TS-Optics 110 mm f/4.8 Flatfield APO refractor with FDC100 triplet lens

An ultimate and compact APO refractor for astrophotography and observation.

♦ Aperture 110 mm / focal length 528 mm / focal ratio f/4.8

♦ FDD100 triplet lens with f/6 - color correction comparable to FPL53 triplet

♦ 4-element 0.8x corrector with M48 camera connection and working distance of 55 mm included - calculated for this lens for maximum field sharpness

♦ 2" filter insert thread and 360° rotation included

♦ 2" Visual-Back can be screwed to the focuser instead of the corrector for observation - working distance suitable for 1.25" and 2" accessories

♦ Delivered in a high-quality transport case

♦ Each apo is tested before shipping (cosmetics, optics and mechanics), the optics are collimated.
TS 110mm f/4.8 flatfield apo for astrophotography
This pure color apochromat offers very well chromatically corrected optics and the best possible field correction. The lens is optimized for very good color correction without compromise. The sphere is also exemplary. The Ronchi test reveals straight lines. The Apo is therefore designed for observation up to the highest magnification range of around 350x.

For astrophotography, a 0.8x full-frame corrector was developed specifically for this lens. The 4-element corrector offers very good image quality across the entire field. Even with high-resolution full-format sensors, such as. B. with the ASI6200 camera from ZWO, the stars will remain point-like at the edge.

The idea behind the TSAPO110FLAT:

Until now, flatfield optics have always had to make a compromise: you sacrifice some on-axis sharpness in favor of good field sharpness. Or you can use a “general corrector” and try to achieve the best possible field correction by adapting distances. The result is a compromise, usually a good one, but a compromise.

The concept behind this apo avoids compromise, as the 110mm f/6 lens is optimized for maximum on-axis sharpness. And the corrector is optimized only for this lens. Four lenses were necessary in order to provide the high level of sharpness across the entire field.
Opening: 110mm
Lens: FCD100 Triplet - aperture ratio f/6
Collimation: Through 3x pull and pressure screws on the front of the lens
Photographic aperture ratio: f/4.8 with the 4-element corrector
Focuser: 3.2" CNC focuser
Camera connection: M48x0.75 with 2" filter thread
Working distance: 55 mm from the M48 thread
Visual ports: 2" and 1.25"
Visual working distance: 125 mm from 2" - suitable for 2" accessories
Adjustment range of the focuser: 100 mm
Dew cap diameter: 155 mm