The 55mm focal length has the largest true field possible for 2" eyepiece holders - 3x the true field of any 1.25" eyepiece. The focal plane is placed at the end of the barrel to minimize vignetting. Performance with Schmidt-Cassegrains is remarkable since it avoids the image degradation and severe vignetting which occurs when using tele-compressors. Long eye-relief and a unique adjustable eyeguard make it easy to use for spectacle wearers.
Since Televue introduced their Plossls in 1980, they have won praise and patents. Televue Plossls, designed by Al Nagler, have been a recognized benchmark of performance and value in the class of 50° apparent FOV eyepieces. While the Plossl may be the least expensive Televue eyepieces, they still enjoy the same care and attention to detail as Televeu's more exotic eyepieces.
Diffraction limiited "on-axis" performance is a given. Using more expensive high index glasses to reduce astigmatism and lateral colour at the fields edge, Televue Plossls deliver sharper images than any other brand of 4 or 5 element Plossl or Orthoscopic design. The faster the focal ratio of your telescope, the greater your visual reward for using Televue eyepieces. Televue Plossls feature full multi-coatings for greatest light transmission and contrast. Blackened lens edges and internal anit-reflection threads tweak the last bit of contrast for maximum image detail. The sharper field focusers star light into perceptible points ans allows those with undriven mounts to gaze longer before repositioning the image.
For a bit more than generic brands, you can own a genuine Televue Plossl!
55mm Focal Length
2" Barrel Size
50° Apparent Field of View
38mm Eye Relief
46mm Field Stop