Optical Tube Sky-Watcher BKP Quattro 250/1000 OTA — reflector 250 mm aperture, 1000 mm focal length

The Sky-Watcher BKP Quattro 250/1000 OTA is an optical tube assembly engineered for wide-field deep-sky observation and astrophotography. With a 250 mm aperture and a 1000 mm focal length, the Quattro four-element astrograph design delivers a fast focal ratio suitable for capturing extended nebulae and star fields while providing sufficient resolution for planetary detail when used with a high-quality mount and camera. The OTA includes a corrector optical group that reduces coma and field curvature, producing a flat, well-corrected image plane across a large sensor area.

Advantages

The 250 mm aperture gathers substantial light for improved contrast on faint deep-sky objects, while the 1000 mm focal length and fast focal ratio enable shorter exposure times in imaging. The four-element Quattro optical layout minimizes off-axis aberrations, producing sharper stars toward the edges of the field. The OTA is compact for its aperture class, making it easier to integrate on a range of equatorial and alt-azimuth mounts. Constructed for stability and alignment, it supports both visual use and camera-mounted astrophotography with appropriate adapters.

Suitable for

Key specifications

How to use

Attach the Sky-Watcher BKP Quattro OTA to a stable equatorial or capable alt-azimuth mount that can support the tube’s mass and balance. Perform optical collimation and balance the assembly before slewing to targets. For astrophotography, mount a compatible camera using the appropriate adapter and backfocus spacing to achieve the corrected image plane; use precise guiding and polar alignment for long exposures. For visual use, fit an eyepiece or diagonal suited to the focal length and desired magnification. Use a field flattener or reducer only if specified backfocus requirements are met.

Recommendations

For best imaging results, pair the OTA with a rigid equatorial mount, a dedicated guider or off-axis guider, and a camera with a sensor size matched to the corrected field. Allow the optics to reach thermal equilibrium before critical imaging sessions and verify backfocus distance to maintain optimal correction across the field.