Dobsonian telescope Skywatcher 10" Pyrex 254/1200 aperture 254 mm focal length 1200 mm

Skywatcher Dobsonian 10" Pyrex (aperture 254 mm, focal length 1200 mm) is a Newtonian reflector on a Dobsonian alt-azimuth mount designed for visual astronomy. The 254 mm Pyrex primary mirror gathers substantial light for bright, high-contrast views of the Moon, planets and many deep-sky objects. With a 1200 mm focal length and classic Dobsonian rocker box, the instrument provides a straightforward, stable platform for manual pointing and smooth intuitive tracking during observing sessions.

Advantages

The large Pyrex primary mirror offers improved thermal stability and sustained optical performance during temperature changes, reducing image degradation caused by mirror deformation. The Dobsonian mount provides a low center of gravity and simple, tool-free setup, making the telescope ready for use quickly. The combination of a fast focal ratio and large aperture yields bright views of extended nebulae and clear planetary detail under suitable seeing conditions. The optical design and mechanical simplicity make maintenance and collimation accessible to amateur users.

Suitable for

• Visual observation of the Moon and planets
• Wide-field views of star clusters and bright nebulae
• Amateur deep-sky observing sessions from suburban or rural locations
• Educational demonstrations and backyard astronomy

Key specifications

• Aperture: 254 mm Pyrex primary mirror
• Focal length: 1200 mm
• Optical design: Newtonian reflector
• Mount type: Dobsonian alt-azimuth rocker box
• Focal ratio: f/4.7 (approximate)
• Suitable for visual observing; eyepieces and accessories sold separately

How to use

Assemble the rocker box and optical tube according to the included instructions, ensuring the primary mirror cell and secondary mirror are secure. Begin observations by balancing the tube on the Dobsonian mount and installing a suitable eyepiece. Use the mount's friction or altitude adjustment and the azimuth rotation to point at targets; manual nudges allow continuous tracking. Before each session check collimation using a collimation tool or star test and allow the telescope to reach thermal equilibrium outdoors for best image quality.

Usage recommendations

For best results start with low- to medium-power eyepieces to locate targets, then increase magnification for planetary detail. Allow at least 30–60 minutes for the Pyrex mirror to acclimate to outdoor temperature. Use a simple star diagonal or correct image diagonal for comfortable viewing, and perform periodic collimation checks. Transport in a padded case and protect mirrors from dew using a cover or dew heater if observing in humid conditions.