“This is a triplet Super-ED Apochromat , airspaced and fully multicoated.
The starimages show no false color at all. The inner fresnel rings show a very minor difference due the a minimal amount of chromatic aberration. The outer rings are equal and show an extremely smooth lens which is confirmed by the interferometrical testresults above. This lens is made near to the theoretical and practical limits”
Markus Ludes (APM-Telescopes)