Alstar 1.25" 90-Degree Erecting Prism Optical - Bundle with - 1.25" 4-Elements 5X Barlow Lens

1.25" 90-degree diagonal features an image erecting prism that allows you to look into a telescope at a 90 degree angle. It produces an image that is oriented properly, which means that the image is upright and correct from left to right (i.e., a correct, non-inverted, non-reversed image).This is a great diagonal for daytime terrestrial use with small telescopes or spotting scopes. It can also be used for astronomy applications, especially when you would like to match the orientation of the star field with "correct" star maps and charts. The prism housing is made of precision molded ABS plastic and the two end barrels are precision machined from aluminum. The 1.25" nosepiece is threaded to accept standard 1.25" astronomy filters. Please Note: This diagonal can only be used with refractor telescopes and some catadioptric telescopes like Schmidt-Cassegrain, Maksutov-Cassegrain, etc. It not meant for use with Newtonian / Dobsonian reflector telescopes or other variants of Newtonian telescopes.

• With this diagonal you can match the orientation of the star field with correct star maps and charts; It produces an image that is oriented properly; which means that the image is upright but reversed left to right
• This is a great diagonal for daytime terrestrial use and night time astronomy applications for telescopes or spotting scopes
• More comfortable viewing orientation as you observe from above; filter thread for any 1.25 inch filter; Accepts standard 1.25 inch eyepieces
• The 1.25 barrel is internally threaded for use with Alstar 1.25 inch eyepiece and imaging filters; The inside of the barrel of the 5x High Power Barlow is also glare threaded to help prevent internal reflections
• The Alstar High Power 5x 4 Element Barlow Lens quintuples the power of any 1.25 inch telescope eyepiece