TS CF-APO 90/600 mm FPL55 Triplet Apochromatic refractor

TS CF-APO 90/600 mm FPL55 Triplet Apochromat

The 90 mm apo is pure in colour and bright in light and is equally suitable for visual observation and astrophotography. Thanks to the FPL55 APO element (comparable to FPL53) the image is first-class and in practice cannot be distinguished from the world-famous LZOS lenses from Russia.

The compact apo is only slightly larger than apos with 80 mm aperture, but offers a much better performance in the sky. This refractor is an ideal traveling telescope due to the retractable dew cap and a transport length of a good 400 mm.

The objective of the 90 mm apo

The triplet lens with 90 mm aperture and 540 mm focal length fulfils the criteria of a full apo. Even at magnifications of 300x, the image is free of annoying chromatic aberrations. Even bright stars are shown on astrophotos without disturbing blue fringes.

The APO element consists of FPL55. A further special glass supports chromatic correction. The air-spaced triplet objective is fully adjustable. Each optical glass-air surface is multi-coated. The objective is in a temperature compensated, adjustable cell.

The photographic 2.5" rack&pinion focuser

The 2.5" CNC focuser is optimized for photography and can handle a load of up to 6 kg. The adjustment of the draw tube is done by gear drive. We also offer motorized focusing for the focuser. An M63x1 internal thread is available for screwed adaptations. The focuser also offers 360° rotation for selecting the correct image section.

Astrophotography with the apochromat

To achieve the optimal imaging in the field, a corrector is needed. The corrector is screwed directly to the M63 thread of the apo. We recommend two correctors, both are suitable for cameras up to full format. The working distance from the M48 thread to the sensor is 55mm.

♦ TSCFRED90 - 0.8x corrector Flattener

The corrector is specially calculated for this APO. It reduces the focal length to 432mm and improves the focal ratio to f/4.8.

♦ TSFLAT25del - 1.0x Flattener

The corrector provides maximum illumination. It does not change the focal length and focal ratio. The working distance from the M48 thread to the sensor is 55mm.

Specifications

• Aperture: 90 mm
• Focal length: 540 mm
• Focal ratio: f/6
• Objective: Multicoated APO triplet lens - FPL55
• Tube: CNC metal tube
• Limiting magnitude: 12.3 mag
• Resolution: 1.29"
• Weight tube alone: 3.54 kg
• Weight with tube rings, dovetail bar and handle: 4.6 kg
• Dew shield: retractable - can be fixed with one screw
• Focuser: 2.5" CNC focuser, 95 mm travel
• Connections on the eyepiece side: 2", 1.25" and M63x1 female thread
• Tube length (dew cap retracted): 445 mm
• Tube diameter: 105 mm
• Dew cap diameter: 121 mm