In a previous blog (>>here<<) and FaceBook post (>>here<<) earlier this week, we introduced 10Micron and gave an overview of their current mount range. The current 10Micron German equatorial mount range can be summarised in the image below.
In this first introductory article
, we will look at the mid-range 10Micron GM2000 HPS II (GM2000 from now on) German equatorial mount, and how it is assembled. The GM2000 has an instrument payload carrying capacity of 50kgs, and the weight of the equatorial head is 33kg which still makes it transportable by one person. We should point out that although there are four models in the 10Micron German equatorial mount lineup, as the image above shows, there are actually five models. The GM2000 model is available in two versions - a Monolithic version
(i.e. single all-in-one) and an Ultraport version
where the mount splits into two sections making it easier to transport for field use. In this, and subsequent related posts, we will be looking at and discussing the Ultraport version of the GM2000.
Here we'll look at the individual parts of the mount, and how they are fixed together to build up the mount as if it was going to be used for astronomy use - think of it as a sort of short photographic "journey". We will also take a close up look at some parts of the mount that maybe are not clear (or are not seen) from the standard photographs available online.
The 10Micron Centaurus II heavy Duty tripod
The GM2000 mount comes with the optional heavy duty Centaurus II tripod
which is shown above. This is a very sturdy exceptionally well made tripod. The whole tripod is CNC machined with ERGAL-alloy tubing for the legs. ERGAL is an aluminium alloy that has very good fatigue strength and resistance to corrosion. Although it may not look it from the photograph, the tripod weighs a hefty 21kg! It's height can be adjusted from 0.9m to 1.35m. At the base of the tripod is a Cordura "triangle" which serves as an accessory tray for e.g. power supply. The tripod can easily
carry the weight of the GM2000 (33kg) and any payload (up to 50kg); the tripod is tested to carry up to an amazing 200kg of weight! The Centaurus II tripod comes supplied in a Cordura carry bag for storage and transportation (not shown in the photographs).
Tripod close up view
The built-in bubble level which can be seen near the top of the tripod nearest the camera, and helps with accurate levelling of the tripod. The top of the tripod has the mount plate base adaptor installed. This plate is originally is fitted to the base of the GM2000 mount (out of the box) and is removed and installed on the tripod as shown prior to the mount being fitted. The azimuth block (for aiding fine azimuth mount adjustment) is also shown already fitted. On the underside of the tripod are three hooks where the control box and the keypad may be hung so they are kept safely out of the way.
The anti-vibrating, anti-sink feet pads are self levelling so that the tripod will sit well on uneven ground. For fine adjustment in levelling the tripod, each foot has a fine height adjuster with a locking knob (the two large silver knobs above the black foot).
Tripod height adjustment locking knobs
Here is a close up of the large ergonomic height adjustment locking knobs. There are two on each leg - one at the top and one at the bottom. Each locking knob is approximately 70mm in size so they can easily be locked/loosened even when wearing gloves. The tripod legs are very well made and are very sturdy with the outer two tripod legs being approx. 35mm in diameter, with the central leg being 50mm in diameter.
Right Ascension axis main body of the GM2000
Here you can see the main RA body of the GM2000 attached to the Centaurus tripod ready to accept the DEC body housing. On the mount, the knurled azimuth and altitude adjusters can be seen along with the (light grey) electrical connector for the DEC assembly at the top.
Side view of the GM2000
This close-up side view of the mount shows the two silver knurled altitude locking knobs (bottom right) and the altitude adjustment knob (bottom left). These knobs can be tightened/loosened by hand, or by using an allen key supplied with the mount. Two of the RA (Y-shaped) clutch knobs can be seen near the top which, when loosened, allows free-movement of the RA axis. The RA axis features internal hard-stops to prevent internal wiring from being stretched and snapping. At the top are two rounded silver "bullet-like" cylinders, which are alignment pins, that are used for helping to locate and align the DEC axis body onto the mount when it is being fitted. In the centre is the industrial-grade electrical connector for the DEC axis body's motor and electronics.
Plan view of the RA axis body
Looking down on the GM2000's RA axis body of the mount, the electrical connector and the 2 locating pins can be seen. The asymmetric shape of the electrical connector means that the DEC body can only be installed one way only.
Declination axis body
Here you can see the DEC axis body which houses the DEC motor & gearbox, encoders and associated electronics. Two of the DEC axis body assembly locking knobs can also be seen. The weight of the unit is 15kg. A jar of marmalade was left on the table after breakfast to give an idea of scale of the declination axis body! :-)
The GM2000 comes without a dovetail clamp, leaving you to choose what particular version of clamp you may want for your equipment. There are numerous models available, including a dual Vixen/Losmandy version. The one shown here, above, is the 3"-wide Losmandy style model. The four hex bolts that secure the clamp to the clamp end of the DEC-axis body can be seen. The two silver coloured knobs on top of the clamp are the clamp locking knobs for securing whatever telescope (and accessories) are used in the clamp.
Counterweight shaft entrance port
Here you can see the counterweight shaft end of the declination axis body. This is where the counterweight bar screws into the DEC axis. The counterweight bar is always attached after the DEC axis body is attached to the main RA body of the mount.
Underside of DEC axis body
Here you can see the underside of the Declination axis body. The two large holes near the edge of the underside are the alignment holes for the (alignment) pins seen in a previous image on the RA body. The four silver DEC assembly locking knobs can be seen around the edge. When these knobs are tightened, they push dovetail-shaped pins that slide into the dovetail groove on the main RA body of the mount (see photo 6: side view of the GM2000) and secure the DEC housing to the rest of the mount. In the middle is the industrial-style electrical connector for the DEC electronics/motor.
Close up of underside of DEC axis body
A close-up of the underside showing the industrial-grade DEC axis body electrical connector in more detail.
Declination assembly fitted
The DEC assembly has now been connected (mounted) on the mount and the securing knobs have been tightened for secure fitment. The mount is now ready to accept the dovetail bar, counterweights and other mount-related components and accessories.
Counterweight shaft and counterweights
The stainless steel counterweight shaft is 40cm long, 4cm in diameter and weighs a hefty 4kg. The two optional 6kg (right) and 12kg (left) counterweights are made from rustproof and scale resistant (V2A) stainless steel.
Counterweight shaft and counterweight attached
The counterweight bar has been fitted to the GM2000 mount and one of the counterweights (6kg) has been attached ready to accept a telescope.
Control box and accessories
The GM2000 mount control box is at top right inside its protective padded case. When closed, the padded case completely wraps around the control box so it covers the connection ports to keep them clean. The case also features a loop strap so it can be hung from one of the hooks on the underside of the Centaurus II tripod. The power lead (black and red cable) to connect the control box to an authorised power supply is on the left, and the GM2000 control box-to-mount connection cable (black cable) is below the control unit. The GM2000 also comes with an Ethernet cable (grey cable) for the mount to be controlled from a PC. To the left of the control box is a remote power switch connection lead so that the mount can be switched on/off remotely via an external relay box. You may be wondering what the black knob unit is above the grey network cable is? It is supplied as standard to help lock and unlock the Y-shaped RA/DEC axis clutch knobs.
Close-up of the GM2000 control box
This is a close-up view of the control box front panel which contains the brains and some electronics for operating the mount. The connection ports for the handset, power supply, autoguider, and a serial and LAN port for PC connection (if needed) can all be seen. It should be noted that the large circular mount-to-control box, hand/keypad-to-control box, aux and power supply ports all feature screw lock-ring type secure connections, which means the cables cannot be accidentally pulled out.
This is the hand controller keypad for the GM2000 mount and is the communication interface between the mount and user. It has an illuminated red colour 4-line 128x64 pixel display, and also includes an internal heater to keep the display readable during cold nights. The keypad allows you to enter parameters such as date, time and location and also has shortcuts for celestial objects such as planets, stars, Messier objects etc. The keys are large in size so they can be used when using gloves. The keypad-to-control unit connector is also of the screw on lock-ring type for a secure connection and means the cable cannot be accidentally pulled out. The handset comes with a protective cover to keep it safe from dew and from scratches and has a transparent front allowing you to read the display and easily press any of the keys. The cover also features a loop so the handset can be hung from e.g. one of the tripod hooks.
This is a 10Micron-approved 240V AC to 27V DC regulated/stable power supply for the GM2000. 10Micron have a short-list of power supplies that can be used with their mounts and we list them on our website >>here
Nearly ready to go!
Here the connector cables from the mount to control box, handset to control box and the power supply have all been connected. The control box is hung from one of the hooks on the underside of the tripod, while the handset is hung from the upper tripod leg lock screws for accessibility. The power supply is placed on the Cordura accessory tray so it is safely out of the way and off the ground.
A 120mm APO refractor, with tube rings and Losmandy dovetail bar, is now attached and clamped to the GM2000 mount. The RA and DEC clutches were loosened and the counterweights and position of the telescope in it's tube rings were adjusted so both axes were balanced.
Ready to go!
Now the mount is all set up, and telescope is on, and all ready for a night's astronomy. Attached to the focuser of the telescope in the image above is the Baader DADOS spectrograph
(white cube unit). Of course with such a high quality set up it needs to be guarded .... and our (adopted) 7 year old Rhodesian Ridgeback, Kaizer, took on his role admirably.
We hope you have enjoyed this basic introductory blog on the set up of a GM2000 HPS II Ultraport
mount. We will be doing more blogs and Facebook posts on this mount in due course, covering more about the tripod, control box, hand controller, controller menu's and much much more. So please stay tuned. However, please do get in touch if you have any questions about any of the above photographs or if you need any more information. We are very happy to help.