Skywatcher Maksutov-Cassegrain Optical Tube BKMAK 150 OTAW 150 mm aperture

Skywatcher Maksutov-Cassegrain Optical Tube BKMAK 150 OTAW is a 150 mm aperture optical tube assembly designed for compact, high-contrast observation of planets and select deep-sky objects. The Maksutov‑Cassegrain optical layout provides a long effective focal length in a short, portable tube, delivering sharp images with reduced chromatic aberration. As an OTA, it contains the primary optical components but does not include a mount, tripod, or accessory kit; it is intended for users who already have or plan to choose a compatible mount and imaging equipment.

Advantages

The BKMAK 150 OTAW offers a compact form factor with a long focal ratio suitable for high magnification views, making it efficient for planetary, lunar, and double-star observing. The closed-tube Maksutov design keeps optics protected from dust and reduces the need for frequent collimation. Its 150 mm aperture balances light-gathering power and portability, while the optical configuration minimizes chromatic and off-axis aberrations for crisp, high-contrast images.

Suitable for

• Planetary and lunar observation at high magnifications
• Imaging of planets and bright deep-sky targets when used on a stable equatorial or alt-azimuth mount
• Portable field astronomy where compact size and robust optics are preferred
• Observers who already own a compatible mount and accessories

Key specifications

• Aperture: 150 mm
• Optical design: Maksutov‑Cassegrain
• Configuration: Optical Tube Assembly (OTA) — no mount or tripod included
• Intended use: Visual observation and astrophotography with compatible mounts
• Tube type: Closed-tube design to reduce dust and thermal currents
• Typical strengths: Long effective focal length in a compact tube, reduced chromatic aberration, high-contrast imaging

How to use

Install the BKMAK 150 OTAW on a stable, appropriately rated mount using the provided mounting rail or tube rings compatible with the optical tube diameter. Balance the setup on the mount before attaching accessories. For visual observing, fit an eyepiece in the focuser and adjust focus while pointing at a bright object; start with lower magnification to locate the target, then increase magnification as seeing permits. For astrophotography, attach a suitable camera with the correct adapters, ensure the mount is polar-aligned (for long exposures) or accurately tracked, and use focus aids and live view to achieve precise focus. Allow the tube to reach thermal equilibrium with ambient temperature for best image quality.

Usage recommendations

Use the BKMAK 150 OTAW on a rigid mount with sufficient payload capacity and precise tracking for astrophotography. Allow time for thermal acclimation, and use high-quality eyepieces or imaging adapters to match the telescope’s focal ratio. Regularly check and secure mounting hardware; store the closed tube in a dry environment when not in use to protect the optics.