No gear, and no worm and no belts : no maintenance, no mechanical wear, no summer-winter gear and worm tuning .
Absolute encoders : no periodic error, accurate positionning and speed accuracy, very smooth motion.
High speed and noiseless slewings ( up to 20°/sec)
Long unguided exposures (15 min with 2m focal length) : guiding camera is gone !
This mount has current loss magnetic brakes to ensure telescope tube safety
Because axis have large hollow, any cables for CCD camera and any instruments can be passed thru the axis.
On startup the mount knows where it is located on the sky due to absolute positionning system.
Directdrive mounts are used in recent professional telescopes mounts and is the state of the art of telescope mount, and ALCOR-SYSTEM is proud to introduce the NOVA 120 mount.
NOVA 120 mount. Set in Equatorial mode. This item weights 95 kg and has more than 120 kg of possible payload
Directdrive mounts are the best performing mount in the world and here are in a nutshell the main advantages:
This mount has been extensively tested during many years of operation and has proven to be very efficient, accurate and reliable. The next image show a payload test with 120 kg of steel and concrete cylinder, and the mount could be operated up to 20°/sec flawlessly.
Optionnal parts :
Counterweights, 5 and 10 kg on request
Pier (see below)
Laser polar finder
The software is a very advanced software, that includes Tpoint pointing model, as well as speeds model to compensate for non perfect polar alignement. It has an ASCOM interface, so that any ASCOM compliant software can drive the mount.
The Nova 120 mount works so close to perfection, that if the Optical Tube Assembly (OTA) is stiff, it can acheive long unguided exposures. Here is a raw image of a 15 minutes unguided exposure, where no star trail or elongatin is visible. The scale is 0.85/arcsec/pixel. Please download here manual about pointing model (PDF).
The next image is recorded with Nova 120 mount where the polar axis that was offset, on purpose, by 5 arcmin from the pole. A 10 minute un-guided image shows that the polar alignment is so bad that the stars are all trailing ! This is normal because the speed model has been disabled. The pointing model is based on T-POINT.
The usual limitation of unguided exposure time is not from the mount, but from the OTA stiffness !
If the tracking/speed model (from the pointing model) is enabled within the software mount, the mount can compensate for bad polar alignment, and the next un-guided tracking of 10 minutes exposure is perfect.
The next image shows a fast moving asteroid, 2006 DP 14, located at 0.08 ua from earth. The speed of the asteroid is 12 arcmin per hour, both RA and DEC directions. A single 300s un-guided exposure shows the trail due to the motion of the asteroid.
The mount (and the software) can compensate for such a speed, and move the mount at the asteroid motion rate (plus the sidereal rate, refraction rate and tracking model rate). The next image shows a 600s exposure with speed object enabled. The asteroid is pin point sharp and this is not anymore required to split the exposures so that the asteroid does not trail !
Joaquin Fabrega is an happy user of the mount. He has put a 400 mm F3.5 telescope with a FLI 16803 CCD camera. This setup has no guiding CCD. This setup has been running since January 2014, and has produced very nices images and thousand of asteroid position measurement. This telescope is been operated remotely from Panama. The next image of NGC 253 has been achieved with several unguided 10 minutes exposures.
NGC 300, no auto guiding has been used. Final image stacked from several exposures from 5 to 10 min according to seeing figures.
Windows 7,8 and 10 ASCOM compliant software is available here
The mount is able to perform earth artificial satellite tracking, based on satellite TLE that is used to predict their trajectory. This can be possible with low orbit satellites such as ISS. The mount prepares it position on the satellite path, and start tracking when the satellite appears over the horizon. The mount software can retrieve from the internet TLEs and perform computations of the satellite pass.
The next video shows the tracking of 22803 (SL-16 R/B) satellite that has an altitude of 850 km, and travels at ~ 1°/sec in the sky, the mount tracked the satellite within an arc of 120°
Please be aware, that no additional camera and close loop system based on image guiding has been used. This is the performance from an "open loop" track based on software and encoders. The scale of the image is 4 arcsec per pixel. Click on the image to get the AVI file (120Mo)
Please do not hesitate to ask questions about this feature.
NOVA 120 mount. The mount is set in ALT-AZ mode, with a small RC Ø250mm diameter.
The next image shows a raw unprocessed snapshot of Messier 27, this is a single 300s raw exposure, H-Alpha 5 nm filter, with the mount set in ALTAZ mode ("Polar axis" aiming to the zenith) A derotator has been used, to compensate for field rotation. A pointing and speed model has been used to perform this image. Stars are very round, and tracking performance is very good. Image sampling is 0.8 arcsec/pixel. FWHM is 2.5 arcsec and elongation is 7%
The mount is perfectly able to blind track ISS as the image demonstrates below. A Ø250 mm RC with 2m of focal length has been attached to the NOVA 120 mount, and there's no camera to track the satellite, this is only based on TLE and pointing model. This was is called blinded tracking, there is no guide camera and feedback from it. The pixel scale is 0.24 arcsec and the International Space Station was present in the camera at the telescope's focal plane. 2ms exposure time has been used. Click here or over image to get the full video.
Please send email to get the documentation of this product.
I am the owner of the SPACE observatory (San Pedro de Atacama Celestial Explorations), and managing 15 robotic telescopes. I have seen, put into service and maintained many types of mount, optical tubes, and camera systems since many years. This experience tells me what works and what does not. Or what works but don't last. Here, in one of the best place on Earth to observe the sky with about 320 clear nights a year (record was between September 2013 to September 2014, where we had 345 clear nights), there is a high demand on the equipment. Old technology mounts (with worm gears and gears) require autoguiding, and require yearly dismounting, putting the hands in the grease, and in the end, very often have to be returned to their makers. Since several years, I have encouraged my clients to rely only on direct drive mounts, since they slew very fast and precisely, can track very long exposures perfectly without autoguiding. They are not for any use, not for portable setups, not for setups which do change every so often. They are made for fixed observatories, require the whole system to be well balanced, and are supposed to be used in this configuration for years, in remote mode. But when setup correctly, they are fantastic performers, making you to forget them. Their performance is limited by the quality of the optical tube. If your optical tube is flexible, or if something moves, this will be the limit of your system. I have 3 Nova 120 operating at the observatory. One of them I used during a year on an asteroid survey, which was controlled by a script written in PRISM scripting language. It ran, and ran and ran, never had a single problem. When you spend a lot of money on a high end mount, you want it to work, and not providing you any problems, either with unfinished software, and trailed images. That's why I recommend strongly NOVA mounts. For my last project, a 45 inch Newtonian, I relied on similar electronics from Alcor Systems, using high quality components and stable software.
A high quality pier mount can be provided, it is made of sand blasted stainless steal. Flatness of the mount can be adjusted accurately. This pier can be let outdoor, it will not be damaged by moisture, rain or snow. it fits perfectly to NOVA 120 mount.
All necessary counterweights can be supplied, weight is 10 kg or 5 kg