated, fully-baffled optics providing apochromatic refractor-like performance at a fraction of the cost. You get high-contrast, color-free views for visual observing and planetary imaging without spending thousands on a premium refractor.
MAK 150mm (6101)
Which one fits you?
Best for
- Visual observers and planetary imagers on a budget who want a compact, high-contrast telescope
- Astrophotographers seeking a portable, ultra-fast wide-field imaging system without breaking the bank (RASA 6)
Not for
- Those who need a dedicated visual telescope with long focal length for high-magnification planetary work (choose a Maksutov-Cassegrain instead of RASA)
- Beginners on a tight budget who also want to do deep-sky astrophotography (RASA 36 cm is overkill and expensive)
