Product Highlights
- A breakthrough 36 cm aperture, f/2.2 optical system designed for
professional applications that require both a wide field of view and
resolution, the Rowe-Ackermann Schmidt Astrograph (RASA) 36 cm is ideal
for space surveillance and other scientific applications.
- With a 4-element lens group featuring extra-low dispersion (ED)
glass for images free of false color, coma, and field curvature, RASA 36
cm is also an excellent choice for advanced astroimaging.
-
New Ultra-Stable Focus System (USFS) minimizes focus shift, mirror flop, and any other unwanted motion of the primary mirror, enabling easy and dependable focus.
- 60 mm optimized image circle maintains pinpoint stars to the far corners of the largest available sensors.
- An extended spectral range takes advantage of sensor response in the
700-900 nm range, allowing a brighter overall signal to be detected.
The Rowe-Ackermann Schmidt Astrograph (RASA) V2 is a cost-effective optical system for space surveillance, Space Situational Awareness (SSA),
other scientific applications, and advanced wide-field astroimaging. It
offers unprecedented value in aperture, speed, field of view, and
optical performance. The RASA design has a convenient external
prime-focus image capture location with a flat focal plane, providing
small spot sizes to the edge of a wide field. Images are free of optical
defects like field curvature, off-axis coma, and astigmatism.
Optical Performance
The 36 cm aperture version is the largest RASA Celestron
manufactures; it is the biggest and fastest (f/2.2) optical instrument
of its kind available off-the-shelf. Unlike most telescopes, which only
focus visible light (400-700 nm), the RASA 36 cm focuses an extended
spectral range (400-900 nm), allowing a brighter signal to be detected
by a camera sensor.
Advanced Features
RASA 36 V2 features the new Ultra-Stable Focus System (USFS). At the
heart of this system is a precision linear ball bearing. The bearing
minimizes focus shift (unwanted lateral movement of the primary mirror
during focusing, which causes shifting of the image) and mirror flop
(movement of the primary mirror when the telescope is pointing to
different positions in the sky). The USFS is compatible with the
optional Celestron Focus Motor (#94155-A). The integrated 12V DC MagLev
fan reduces cooldown time and provides optimal airflow through the
dust-filtered optical tube. RASA 36 cm's ample back-focus distance (77.5
mm) accommodates a wide variety of imaging sensors. You may add a
custom camera adapter for a field of view up to 4.4 degrees.
Additional Features
- Celestron's proprietary XLT coatings, consisting of
high-transmission multi-coatings for lenses and high-reflectivity
aluminum coatings, ensure good light throughput for the optical system.
- Integrated cooling fan helps optics cool down to ambient temperature
and pulls air through vents with micromesh to prevent dust ingress.
- Dual dovetail bars offer flexibility to mount the optical tube and
conveniently attach additional accessories. Accommodates CGE/Losmandy
style dovetails.
- Two sets of 2x threaded insert holes in the rear cell provide additional mounting options
- Move and mount your optical tube with ease with carrying handles on the rear cell.
- Although not normally needed, there are 3x sets of push-pull screws
to adjust the lens group to achieve optical alignment for the entire
system.
- Includes M48 camera adapter
Important freight requirement RASA 36 cm is a
professional-caliber, high-precision instrument. Our technicians
manufacture and align each RASA 36 cm to an exacting standard to provide
exceptional optical performance. We package the telescope to ensure it
retains alignment and performance during transport. However, due to the
weight, size, and known stresses of shipping via parcel service,
Celestron has determined that the ideal transport is a palletized
delivery via LTL truck freight. For all domestic deliveries, Celestron
will ship via this method. We also require this shipping method for all deliveries from Celestron dealers to end customers.
Optical Tube Info:
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Optical Design:
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Rowe-Ackermann Schmidt Astrograph
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Aperture:
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355.6mm (14")
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Focal Length:
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790mm (31.1")
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Focal Ratio:
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f/2.2
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Central obstruction diameter:
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158mm (6.22")(44% of aperture diameter)
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Light Gathering Power (Compared to human eye):
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2581X
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Resolution (Rayleigh):
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0.39 arc seconds
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Resolution (Dawes):
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0.36 arc seconds
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Image circle:
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60.1mm (2.36") Ø, 4.4°
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Useable field:
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70mm (2.75") Ø, 5.1°, only minimal performance loss at edge of FOV
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Wavelength range:
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400 – 900 nm
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Spot size:
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< 6.3 µm RMS across FOV
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Optical coatings:
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Enhanced aluminum, XLT Multi-Coated throughout
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Off-axis Illumination:
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83% at 30mm (1.18") off-axis
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Optical window:
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104mm (4.09") Ø
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Back focus with included camera adapter:
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55mm (2.16")
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Back focus from top of threaded collar:
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77.5mm (3.05")
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Optical Tube:
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Aluminum
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Optical Tube Length:
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1079.5mm (42.5")
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Optical Tube Diameter:
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406.4mm (16")
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Focuser:
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Ultra-Stable Focus System (USFS), minimizes lateral movement of primary mirror
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Finderscope:
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Not included
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Optical Tube Weight:
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75 lbs (34.02 kg)
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Other features:
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Ventilation fan, dual dovetail mounting bars
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Included Items:
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48mm (1.89") camera adapter Fan battery pack
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Solar Warning | - Never
look directly at the Sun with the naked eye or with an optic (unless
you have the proper solar filter). Permanent and irreversible eye damage
may result.
- Never use your optic to project an image of the Sun
onto any surface. Internal heat build-up can damage the optic and any
accessories attached to it.
- Never leave your optic unsupervised.
Make sure an adult who is familiar with the correct operating
procedures is with your optic at all times, especially when children are
present.
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FAQ
Q:
What is the heaviest recommend load for mounting a camera onto the RASA 36cm?
A:
We recommend a load of no more than 38 lbs. at 5.6 inches away from the 14" Schmidt corrector.
Q:
Is there any preferred way of focusing my RASA 36cm to ensure sharpest stars at the edges of a large sensor?
A:
Final focusing of the RASA 36cm should always
be done by rotating the focus knob counter-clockwise (CCW). This
direction of focus opposes the pull of gravity on the primary mirror,
which provides the most stable focus. This also places the primary
mirror in the optimal position for best optical performance at F/2.2 and
provides best star images at the very edge of the huge 60mm image
circle.