Fornax 105 GoTo Mount with Absolute Encoder and high performance Ritchey Chrétien 16" carbon truss tube
The Mount:
The mounts are manufactured in Hungary by experienced amateur astronomers and professional precision mechanics. The result are stable mounts with precise mechanics for astrophotography.
The mounts are now CNC machined , the worm and gear are made of bronze and stainless steel. The sensitive parts, such as worm, worm wheel and of course the motors, are sealed watertight and dustproof in the robust housing. This guarantees a long service life. The mounts can also be used well in observatories. The mounts do not react to temperature fluctuations and are practically maintenance-free.
The typical periodic error without autoguiding is very small at +/-0.5 arc seconds. It also occurs very slowly. A period is 7.5 minutes long. Any standard autoguider can guide the mount without any problems. Of course, the MC3 Goto control also offers the autoguiding interface.
"The Fornax 105 is a good mount, it has a great value for the money. It has no backlash, and reacts immediately to guiding corrections on both axes."
The MC5 GoTo controller with hand boxThe control was developed by Ursa Minor for large mounts and is ideal for Fornax mounts. Of course, the control unit is delivered readily adjusted with the mount. About 50,000 objects are already contained in the database.
- Power supply 12 V to 30 V - we recommend 24-30 Volt stabilized power supply
- Maximum current consumption 2.5 A (controller only)
- Computer connection - USB available
- Autoguiderport ST4 level available
- DSLR control (2.5 mm stereo jack) available
The Optic:
The GSO 16" f/8 Ritchey Chretien Astrograph is a dream telescope for astrophotography. The scope is perfect for observatories. The GSO 16" f/8 Ritchey Chretien Truss Tube Astrograph is a true RC telescope and will give you spectacular photo results also with large format camera sensors. The telescope is perfect for small observatories and will be carried from mounts in the EQ8 class.
The OTA comes with carbon trusses having a thermal expansion of almost zero. The OTA weight is 42kg and it has a Losmandy style dovetail rail on both sides. Lightweight yet strong carbon fibre truss tubes have low thermal expansion characteristics. Shifts in focus due to temperature changes are minimized because of this design. The trusses are also designed to flex equally, keeping the optics in collimation. The 16" f/8 RC Astrograph illuminates a max. field diameter of approx. 70mm. Without corrector, 35mm are possible. In the latter configuration, you have a pure mirror system without any lenses. You don´t need an IR cut filter and can use the full spectrum with a suitable CCD camera.
The GSO RC has a generous back focus allowing to attach many accessories like off-axis guiders, filterwheels and much more. The distance from the 2" connection of the focuser to the focus point is 306mm. To reach the perfect focus position, we suggest the GSRCV1172 and GSRCV1175 extension rings. The position of the rings is between focuser and tube backside. So you always have a good position of the draw tube.
Lightweight yet strong carbon fibre truss tubes have low thermal expansion characteristics. Shifts in focus due to temperature changes are minimized because of this design. The trusses are also designed to flex equally, keeping the optics in collimation.
The 3" Monorail focuser is a further development of the Crayford design. The load is not carried by four (often underdimensioned) ball bearings, but on a stainless steel track on the base, thus preventing tilting and bending even under high loads. It is countered by a big knurled screw that centers the inner tube exactly to the rail. The load is distributed evenly across the rail´s surface.
The hyperbolic primary and hyperbolic secondary are made from low expansion fused quartz, and finished with a scratch-resistant highly reflective 99 % dielectric coating for great contrast. The primary mirror is fixed in place in a metal mirror cell, and the secondary resides in a metal housing that can be collimated. The secondary mirror has a center mark for easy and accurate collimation. The RC telescopes has three small cooling fans in the rear cell that help create an ambient temperature within your telescope for more stable viewing and less fluctuation in focus. The fans are powered by an external battery pack. This battery holder accepts 8 AA batteries (sold separately).
Characteristics:
- Hyperbolic primary and secondary mirror for a large fully illuminated field of view
- Carbon truss tube with 2 Losmandy Level dovetail bars
- Large corrected flat field without need for additional correctors
- 99% dielectric high-reflectivity coating on main and secondary mirror for an even brighter image
- Significantly shorter cooling down time through open construction and active primary mirror ventilation
- Long back focus for correctors, reducers and also binoviewers
Delivery:
- 16" f/8 RC Astrograph with Truss Tube
- High-quality 3" MONORAIL focuser with 1:10 reduction and 2" / 1¼" adapters.
- Rear tube ventilation
- Dovetails Losmandy style on both tube sides
- Mount Fornax105
- Controller with handbox
- Absolute Encoder (2 Heidenhain ECN 125 2048 5XS08-c4 R)
- 1x20Kg counterweight & 1x10Kg counterweight
- Steel Pier
Products specifications
| Type of mount | Parallactic GOTO mount |
| Connection to eyepiece | 2" / with adapter 1 1/4" |
| Aperture | 406 mm |
| Focal ratio | f/8 |
| Mirror material | Quarz |
| Coating | 99 % dielectric |
| Focuser | 3" Monorail Focuser with 1:10 Micro Focusing |
| Tube material | Aluminium / Carbon Fibre |
| Color | white / black |
| Connections | 12V, Hand Box, RS232, Autoguider |
| Type of telescope | Ritchey Chretien with Truss Tube |
| Secondary diameter | 191 mm |
| Tube weight | 92.5 lb |
| Motors | steppermotor in both axis |
| Weight equatorial head | 50Kg |
| Payload max. (depending on using and demand) | 90 kg visual / 70 kg fotografic (excl. Counterweight) |
| Maximum slew speed | 4°/s |
| Material worm | Stainless steel K013 - 33 mm diameter |
| Power Supply | 24V DC, 3.5A |
| Color | Optik Carbon/black, Mount. black/white |
| Periodic error | +/-0.5" |
