In our Astrographs, it is introduced a further refractive element correction (in ED glass) – this 3th lens introduction was done by Leonardo Priami in late 2010 as described in its web site LINK-, reaching extremely wide true diffraction limited corrected field (over 80 mm in diameter for the TI45 f/4) without introduce color aberrations (from 400 nm to 1,6 micron of wavelength). These performances of very fast and very corrected optics allows to this optics to be used with success both in narrow band filter imaging and in Near Infrared imaging. This optical configuration -called here Modified Harmer Wynne– is used now for ALL our Astrographs.
Our faster astrographs, TI55 f/2,6 and TI65 f/2,6 represent a further primacy on the market being the astrographs with greater diameter and higher luminosity on the market of semi-professional instruments. And thanks to the lightened mirrors they can be supported by commercial mounts. They use a custom designed 6″ Wynne corrector (TI-160 Wynne corrector).
Only the “slower” astrographs, TI45 f/8, (now available only on request) we use a Corrected Cassegrain system with two element corrector that deliver awesome performances.