BS 250 FC/Ti: Baker-Schmidt Astrograph 250 mm f/2,8 Full Carbon/Titanium
250 mm F/2.8 ultra Hi End Baker-Schmidt truss Astrograph.
The Baker Schmidt "camera" is a special type of Schmidt Cassegrain telescope designed for the wide field and fast astrophotography. We optimized this system in order to be mechanically very precise and stable, and therefore guarantee an unsurpassed imaging quality and ease of use.
It sports 2 spherical mirrors and a Schmidt corrector. The system is flat-field and delivers an image absolutely free of coma, astigmatism and color aberration on a field of 50 mm. The real beauty of this optical prescription is its simplicity and elegance: in fact with only one refractive element, and without further correction we can deliver an instrument with outstanding performance at a great price.
Due to the limited backfocus, typical of all astrographs, the focusing system will be installed on the secondary mirror assembly. A high precision linear actuator with linear resolution of ca. 0,6 µ, will take care of a smooth and backlash free focusing.
Because of the very high speed of the instrument, the focal plane will be fully adjustable with micrometric precision. It will host a M100x1 threaded ring ready to receive all kind of desired adapters.
The truss frame is entirely built with mono directional high module carbon fiber tubes. The connection rings are fabricated with 6 mm high module carbon fiber plates cut with water-jet.The optics will be intubated in a very thin carbon fiber enclosure to prevent stray light and dew.
The primary mirror cell is a true technological jewel: 100% structural carbon fiber construction, 9 points computer optimized mechanical cushion, and zero thermal expansion. It is fully tiltable through 3 titanium bolts placed on the telescope's back plane. The cell's maximum deformations under the highest mechanical stress configuration (tube pointing at the zenith) are less than 0.03 mm. This value still improves with the optional Carbon/Titanium back plane.
With the secondary mirror assembly we created a mechanism of unmatched reliability, stability and lightness. The fully tiltable cell is fixed on a 16 mm rectified titanium bar, firmly held in position by a high precision axial linear ball bearing.
The dovetails are engineered with a Knaeble proprietary hybrid Aluminium-Carbon fiber construction (optional Titanium/Carbon). This type of design minimizes torsion deformation and structural misalignment under every pointing orientation. In comparison with traditional CNC aluminium dovetails, the deformations are reduced by a factor 40.
- Optics f/2,8 Baker-Schmidt made in Italy
- Optical quality: Strehl ratio >95%
- Opening 250 mm
- Focal length 700 mm
- Pyrex optical set.
- Diameter Non Vignetted-field: 50 mm
- Primary focal plane distance: 150 mm
- Total mass (including dovetails): ca. 15 kg.
- Overall length: ca. 1.000 mm
- Entirely designed and constructed in virtual environment with Catia V5.
- All CNC parts programmed in CAM directly in Catia V5.
- FEM mechanical, modal and thermal simulations are performed with Ansys Workbench on every component as well as on the complete assembly with linear and nonlinear methods.
- Proprietary 9 points computer optimized Full-Carbon-Fiber primary mirror cell.
- 8 mm thick solid carbon fiber CNC backplane.
- Optional composite Carbon-fiber/Titanium backplane construction.
- Proprietary Zero expansion Full-Carbon-Fiber/Titanium truss construction.
- Proprietary highly accurate M1 and M2 tilting mechanisms.
- Motorized fosusing system via high precision linear actuator
- Proprietary "Hollow Technology" hybrid CNC Aluminum/Carbon-fiber (3" Losmandy compatible) dovetail plates.
- Active cooling.
- Completely made in (Berlin) Germany from German made components.
- Shipping case included