This is a new 4-lens design Apo. It has 4-lenses in the front cell (no petzval). The front pair is
oilspacest, rear pair is oilspacest and the center is airspaced. The used lightbeam was a bit tilted. Thats why you get too much light on right side and to littke on the left side. That even makes it look a bit like coma, which is not visible under real skies. When I have more time,I will shoot better images. The lens is slightly undercorrected, but with a green filter it is nearly fully corrected at the eyepiece.
The Ronchi images confirm this. The lens show a smal central zone, which is also visible on the testreport.
The testreport datas from a radial shearing interferometer at 632.8 nm say:
Strehlratio 96.9%
wavefront p.t.v. 1/6.62
wavefront RMS 1/35.7 Markus Ludes (APM-Telescopes)
Collimator : 9" F/9 Triplet Super ED TMB Apo / Ronchi 254 lines/inch |
