FR | EN

Mewlon-250CRS reflector

Dall-Kirkham Mewlon series reflectors are long focal length telescopes with high F/D focal ratio.
Description

Dall-Kirkham Mewlon series reflectors are long focal length telescopes with high F/D focal ratio. The primary mirror is ellipsoidal while the secondary mirror is spherical. The surface accuracy of the optics is at least λ/20.

The CRS models incorporate a field corrector with ED glass lenses that provides a F/10 focal ratio but above all a higher corrected field than on conventional Mewlon telescope. The motorized focusing, ASCOM compatible, is done by translating the secondary mirror. The fans responsible for heating the primary mirror are managed by 3 temperature sensors located inside and outside the tube.

The Mewlon-250CRS is perfectly suited for planetary observation and imaging, due to its long focal length. It is also ideal for deep sky applications; equipped with the F/7.3 reducer it will allow the imaging of compact objects such as planetary nebulae or galaxies. The integrated 7x50 finder scope is adjustable and serves as a handle for transport.

The optical tube assembly is delivered with a pair of rings connected by a massive plate located under the tube.

Characteristics

Takahashi Mewlon-250CRS reflector

Characteristic Takahashi Mewlon-250CRS reflector
Optical design Modified Dall-Kirkham
Combination Concave elliptical primary mirror + convex spherical secondary mirror + field corrector
Diameter 250 mm
At prime focus
Focal length 2500 mm
Focal ratio F/10
Image circle diameter 40 mm
Metal Back Distance 147.9 mm
With RD CR0.73X focal reducer
Focal length 1825 mm
Focal ratio F/7.3
Image circle diameter 35 mm
Metal Back Distance 72.2 mm
With EX CR1.5X focal extender
Focal length 3780 mm
Focal ratio F/15.1
Image circle diameter 44 mm
Metal Back Distance 117.5 mm

Takahashi Mewlon-250CRS reflector

Characteristic Takahashi Mewlon-250CRS reflector
Length of the optical tube assembly 945 mm
Diameter of the optical tube assembly 280 mm
Weight 12 kg

Spot-diagram of Takahashi Mewlon-250CRS reflector at prime focus

Spot-diagram of Takahashi Mewlon-250CRS reflector with RD CR0.73X focal reducer

Documentation

System-charts

System-chart of Takahashi Mewlon-250CRS reflector Download
System-chart of Takahashi Mewlon-250CRS reflector with EX CR1.5X Download

Software

ASCOM ActiveFocuser Driver Download
INDI ActiveFocuser Driver Download

Instruction manuals

Instruction manual of Takahashi Mewlon-250CRS reflector Dowload

Available configurations

Mewlon-250CRS reflector

Reference : [TLK25400]
[TKA84420] - Tube rings 280CW
[TKA84421] - CW-plate

gallery

Lunar souther region by Dominique Dierick

NGC 4565 by Dominique Dierick

Saturn by Jean-Luc Dauvergne