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CCA-250 reflector OTA

Description

The CCA-250 (Corrected Cassegrain Astrograph) is a flat field telescope dedicated to deep sky astrophotography with an 88mm image circle. It allows the use of 3 different focal lengths by adding optional reducers and extenders. In addition to the standard F/5 focal ratio at the primary focus, it is possible to switch to F/3.6 using either one of the 2 reducers or to F/7.5 using one of the 2 extenders. The choice will depend on the desired image circle and the size of the camera sensor or photo housing used.

Motorised focusing, ASCOM compatible, is done by translating the secondary mirror. The fans responsible for cooling the primary mirror are managed by 3 temperature sensors distributed inside and outside the carbon tube. The telescope is delivered with a 7x50 finder and Losmandy type male and female dovetails.

With the CCA-250 telescope, Takahashi has created an extremely versatile astrograph with a top-of-the-range finish, irreproachable optical and mechanical quality and a magnificent design combining aluminium and carbon.

Characteristics
Optical specifications
Optical design Modified Cassegrain
Combination Concave parabolic primary mirror + convex spherical secondary mirror + corrector
Diameter 250 mm
At prime focus
Focal length 1250 mm
Focal ratio F/5
Image circle diameter 88 mm
Metal Back Distance 193.9 mm
With RD CR0.73X focal reducer
Focal length 910 mm
Focal ratio F/3.6
Image circle diameter 38 mm
Metal Back Distance 56.2 mm
With 645RD CA0.72X focal reducer
Focal length 890 mm
Focal ratio F/3.6
Image circle diameter 60 mm
Metal Back Distance 56.2 mm
With EX CR1.5X Extender
Focal length 1880 mm
Focal ratio F/D 7,5
Image circle diameter 40 mm
Metal Back Distance 117.5 mm
Mechanical specifications
Length of the optical tube assembly 870 mm
Diameter of the optical tube assembly 80 mm
Weight 1.4 kg
Focuser type Motorized motion of the secondary mirror

Spot-diagram of the Takahashi CCA-250 reflector at prime focus

Spot-diagram of the Takahashi CCA-250 reflector with reducer RD CR0.73X

Spot-diagram of the Takahashi CCA-250 reflector with reducer 645RD CA0.72X

Spot-diagram of the Takahashi CCA-250 reflector with extender EX CR1.5X

Documentation

System-charts

Main system-chart of the Takahashi CCA-250 reflector Télécharger
System-chart of the Takahashi CCA-250 reflector with reducers Télécharger

Instruction manual

Instruction manual of the Takahashi CCA-250 reflector Télécharger

Available configurations

CCA-250 reflector OTA

Reference : [TCK25010]
[TKP75422] - Female dovetail saddle for CCA-250