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JTW Dall Kirkham 400mm f5.5
£18,179.00 inc. tax

£15,149.17 ex. tax
? Tax based on United Kingdom.


JTW Astronomy Dall Kirkham 250mm f5.5

The Enhanced Corrected Dall-Kirkham (ECDK) telescope is our workhorse. This is the most economical route to a high performance telescope, often the performance of an RC is not needed, ECDKs are easier to manufacture and therefore are very cost effective. The tube assembly is semi-ruggedised and is of fail-safe construction.

The mirror supports in instruments under 600 mm are high precision floatation cells with full edge supports, larger mirrors are supported with kinematic face and edge supports. The focuser is included as standard, this is achieved by moving the secondary mirror. The ECDK includes a 2 element corrector with optional 3-element system and integrated ADC.


Aperture (mm) 400
Recommended mount type GEM
Tube tube Truss
Focal length (mm) 2200
OTA Weight (kg) 41
Back focus 200
Focal ratio F/ 5.5
Fully corrected imaging circle (mm) 45
Cooling fans Primary and secondary mirror
Airflow Laminar flow & Rear
Mirror coatings Enhanced Aluminium + SiO2 protective layer
Focuser Integrated JTW Rhino
Clear aperture (mm) 75
Tube construction Carbon fiber & Aluminium
Truss construction Pre-loaded carbon fiber
Optical surface quality (Strehl, PTV) 0.97, 1/10
Primary mirror substrate Schott Supremax 33
Primary mirror cell 18 point floatation cell
Primary mirror edge support 6 point athermalised
Primary baffle Skeletal baffles
Secondary mirror substrate Schott Supremax 33
Secondary mirror cell 3 point floatation cell
Secondary baffle Skeletal baffles
Bolting A4 Stainless steel
Metal protection Dual
Surface treatment Aluminium – 20 micron hard-coat anodising
Paint Exterior grade powdercoat (environmentally friendly)
Anti dew system Included


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Product Code
- JTW-DallK
Product Condition
- New


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    11 Drift Road, Clanfield, Waterlooville, Hampshire, PO80JJ, United Kingdom
    +44 23 9257 0283
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