ASKAR 151PHQ APO QUADRUPLET f/7
Askar
Apochromatic Petzval quadruplet
13.7 kg
ASKAR 151PHQ APO QUADRUPLET f/7 is backordered and will ship as soon as it is back in stock.
The Askar 151PHQ is a professional apochromatic flatfield Petzval quadruplet with a focal ratio of f/7 and a corrected field of 60mm in diameter, making it suitable for use with medium-format cameras.
The largest of the Askar refractors so far, the 151PHQ includes two Extra Low Dispersion glass elements for superb correction of chromatic aberration. The central RMS radius is less than 2 microns, with sharp stars all the way to the edge of the field.
Differently from standard ED refractors, the Askar 151PHQ features a Petzval design that does not require to set the sensor to a specific distance to the last lens. That leaves the freedom to use any filter wheel, any off-axis guider or accessory without any worry to calculate the correct distance from the flattener.
With a large 60mm image circle and a focal ratio of f/7, this is the perfect astrograph for the advanced astrophotographer. The large rack and pinion 3.4" focuser has a massive 8kg payload capacity, can be rotated 360° to perfectly frame the subject and it has a reduction gear of 10:1 for precise focusing. Its long travel distance allows use as a visual instrument as well as a capable astrograph. The 151PHQ is natively compatible with the Prima Luce Lab Sesto Senso 2 robotic microfocuser.
All the lenses are fully multi-coated and the tube is internally flocked to reduce reflections and absorb stray light. The tube is made of CNC-machined aluminium, the rack and pinion focusing mechanism of brass and the mechanical components are engineered to provide the best rigidity, performance and durability.
The Askar 151PHQ comes with a variety of adapters to connect a wide range of imaging and visual accessories. An additional 0.7x 3" reducer transforms it into a fast f/4.9 astrograph with a focal length of 740mm.
Specifications
Optical design | Apochromatic Quadruplet air-spaced |
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Objective diameter | 151 mm |
Focal length | 1057 mm |
Focal ratio | f/7 |
Resolving power | 0.91 arc seconds |
Stellar limiting magnitude | 13.59 |
Max. magnification | 377.5 x |
Light gathering power | 465.33 times the human eye |
Mount attachment | Losmandy style dovetail plate (300 mm long) |
Focuser | Rack & pinion dual speed (10:1) 3.4" diameter |
Included connection adapters | M86 x 1, M68 x 1, M54 x 0.75, M48 x 0.75, 2" |
Backfocus | 78 mm maximum (from the base of the M48 thread) |
Tube weight | 13.7 kg (including tube rings and dovetail bar) |
Tube diameter | 163 mm |
Dew shield diameter | 180 mm |
SKU | AS-150PHQ |
Included items
- Askar 151PHQ
- Pair of tube rings
- 300mm Losmandy style dovetail bar
- Carrying handle
- Adapter M86 x 1 to M68 x 1
- Adapter M68 x 1 to M54 x 0.75
- Adapter M54 x 0.75 to M54 x 0.75
- Adapter M54 x 0.75 to M48 x 0.75 with 2" filter thread
- 2" visual back
- 1.25" adapter
- Manual
Gallery
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Optical design
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Aperture
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Focal length
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Focal ratio
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Weight