Understanding Focal Reducers

Understanding Focal Reducers

A focal reducer, sometimes called a Shapley lens, does exactly what its name promises: it shortens a telescope’s effective focal length. In that sense, it is the optical opposite of...

Understanding Focal Reducers

A focal reducer, sometimes called a Shapley lens, does exactly what its name promises: it shortens a telescope’s effective focal length. In that sense, it is the optical opposite of...

Back Focus for Astrophotography: How to Get Perfect Spacing

Back Focus for Astrophotography: How to Get Perfect Spacing

Most full-frame and APS-C DSLR and mirrorless cameras have an industry-standard 55 mm of internal back focus when paired with a lens or a T-ring. The thickness of the T-ring...

Back Focus for Astrophotography: How to Get Perfect Spacing

Most full-frame and APS-C DSLR and mirrorless cameras have an industry-standard 55 mm of internal back focus when paired with a lens or a T-ring. The thickness of the T-ring...

Understanding Your Telescope’s Back Focus

Understanding Your Telescope’s Back Focus

Back focus is the distance from the end of your focuser’s drawtube to the point where your telescope forms an image—the focal plane. When your telescope is used in its...

Understanding Your Telescope’s Back Focus

Back focus is the distance from the end of your focuser’s drawtube to the point where your telescope forms an image—the focal plane. When your telescope is used in its...

Fall Constellation Spotlight: Cetus, the Sea Monster

Fall Constellation Spotlight: Cetus, the Sea Monster

As Autumn deepens and the nights grow longer, stargazers across the Northern Hemisphere turn their gaze southward to witness the rise of Cetus, the Sea Monster. This sprawling constellation stretch...

Fall Constellation Spotlight: Cetus, the Sea Monster

As Autumn deepens and the nights grow longer, stargazers across the Northern Hemisphere turn their gaze southward to witness the rise of Cetus, the Sea Monster. This sprawling constellation stretch...

Fall Constellation Spotlight: Cassiopeia

Fall Constellation Spotlight: Cassiopeia

🍂 As Fall settles in, the night sky transforms—bringing crisp air, longer evenings, and a fresh array of constellations to explore. Among the most striking constellations in the Northern Hemisphere...

Fall Constellation Spotlight: Cassiopeia

🍂 As Fall settles in, the night sky transforms—bringing crisp air, longer evenings, and a fresh array of constellations to explore. Among the most striking constellations in the Northern Hemisphere...

All About Barlow Lenses

All About Barlow Lenses

Every novice telescope user has seen advertisements describing how a Barlow lens increases an eyepiece’s magnification and expands the power of a telescope. Many astronomy beginners are confused ab...

All About Barlow Lenses

Every novice telescope user has seen advertisements describing how a Barlow lens increases an eyepiece’s magnification and expands the power of a telescope. Many astronomy beginners are confused ab...