Baader Telecentric system TZ 3

Telecentric with a generously dimensioned entrance aperture with negative lens group, with 2" (50.8mm) threads on both sides - incl. T-2 adapter and 2" i/a reversing ring included in the standard scope of delivery ; 46mm free aperture at the connection to the H-alpha filter, thus also suitable for SolarSpectrum Research Grade filters ; Extra long working distance of 250 mm for optimized focal length reduction with telecompressors or for binocular observation ; Aplanatic, with 3x focal length extension and free of field curvature - provides f/30 on telescopes with f/10 ; Specially calculated and manufactured for the H-alpha wavelength, with 99% Strehl (99% definition brightness at 656.3 nm) depending on the telescope system used ; Even at Calcium-K (396nm) it still provides diffraction-limited imaging with approx. 80% Strehl