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Details
Astro-Physics 0,80x Focal Reducer/CCD Telecompressor
The 92 Stowaway’s Telecompressor Corrector is used to provide 0.80x image reduction while correcting the field curvature that is inherent in all refracting telescopes. It will provide pin point stars to the very corners of an APS-C camera sensor. It has a corrected image circle of approximately 40 mm.
Requires a 2,5"- DoveLoc-Adapter That comes with the 92mm f/6.65 Stowaway. The system is also compatible with the older Astro Physics 105mm EDT Traveler (the specifications are for the 92mm Stowaway, not for the Traveler). If you are using a Traveler, you will also need to purchase the 2.5" DoveLoc End Cap for AP 2.7" Focusers ( EC2725)
To make your imaging convenient and precise Astro-Physics has incorporated a circular dovetail system into our modern flatteners and TCCs that Astro-Physics call the “DoveLoc”. Three uniquely machined thumbscrews pull the flattener or TCC into a tight and secure lock that makes the optics perfectly orthogonal. What adds to the convenience of the DoveLoc is that loosening the thumbscrews allows your camera to be safely rotated for image composition.
Astro-Physics produces adapters for the popular Canon EOS and Nikon DSLR cameras (DSLR25EOS & DSLR25NIK). If you have another DSLR camera or CCD camera system, then we recommend having a custom adapter made through Precise Parts. The Build-An-Adapter tool has the information that you need and is easy to use.
The Astro-Physics 92mm f6.65 Stowaway (#1400092 , € 5275,-) uses a very robust 2.5” focuser, however we caution against hanging a large and heavy CCD camera from the optical train. It is a small scope and meant to be portable and fun!
Machined aluminum covers are included.
If you are using a Traveler, you will also need to purchase the 2.5" DoveLoc End Cap for AP 2.7" Focusers.
The technical data of image field flattening and Focal Reducer
Photographic field with dedicated Field Flattener - Unvignetted image circle: 50 mm diameter
- 35 mm format: 3.2 x 2.2 degrees
- Focal ratio: f/7
- Focal length: 644 mm
- Backfocus Spacing: 2.52" (64.1 mm)
Photographic field with 0.8x Telecompressor Corrector - Unvignetted image circle: 40 mm diameter
- 35 mm format: 4.2 x 2.9 degrees
- Focal ratio: f/5.3
- Focal length: 488 mm
- Backfocus Spacing: 2.52" (64.1 mm)
Photographic field with 2x Barlow - Image circle: 32 mm diameter, 1.2 degrees
- Covers APS format
- Focal ratio: f/13 @ 90 mm backfocus
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The camera at the eyepiece
Pitfalls and opportunities In this article we want to show the different ways to enlarge the image or to take pictures through the eyepiece quickly and easily with a camera. These techniques are interesting for photographing the moon and planets as well as for anyone who wants to photograph through an eyepiece - for example, for nature photography through a spotting scope. "Getting closer" is the goal of many photographers. In other words, the longest possible focal length to image the objects as large as possible on the sensor. A practical rule of thumb for astronomers is that the sun and moon appear on the sensor approximately with a diameter of just under one centimeter per meter of focal length. Since long focal length telescopes quickly become very unwieldy or at least require a very heavy mount, it is difficult - especially as an amateur - to reach for the largest possible telescope. A 14" Schmidt-Cassegrain with 3900 mm focal length, as it can be found on many observatories, is for most people the longest focal length telescope, which they can access at least through a club membership. So how do you get closer? The answer is simple: a magnifying...
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Eyepiece Projection - How good can it get?
Question: With eyepiece projection, the image at the edge is extremely blurred. What could be the reason for this? For eyepiece projection with our Morpheus and Hyperion (zoom) eyepieces, we recommend a distance between eyepiece and T-ring of 40 mm on full-frame cameras, in addition to the 55 mm that were the flange focal distance of all "SLR" and DSLR camera bodies for decades when a T-ring was placed in front. Only with a T-ring that maintains this distance can old lenses with a T-thread deliver sharp images. Therefore, it has been tried to take this distance into account in all designs, because this is the only way to ensure that the sharpness performance is optimal. Of course, all this is only valid to a limited extent today - because the DSLR standard is losing it importance and the term „T-ring“ is all too often reduced to the mechanical thread and not the correct distances. In our brochure on digiscopy, we have therefore stated the back focal distance of 55mm. With a DSLR (full frame or APS-C), this distance is also maintained in good approximation with modern, narrow T-rings, which are intended for use on telescopes, where every millimetre often...
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Astro-Physics – High-end German Equatorial Mounts
HIGH-QUALITY PROFESSIONAL ASTRONOMICAL MOUNTS Keeping to the same quality standards that have made the fully-apochromatic refractors legendary, Roland Christen's company has been building German Equatorial GoTo mounts for more than three decades. Their proven stability, accuracy and durability is the reward for anyone who can endure the traditionally long delivery times. Two "el Capitan" mounts are working in the Antarctic for several years now, even at temperatures of -75°C. They are perhaps the most spectacular example of the durability of the sturdy Astro-Physics mounts and are representative for many more exemplars that often run for decades at our customers without failures. With a very accurate manufactured worm gear the Astro-Physics mounts are equally well-suited for smooth, effortless tracking of celestial objects as well as for all visual and photographic purposes. Astro-Physics supplies 4 mounts with 30kg to 135kg instrument load. The GTO 1100 and GTO 1600 series are especially remarkable, because they are fully transportable - despite their high instrument load. This is possible because the declination axis can be separated from the rest of the mount. Even the GTO 1600, with 90 kg instrument load, can be transported and set up by one person! The connection of the two...
Additional Information
| EAN Code | 4047825041210 |
|---|---|
| Manufacturer | Astro Physics |
| SKU (#) | 1405333 |
| Net weight (kg) | 0.52 |
| Image Field | 40mm diameter |
| Focal Length | 488 mm |
| Focal Ratio | f/5.3 |
| Backfocus | 64,1 mm |
| Optical Format | 35mm Format: 4.2 x 2.9 degrees |
FAQ
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Eyepiece Projection - How good can it get?
HIGH-QUALITY PROFESSIONAL ASTRONOMICAL MOUNTS
Astro-Physics 130mm/ f/6.3 StarFire GTX Refractor "Gran Turismo"
Keeping to the same quality standards that have made the fully-apochromatic refractors legendary, Roland Christen's company has been building German Equatorial GoTo mounts for more than three decades. Their proven stability, accuracy and durability is the reward for anyone who can endure the traditionally long delivery times.
"El Capitano" at Dome C of the Concordia Station in Antarctica"
Two "el Capitan" mounts are working in the Antarctic for several years now, even at temperatures of -75°C. They are perhaps the most spectacular example of the durability of the sturdy Astro-Physics mounts and are representative for many more exemplars that often run for decades at our customers without failures.
Astro-Physics GTO 1600
With a very accurate manufactured worm gear the Astro-Physics mounts are equally well-suited for smooth, effortless tracking of celestial objects as well as for all visual and photographic purposes.
Astro-Physics supplies 4 mounts with 30kg to 135kg instrument load. The GTO 1100 and GTO 1600 series are especially remarkable, because they are fully transportable - despite their high instrument load. This is possible because the declination axis can be separated from the rest of the mount. Even the GTO 1600, with 90 kg instrument load, can be transported and set up by one person!
The separation of RA and DE axis and on the right: The CNC machined dovetail of the RA axis to accommodate the DE axis
The connection of the two components is achieved by a CNC-machined dovetail receptor clamp which has the same uncompromising stability. This is also used by "normal" dovetails.
In the case of the GTO3600, the declination axis can also be separated, but this mount is transportable only to a limited extent and better used as a stationary mount.
At the moment, the GTOMACH2 Universal Robotic Mount is the only mount of German design in its weight class, in which ALL cable connections to the telescope (CCD camera, electric focusing, etc.) are passed through the polar axis. The Mach 2 GTO replaces the long proven Mach 1 GTO of Astro-Physics. Universal Robotic means that Mach2 fulfills all of the requirements of a robotic mount for automated operation for imaging, satellite tracking, comet tracking, star survey work and others.
State-of-the-art CNC machine technology and hydraulic circular grinding machines
All parts of Astro-Physics mounts have been CNC-machined and milled out of solid aluminum. In this way, it is possible to circumvent the expensive, labor-intensive production of blanks made of aluminum sand casting.
By using state-of-the-art CNC machining techniques, where surface and angular(!) accuracies of 1 micron allow highly accurate fits, all "blind" volumes of axis and housing parts that do not contribute to the rigidity of the design are erased from the solid aluminum.
Due to the ingenious combination of two tapered roller bearings and three thrust bearings in each of the two housing parts, the axles themselves are even more relieved and stabilized by the shape of the axle housing. This results in a mount of high rigidity and freedom from vibration with a surprisingly low weight.
Features of GTO Servo Drive (applies to all 4 models)
Why does Astro-Physics choose servomotors instead of stepper motors to drive their mounts?
The torque and thus the acceleration of stepper motors reaches their maximum value at low frequencies and drops sharply at high frequencies. Therefore, relatively large motors are necessary to develop enough torque for positioning at the required speeds. At low speeds, so like during normal tracking, such engines have far too much force and then often run uneasily, which can easily lead to vibrations of the telescope.
In addition, stepper motors have natural resonances. In these frequency ranges, the smoothness deteriorates again rapidly. Servo motors, on the other hand, are characterized by high torque even at high speeds, very good running smoothness over the whole speed range and higher efficiency. In order to obtain the same positioning accuracy as with stepper motors, however, a higher electronic effort must be driven.
All functions of the servo drive can be controlled from a laptop or PC. Astro-Physics has a fully supported, working ASCOM V2 driver for all Astro-Physics GTO mounts. This is the recommended method for controlling the mount with a personal computer under the Windows operating system. Please refer to this link http://www.astro-physics.com/index.htm?products/accessories/software/ascom/ascom für weitere Informationen und Links zu der ASCOM-Plattform und dem Astro-Physics V2 ASCOM-Treiber.
GTOCP4 Controll Box for Servo Drive (for GTO-1100, GTO-1600, GTO-3600, GTO Mach1)
All GTO mounts produced since 1998 can easily be upgraded.
For the new GTO-Mach2 Universial Robotic Mount Astro-Physics has developed a new control system (GTOCP5) which combines the precision performance of the Renishaw Resolute Absolute Encoder with the whisper-quiet motion of brushless micro-step servo motors to produce a very accurate observatory-grade mount that can also be set up in just a few minutes in the field. The mount can be operated manually via the clutches or electronically with the encoder loop providing the pointing and tracking functions.
Some Features of the GTOCP4:
- completely redesigned with modern chip technology, resulting in faster processing speed and increased memory capacity for future feature additions
- GTOCP4 supports floating point operands to improve calculation accuracy and coordinate conversions
- includes features from the latest version of the GTOCP3
- Backward Compatibility: All of this is in a compact size that fits all previous GTO mounts (400 GTO, 600 E, Mach 1, 900/1100/1200/1600 and und 3600 GTO)
Further information and technical details about the GTO Control Box are available here.
GTo in Perfection via Handcontroller (optional)
ALL Astro-Physics mounts with servo motors are controlled via the GTO control system and can be operated completely via the keypad. The interface between the hand control and the mount is the GTO control box. It is mounted directly on the pole block, except at the MACH1. There, the GTO control box is attached at the tripod.
The Keypad can be used with all versions of the Astro-Physics GTO Control Boxes: GTOCP1, GTOCP2, GTOCP3 and GTOCP4.
The Keypad is intuitive and easy to use and is equipped with great features to make the observing session productive and pleasurable. Entering long, hard-to-remember keyboard sequences has been deliberately avoided.
This "handheld computer", which even cold winter nights can not harm, is the usual hand control box for controlling the mount equipped with a variety of options:
- programming of the periodic worm error and the gear play in right ascension and declination are possible, of course
- fully automatic positioning of the mount on the object you have entered
- a choice of different correction and pointing speeds are available
- contains more than 17,000 objects in extensive databases
- mehrere eingebaute Software Routinen erlauben eine schnelle und einfache Justierung der Polachse
- several built-in software routines allow quick and easy polar alignment
The control software can be updated via internet. A PC or laptop is not needed. If required, all mounts can also be controlled via the following external software packages:
- PulseGuide
- TheSky
- GUIDE
- Desktop Universe Earth Centered Universe (ECU)
- SkyMap Pro
- Starry Night Pro
- any software that is ASCOM compliant. .
Further information and technical details about the GTO Keypad is available here.
Further information and technical details about the Astro-Physics German Equatorial Mounts is available here:
Astro-Physics GTO-1100 (various versions available)
Astro-Physics GTO-1600 (various versions available)
Astro-Physics Mach2GTO Mount (#1401372 , € 16050,-)
Astro-Physics GTO-3600 (various versions available)
Delivered over a period of almost 15 years, the GTO 1200 is no longer available and will be replaced by the GTO 1600. The Mach 2 GTO replaces the long proven Mach 1 GTO of Astro-Physics.
Accessories for the GTO mounts from Astro-PhysicsOf course, there are many mechanical accessories for the mounts - from the instrument mounting plate to dovetail clamps to the transportable pier. - For details, see our Astro-Physics price list or visit the Astro Physics website (www.astro-physics.com).
