Telescope Skywatcher optical tube BKP 250mm aperture 1200mm focal length

Skywatcher optical tube BKP with 250 mm aperture and 1200 mm focal length is a Newtonian-type reflecting OTA intended as the optical core for a high-aperture amateur or semi-professional telescope. The 250 mm primary mirror delivers significant light-gathering ability while the 1200 mm focal length produces a moderate focal ratio that balances wide-field deep-sky imaging and higher-magnification planetary observing. The tube is supplied as an OTA only; mount, eyepieces, focuser accessories and finder scopes are not included.

Advantages

The Skywatcher BKP optical tube offers a large aperture for improved limiting magnitude and resolved detail compared with smaller instruments. Its 1200 mm focal length provides a practical compromise between field of view and image scale, which is suitable for a broad range of targets from nebulae and galaxies to planets and lunar detail. The construction is focused on optical performance and mechanical stability to support visual use and astrophotography when paired with an appropriate mount and accessories.

Suitable for

• Visual observation of deep-sky objects (nebulae, star clusters, galaxies)
• Planetary and lunar observing at moderate to high magnifications
• Astrophotography with a stable equatorial or alt-azimuth mount and guiding
• Telescope upgrades for experienced amateurs and small observatories

Key specifications

• Aperture: 250 mm
• Focal length: 1200 mm
• Optical design: Newtonian reflector (open tube OTA)
• Focal ratio: f/4.8 (approximate)
• Primary mirror type: parabolic reflecting mirror
• Typical use: visual observing and astrophotography when mounted

How to use

Install the optical tube on a compatible mount rated for the instrument's weight and moment; an equatorial mount with sufficient payload and tracking capability is recommended for long-exposure astrophotography. Balance the tube carefully, attach a suitable focuser, and collimate the primary and secondary mirrors before observing. Fit eyepieces, cameras or a diagonal as required for the intended observing mode, and perform fine focusing and alignment using a star or artificial target.

Usage recommendations

For best results, pair the BKP 250mm optical tube with a rigid mount and, for imaging, an autoguider or off-axis guider. Regular collimation and periodic mirror cleaning in a dust-free environment will maintain optical performance. Choose eyepieces and barlow lenses that match the focal ratio to achieve the desired field of view and image scale.