Orion Sirius Pro AZ/EQ-G User manual

IN 550 Rev. A 09/15
INSTRUCTION MANUAL
Orion©Sirius™Pro AZ/EQ-G
GoTo Telescope Mount
#10088
Customer Support:
www.OrionTelescopes.com/contactus
Corporate Offices:
89 Hangar Way, Watsonville CA 95076 – USA
Providing Exceptional Consumer Optical Products Since 1975
Copyright © 2015 Orion Telescopes & Binoculars
All Rights Reserved. No part of this product instruction or any of its contents may be reproduced, copied, modified or adapted,
without the prior written consent of Orion Telescopes & Binoculars.

2
Table of Contents
Part 1: UNPACKING ...........................3
1.1 Unpacking .................................. 3
1.2 Parts List ................................... 3
Part 2: ASSEMBLY ............................4
2.1 Setting Up the Pier Tripod (“Pier-Pod”) ............ 4
2.2 Attaching the Counterweights ................... 4
2.3 Attach the Hand Controller Bracket............... 5
2.4 Installing a Telescope on the Mount .............. 5
2.5 Balancing the Telescope ....................... 5
PART 3: USING THE SIRIUS PRO AZ/EQ-G MOUNT 7
3.1 Manually Rotating the Mount.................... 7
3.2 Using the Setting Circles....................... 7
3.3 Adjusting the R.A. Axis Elevation (Latitude) ........ 8
3.4 Setting the Mount to Alt-azimuth Mode ............ 8
3.5 Mounting a Second Telescope (Altazimuth mode only) 9
PART 4: POLAR ALIGNMENT ..................10
Figure 1. The Sirius Pro AZ/EQ-G mount
PART 5: DRIVE PANEL INTERFACE .............10
5.1 Panel Interface Components: .................. 10
5.2 Pinout of the Interfaces ....................... 12
5.3 Attaching the SynScan GoTo Hand Controller ..... 12
5.4 Power Supply Requirements................... 12
PART 6: OTHER SIRIUS PRO AZ/EQ-G FEATURES 12
6.1 Auxiliary Encoder Function .................... 12
6.2 Permanent Periodic Error Correction ............ 12
6.3 Batch Exposure Function ..................... 13
SUGGESTED ACCESSORIES ..................13
SPECIFICATIONS ............................14

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Part 1: UNPACKING
1.1 Unpacking
The entire mount will arrive in two boxes, one containing the
pier tripod (the “pier-pod”) and two counterweights, the other
containing the mount head and hand controller. Be careful
unpacking the boxes. We recommend keeping the boxes and
original packaging. In the event that the mount needs to be
shipped to another location, or returned to Orion for warranty
repair, having the proper packaging will ensure that your mount
will survive the journey intact.
Figure 2. Components included with the Sirius Pro
Camera shutter control cable
Pier-pod
SynScan
hand controller
Counterweight
shaft extension
Dec. cable
Allen wrenches
Serial cable
12V DC power
cable
Secondary
saddle
Tripod
Mount head
7.5 lb. Counter-
weights
Hand controller
coil cable
Hand controller
bracket
WARNING:
• NeverlookdirectlyattheSunwiththenakedeyeorwitha
telescope–unlessyouhaveapropersolarfilterinstalled
overthefrontofthetelescope!Otherwise,permanent,
irreversibleeyedamagemayresult.
• NeveruseyourtelescopetoprojectanimageoftheSun
ontoanysurface.Internalheatbuild-upcandamagethe
telescopeandanyaccessoriesattachedtoit.
• NeveruseaneyepiecesolarfilteroraHerschelwedge.
Internalheatbuild-upinsidethetelescopecancause
thesedevicestocrackorbreak,allowingunfiltered
sunlighttopassthroughtotheeye.
• Neverleavethetelescopeunsupervised,eitherwhen
childrenarepresentoradultswhomaynotbefamiliar
withthecorrectoperatingproceduresofyourtelescope.
Make sure all the parts in the Parts List are present. Be sure
to check the boxes thoroughly, as some parts are small. If
anything appears to be missing or damaged, immediately call
Orion Customer Support (800-676-1343) or email support@
telescope.com for assistance.
1.2 Parts List
Qty. Item
1 Sirius Pro mount equatorial head
1 Counterweight shaft extension, 120mm
1 Secondary saddle plate
1 SynScan hand controller with coil cable
1 Pier tripod
2 7.5-lb. counterweights
1 Bracket for SynScan controller
1 RS-232 serial cable
1 Shutter release cable (Canon)
1 12V DC power cable with auto lighter plug
1 Dec. cable
1 Set of Allen wrenches

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Part 2: ASSEMBLY
2.1 Setting Up the Pier Tripod (“Pier-Pod”)
1. Fold the tripod legs down until they stop, then screw the
leg lock knob until tight (Figure 3).
2. Loosen the two azimuth adjustment knobs until there is
½" or more of space between the two bolt ends (Figure
4A). Then place the mount on the tripod, aligning the
metal post on the tripod with the gap between the two
azimuth adjustment bolts (Figure 4B).
3. Once the mount is seated on the pier, slightly tighten the
two azimuth adjustment knobs.
4. While supporting the mount head with one hand, turn
the mount coupling knob (on the flexible cable) clockwise
until tight; this firmly attaches the mount head to the pier
(Figure 5).
5. Extend the tripod legs to the desired length (Figure
6A). Use the built-in bubble level (Figure 6B) to level
the mount by adjusting the length of the tripod legs as
needed.
2.2 Attaching the Counterweights
Always attach the counterweight(s) before installing your tele-
scope on the mount!
1. Loosen the two counterweight shaft lock knobs (Figure
7) and fully extend the retractable shaft. Then re-tighten
the two knobs to secure the shaft in place.
2. Loosen the right ascension (R.A.) clutch wheel (Figure
8), and rotate the R.A. axis until the counterweight shaft
is pointing downward, as shown.
3. Remove the knurled “toe saver” safety stop (Figure 7)
from the end of the counterweight shaft.
4. The Sirius Pro mount comes with a 120mm
counterweight shaft extension (Figure 9), which
can be installed at this point if desired for balancing
heavier payloads. Thread it into the end of the main
counterweight shaft until tight.
5. Slide one or both of the 7.5-lb. counterweights onto the
counterweight shaft, depending on the telescope’s weight
Figure 4. A) Loosen the azimuth adjustment bolts to create
at least a ½" gap. B) Orient the mount head so that the gap
aligns with the metal post on the tripod.
Figure 3. Fold the tripod legs down and lock each one with
the captive rosette knob.
Post
A
B
Azimuth adjustment bolts
Gap

5
(Figure 10); first loosen the counterweight’s lock knob to
clear the center hole. Retighten the lock knob to secure
the counterweight(s) on the shaft.
6. Replace the safety stop on the end of the counterweight
shaft. The safety stop prevents the counterweights from
falling on your foot if the lock knobs come loose.
2.3 Attach the Hand Controller Bracket
Attach the hand controller bracket to the pier by wrapping the
strap around the pier and fastening it with the hook-and-loop
closure (Figure 11).
2.4 Installing a Telescope on the Mount
1. The Sirius Pro mount is designed to hold a telescope
payload of up to 30 lbs. in EQ or single scope Altazimuth
mode. In dual scope altazimuth mode it can hold up to
two 30-lb. telescopes. For heavier telescopes, the mount
may not provide sufficient stability for steady observing
or imaging.
Before installing a telescope, be sure that:
a. The counterweight shaft is pointing toward the
ground.
b. The counterweights are installed on the
counterweight shaft and have been moved to
the bottom end of the shaft.
c. The R.A. axis is secured by tightening the R.A.
clutch.
2. Loosen the Dec. clutch wheel and rotate the saddle until
the slot is oriented horizontally, as in Figure 12A. Then
retighten the Dec. clutch wheel.
3. Loosen the two knobs on the saddle plate (Figure 12B)
until the bolts are clear of the dovetail slot.
4. While holding the telescope, seat the dovetail bar of the
telescope into the saddle. Then tighten the two knobs to
secure the dovetail bar.
NOTE: The Sirius Pro saddle is designed to accept a
“Vixen-style” dovetail plate, or bar.
Warning: Keep supporting the telescope until the dovetail
mounting bar is tightened down firmly in the saddle!
Figure 5. Turn the large knob on the flex cable clockwise to
attach the mount head to the pier-pod.
Figure 6. A) Use the leg extension knobs to adjust leg
length. B) Level the mount using the bubble level and
adjusting leg length as needed.
Mount coupling
knob
Bubble level
Power indicator
(LED)
ON/OFF switch
A.
B.

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2.5 Balancing the Telescope
To minimize stress on the motor drive system and ensure
smooth, accurate movement of your telescope on both axes,
it is imperative that the optical tube be properly balanced. We
will first balance the telescope with respect to the right ascen-
sion (R.A.) axis, then the declination (Dec.) axis, in the equato-
rial mode.
1. Keeping one hand on the telescope optical tube, loosen
the R.A. clutch wheel. Make sure the Dec. clutch wheel
is tightened, for now. The telescope should now be
Figure 8. The R.A. clutch wheel.
Figure 9. The 120mm shaft extension threads into the
counterweight shaft.
Figure 11. The hand controller bracket should be strapped
around the pier-pod.
Figure 7. Loosen the two counterweight shaft lock knobs to
extend or retract the counterweight shaft.
Figure 10. Install counterweight(s) before attaching your
telescope to the mount!
Dec. clutch
wheel
Counterweight
shaft lock knobs
Satety stop
R.A. clutch wheel
Extension
Bracket
a.

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able to rotate freely about the R.A. axis. Rotate it until
the counterweight shaft is parallel to the ground (i.e.,
horizontal).
2. Now loosen the counterweight lock knob and slide the
weight(s) along the shaft until it exactly counterbalances
the telescope. That’s the point at which the shaft remains
horizontal even when you let go with both hands. Once
balance is achieved, retighten the counterweight lock
knobs.
3. To balance the telescope on the Dec. axis, first tighten
the R.A. clutch, with the counterweight shaft still in the
horizontal position. Then with one hand on the telescope
optical tube, loosen the Dec. clutch and check for
any spontaneous rotation. If there is some, adjust the
telescope forward or back in the saddle or in its tube
rings until it remains horizontal when you carefully let
go of it. (It’s best to return the telescope to an upright
position before adjusting it forward to back in the saddle!)
The telescope is now balanced on both axes. When you loos-
en the clutch on one or both axes and manually point the tele-
scope, it should move without resistance and should not drift
from where you point it.
PART 3: USING THE SIRIUS
PRO AZ/EQ-G MOUNT
3.1 Manually Rotating the Mount
The mount can be moved manually by simply loosening the
R.A. and Dec clutches and pointing the telescope to the
Figure 13. R.A. and Dec setting circles can be used to
locate objects “the old fashioned way.”
Figure 12. A) Loosening the Dec. clutch wheel lets you
rotate the dovetail saddle to a horizontal position. Be sure to
tighten the clutch before installing your telescope! B) Tighten
the two rosette knobs to secure your telescope in place.
Saddle
Locking
thumbscrew Arrow (pointer)
R.A. Setting circle
Dec clutch
wheel
A
B
Knobs
Saddle oriented
horizontally
Arrow (pointer)
Dec. Setting circle
Locking
thumbscrew

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desired location. Both the R.A. and Dec. clutches should be
tightened when driving the mount with the internal motors.
3.2 Using the Setting Circles
As indicated in Figure 13, the Sirius Pro features right ascen-
sion and declination setting circles. Most users of a GoTo tele-
scope will not have a need to use setting circles, but if you
should, here’s how:
1. Before using the setting circles, they will need to be
calibrated. Point the telescope toward a known object
whose coordinates you have looked up (R.A.-Dec.
coordinates or azimuth-altitude coordinates). Loosen the
two locking thumbscrews on the setting circles and turn
them so the coordinate values line up with the arrows,
then retighten the locking screws.
2. Once the setting circles are calibrated, the mount can
be moved either electronically or manually to specified
coordinates by referring to the setting circle readings.
3. The R.A. setting circle features three different scales:
the lower scale is used to indicate the right ascension
in Equatorial mode when operating in the Southern
Hemisphere; the middle scale is used to indicate the
right ascension in Equatorial mode when operating in the
Northern Hemisphere; the upper scale is used to indicate
the azimuth angle when operating in Altazimuth mode.
4. The lower scale of the Dec. setting circle is divided
into four quadrants of 90-degrees, used to indicate the
declination (when mount is operating in Equatorial mode)
or altitude angle (when operating in Altazimuth mode).
Use the proper quadrant when calibrating the Dec.
setting circle.
3.3 Adjusting the R.A. Axis Elevation (Latitude)
1. Loosen the altitude lock knob located on the left side of
the mount (Figure 14) about a quarter turn.
2. Push the spring-loaded elevation adjustment handle to
engage it, then turn it clockwise or counterclockwise
to set the R.A. axis elevation to your location’s latitude.
When the handle reaches its limit of rotation, release it,
then change its orientation and push it in to engage it
again and continue turning it.
3. Refer to the latitude scale and pointer on the right side of
the mount (Figure 15). (If you don’t know your latitude,
consult a geographical atlas or look it up on the internet.)
For example, if your latitude is 35° North, set the pointer
to 35. The latitude setting should not have to be adjusted
again unless you move to a different viewing location
some distance away.
4. Retighten the altitude lock knob.
Note: It is normal to have slight elevation play on the Sirius
Pro AZ/EQ-G mount. The mount depends on the gravity of its
payload and its own weight to stay firm. Because of this, it is
recommended to end the elevation adjustment with an upward
movement. Whenever there is an upward over-adjustment,
lower the elevation first, and then crank the mount upward
again.
Figure 14. Loosen the altitude lock knob before adjusting
the mount’s elevation angle.
Figure 15. In EQ mode, line up your latitude on the scale
with the pointer (arrow).
Altitude lock
knob
R.A. clutch
wheel
Elevation
adjustment
handle
Elevation
adjustment
handle
Polar scope
mounting
plate
Latitude
scale
Arrow
(pointer)
a.
3.4 Setting the Mount to Alt-azimuth Mode
1. Refer to Section 3.3 to adjust the R.A. axis’s elevation.
2. Use caution when the latitude indicator gets close to
90 degrees. Do not turn the spring-loaded elevation
adjustment handle further when you feel it is blocked,
because it may mean that the R.A. axis has reached
the factory-calibrated position for Altazimuth mode.
TURNING THE HANDLE FORCEFULLY WILL DAMAGE
THE MOUNT.
3. Tighten the Altazimuth mode lock knob to secure the
R.A. axis in position for altaz mode operation (Figure
16). Use a 5mm Allen wrench to tighten the knob if
necessary.
4. Also tighten the altitude lock knob on the left side.
Figure 17 shows the mount set in Altazimuth mode, with one
counterweight installed.

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5. To restore the mount to Equatorial mode, loosen the
altitude lock knob first, then fully release the Altaz mode
lock knob. DO NOT FORGET TO DO THIS! Use the
spring-loaded elevation adjustment handle to lower the
mount to the desired elevation.
Note:
• In any case, DO NOT TURN THE HANDLE
FORCEFULLY.
• In Altazimuth mode with one telescope mounted, the
telescope should be positioned on the right-hand side
of the mount when viewed from behind the mount. The
counterweight shaft should be extended to the left.
• When switching between Altazimuth and Equatorial
modes, be sure to remove the telescope (first) and all
counterweights (after scope has been removed) from
the mount to avoid damage to the mount’s latitude
adjustment mechanism.
• It may be more difficult to balance the R.A. (or Azimuth)
axis in Altazimuth mode. Here are the balancing steps
recommended for Altazimuth mode:
» Balance the payload and counterweights in equato-
rial mode and mark the position of the counterweights.
» Unload the payload and counterweights to set the
mount in Altazimuth mode.
» Re-load the mount again by installing the counter-
weights at the marked position.
3.5 Mounting a Second Telescope (Altazimuth
mode only)
A secondary telescope saddle is included with the Sirius Pro
mount. It’s designed to be installed on the end of the mount’s
counterweight shaft to hold a second telescope.
1. Slide the counterweight shaft out and rotate it so the flat
strip at the end of the shaft is facing up, then lock the
shaft with the two lock knobs (Figure 18A).
2. Loosen the Allen screw on the secondary saddle’s silver
coupler ring and push the saddle onto the counterweight
shaft, as shown in (Figure 18B). Align the Allen screw
with the flat strip on the counterweight shaft.
3. Use a 5mm Allen wrench to secure the saddle to the
counterweight shaft with the Allen screw in the center of
the saddle (Figure 18C). Also tighten the Allen screw on
the coupler ring with the same wrench.
4. Tighten the Dec. clutch wheel, and then install the
second telescope on the secondary saddle. The second
telescope and its saddle should be situated to the left of
the mount when the telescope points forward.
5. Loosen the counterweight shaft’s lock knobs to test the
balance of the second telescope. Adjust the positioning
of the telescope in its tube rings or the dovetail bar’s
position in the groove of the saddle until the telescope
is balanced. Then retighten the two counterweight shaft
lock knobs.
6. Loosen the Dec. clutch to check the balance of the
telescope mounted on the primary saddle. Make any
adjustments needed, then retighten the Dec. clutch
wheel.
Figure 16. The altazimuth mode lock knob secures the
mount in position for use in altazimuth mode.
Figure 17. All set for single scope use in altazimuth mode.
Altazimuth
mode lock
knob

10
7. Loosen the counterweight shaft’s lock knobs and rotate
the second telescope until it points in the same direction
as the main telescope. Retighten the lock knobs.
8. Aim the main telescope at a distant object, and then
adjust the two vertical-adjustment knobs on the
secondary saddle (Figure 19) to point the secondary
telescope to the same vertical level.
Figure 20 shows the mount in Altazimuth mode with the sec-
ondary saddle installed.
Note:
• Use the secondary saddle only when the Sirius Pro
mount is set up in Altazimuth mode.
• There is no mechanism on both the primary saddle and
the secondary saddle for aligning the two telescopes in
the azimuth direction.
• The 120mm counterweight shaft extension cannot be
used with the secondary saddle.
PART 4: POLAR ALIGNMENT
When you look at the night sky, you no doubt have noticed that
the stars appear to move slowly from east to west over time.
That motion is actually caused by the Earth’s rotation (from
west to east). An equatorial mount is designed to compensate
for that motion, allowing you to easily “track” the movement of
astronomical objects, thereby keeping them from drifting out of
your telescope’s field of view while you’re observing or imag-
ing.
This “tracking” is accomplished by slowly rotating the telescope
on its right ascension (R.A.) axis, using the built in motor drive.
But first the R.A. axis of the mount must be aligned with the
Earth’s rotational (polar) axis—a process called polar align-
ment. The SynScan hand controller provides a highly accurate
polar alignment routine after a 2-star or 3-star GoTo alignment
is performed. Please refer to the SynScan manual for detailed
instructions.
An optional, externally mounted polar axis finder scope
(#7152) is available for the Sirius Pro mount. It can be used
to accurately polar align the mount from both Northern and
Southern Hemisphere locations. For detailed instructions on
how to set up and use the polar scope, refer to the manual for
that accessory.
PART 5: DRIVE PANEL
INTERFACE
5.1 Panel Interface Components:
POWER INPUT JACK: This is a threaded 12V DC power
input jack on the right side of the mount head that provides a
secure connection to the power source (Figure 21). The 12V
DC “cigarette lighter” power cable provided with the mount has
a matching threaded connector for the input jack.
Refer to Figure 22 for the following ports:
HAND CONTROL: This 8-pin RJ-45 jack is for connecting the
coil cable of the SynScan hand controller.
AUTO GUIDE: A 6-pin RJ-12 jack is for connecting an autogu-
ider. It is compatible with any autoguider with an ST-4 type
interface.
SNAP: These two 2.5mm stereo jacks allow connection to two
cameras’ shutter control ports. The SynScan hand controller
Figure 18. For mounting a second telescope in Altazimuth
mode, A) first locate the flat strip at the end of the
counterweight shaft. B) Then install the included secondary
saddle on the shaft with the socket head screw over the flat
strip. Finally, C) tighten the screw running through the center
of the secondary saddle.
Flat strip
Flat strip Allen screw
A.
B.
C.

11
Figure 19. Polaris is easy to find in the northern sky by
extending an imaginary line from the two “pointer stars”
of the Big Dipper. Polaris lies within 1 degree of the north
celestial pole (NCP).
Figure 19. Use the vertical-adjustment knobs on the
secondary saddle to point the secondary telescope to the
same vertical level as the main telescope.
Figure 21. The power input jack and declination motor
cable sockets are located on the right side of the mount
head.
Figure 22. The main drive panel interface.
Figure 20. The mount is ready for installation of two
telescopes.
Autoguider port Hand controller port
SNAP camera
control ports
USB port
Adjustment
knobs
Power input jack
Dec. motor sockets

12
RJ-45 port on the bottom of the SynScan controller. Push the
connector into the port until it clicks into place.
The smaller modular port next to the RJ-45 port on the hand
controller enables serial communication between the Sirius
Pro mount and a computer running astronomy software such
as Starry Night Pro. For that you will need the RS-232 com-
puter interface cable that was included with the mount. If your
computer does not have an RS-232 port, you will also need a
USB-to-serial adapter. Check telescope.com for an available
adapter.
As mentioned in Section 5.1, however, the mount also has an
integrated USB port for direct connection of the mount head to
a computer. If you use this method you would not connect the
computer to the SynScan hand controller.
5.4 Power Supply Requirements
The Sirius Pro AZ/EQ-G should be powered by a 12V DC or
AC-to-DC power supply with a 3-amp or higher output current
rating.
• Output Voltage: DC 11V (minimum) to DC 16V
(maximum). Voltage not in this range could cause
permanent damage to the motor controller board or the
hand controller.
• Output Current: 3A for power supply with 11V output
voltage, 2A for power supply with 16V output voltage.
• Do not use an unregulated AC-to-DC adapter. When
choosing an AC adapter, it is recommended to use a
switching power supply with 15V output voltage and at
least 2A output current.
• If the power voltage is too low, the motor controller will
automatically stop the motors.
PART 6: OTHER SIRIUS PRO
AZ/EQ-G FEATURES
6.1 Auxiliary Encoder Function
The Sirius Pro mount is equipped with auxiliary encoders on
both the R.A. axis and Dec. axis. These enable the mount to
continue tracking even when a user unlocks the clutches and
manually rotates the mount in R.A. and Dec. With this feature,
you can manually operate the mount any time without worry-
ing about losing the mount’s GoTo alignment status. When you
want to operate the mount with the SynScan hand controller
again, no re-alignment is required; all that is needed is to re-
lock the clutches. This feature can be enabled or disabled in
the SynScan hand controller.
6.2 Permanent Periodic Error Correction
The Sirius Pro mount is equipped with an index on its R.A.
worm, thus the motor controller can keep tracking the current
position of the worm. After a proper PEC training routine, in
which the training data is stored in the motor controller per-
manently, a user can start the periodic error correction (PEC)
at any time to improve the tracking performance for astropho-
tography. A training process is not required in the next observ-
ing session (assuming that the polar alignment is always
can control the cameras to take pictures automatically via this
interface. The camera control cable included with the Sirius
Pro mount is compatible with select Canon EOS series DSLR
cameras. It has a right-angle 2.5mm stereo plug on one end
for connection to the drive panel and a straight 2.5mm plug on
the other end for connection to the camera. Cables for other
cameras can be sourced optionally or custom made.
USB Port: The USB port connects to an internal USB-to-serial
device (baud rate 115200 bps). It can be used to control the
mount directly from a host PC, or to update the motor control-
ler firmware.
ON/OFF Switch: Located on the left side of the mount head,
this switch turns power to the mount and hand controller on
and off (Figure 6B).
Power LED: The power LED on the ON/OFF switch serves
as a power-on indicator and provides other status information:
Steady on: Power voltage is normal.
Slow flashing: Power voltage is low; continuing to operate
the mount may damage the battery (if a 12V lead-acid
battery is in use).
Fast flashing: Power voltage is extremely low; continuing
to operate the mount may damage the battery and the
motor controller in the mount.
Intermittent single flash: The PPEC training routine has
been triggered, but the controller board in the mount has
not received the worm index signal and the PE correction
recording has not started yet.
Intermittent double flash: The PPEC training routine has
been started and the controller board in the mount has
received the worm index signal and started to record the
PE correction. When the intermittent double flash stops, it
means the PPEC training has finished.
Intermittent triple flash: Sidereal tracking with PEC is now
enabled.
Dec Motor Sockets: These two sockets are used to connect,
via included cable, the Dec. motor unit to the main drive hous-
ing (Figure 21).
5.2 Pinout of the Interfaces
Refer to Figure 23 on the next page,
Note:
• The SNAP port provides two trigger signals to the stereo
plug. For a camera that only needs a shutter-release
signal, either trigger signal will work. For a camera that
requires an extra “focus” signal, both signals should be
connected properly.
• The camera control cable included with the Sirius Pro
AZ/EQ-G mount is compatible with select Canon EOS
series DSLR cameras. Cables for other cameras are
optional and can be purchased separately from a dealer.
5.3 Attaching the SynScan GoTo Hand Controller
The coil cable for the SynScan hand controller has RJ-45
connectors on each end. Plug one connector into the Hand
Control port of the drive panel and the other connector into the

13
Figure 23. Schematic diagram of the drive panel port circuitry.
2
3
4
1
5
6
7
8
HAND CONTROL
GND
Vpp+
RX(3.3V)
TX(3.3V)
2
3
4
1
5
6
AUTO GUIDE
GND
RA+
RA-
DEC+
DEC-
SNAP
Optoisolator
GND
GNDV pp+
POWER
Control Signal
Internal Circuit
GND
TRIGGER
accurate), thus this is a Permanent Period Error Correction
(PPEC). A user can train the mount by guiding either manu-
ally or electronically with autoguiding. For detailed instructions,
please refer to the relevant section in the SynScan hand con-
troller instruction manual.
6.3 Batch Exposure Function
The Sirius Pro mount is equipped with two SNAP ports that
can control the shutter of two DSLR cameras (see Figure 22).
Working with the SynScan hand controller’s “Camera Control”
function, you can set the number of exposures, exposure dura-
tion, and time between exposures for up to eight different sets
of exposures. For detailed information, refer to the SynScan
hand controller instruction manual.
SUGGESTED ACCESSORIES
We also suggest these optional accessories (sold separately):
Pier Extension: Ideal for use with long-tube refractor tele-
scopes and some Cassegrains -- and for tall people! -- the
optional 6.3" Pier Extension is a must-have. It raises the fo-
cuser and eyepiece of attached telescopes to a more conve-
nient height for some configurations. Instructions and hard-
ware included.
Polar Scope: For optimal tracking and GoTo performance
the Sirius Pro AZ/EQ-G can be polar-aligned with a soft-
ware-assisted polar alignment routine that doesn't require a
polar alignment scope. But for those who prefer using a polar
scope, the optional Orion Illuminated Polar Scope for Sirius
Pro Mount is available. It's an externally mounted, "dual-hemi-
sphere" polar scope, meaning it can be used for polar align-
ment in both northern and southern hemispheres. Instructions
included.

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Power LED
SPECIFICATIONS
Product name Sirius Pro AZ/EQ-G Mount
Mount type German equatorial / altazimuth dual mode
Payload (Counterwts. excl.) 33 lbs. (15kg) (66 lbs. in two-telescope altaz mode)
Saddle type Vixen style, dual bolt clamps
Latitude adjustment range 0 - 90°
Azimuth adjustment range About ±15°
Counterweight 7.5 lbs. (~3.5kg) each (x2)
Pier Tripod 1.75-inch stainless steel legs, 12.8 lbs. (5.8kg)
Counterweight shaft 18mm Diameter, length 165mm (retractable) + 120mm extension
Power requirement DC11~16V 3A
Motors 1.8° Hybrid stepper motor
Transmission 135:1 Worm drive + 72:12 timing belt drive + 32
micro-step/1.8° stepper motor drive
Gear ratio 810
Resolution 5,184,000 Counts/rev., 0.25 arc-second
Maximum slewing speed 4.2 degrees/second
Tracking rates Sidereal, solar, lunar
Tracking modes Altazimuth or Equatorial mode
Autoguiding speeds 0.125X, 0.25X, 0.5X, 0.75X, 1X
PEC 1200 segments permanent PEC
Hand controller SynScan
Database 42,000+ objects
Celestial object catalogs Messier, NGC, IC, SAO, Caldwell, Double Star, Variable
star, Named stars, Planets
Pointing accuracy Up to 5 arc-minutes (RMS)
Resolution of aux. R.A./Dec. axis encoders 5144 Counts/rev., approx. 4.2 arc-minutes
Bubble level Built-in to mount
Weight (Tripod excluded) 17 lbs. (7.7kg)
Weight, fully assembled 44.5 lbs. (20.2kg) (EQ mode, two counterweights)
Saddle height range 41" to 48.7"
Length of pier-pod, collapsed
- with AZ/EQ head 28"
- w/o AZ/EQ head 25"
Pier extension Optional (6.3" height)
Polar scope Optional, external mount, worldwide use

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One-Year Limited Warranty
The Atlas Pro AZ/EQ-G Mount is warranted against defects in materials or workmanship for a period of
one year from the date of purchase. This warranty is for the benefit of the original retail purchaser only.
During this warranty period Orion Telescopes & Binoculars will repair or replace, at Orion’s option, any
warranted instrument that proves to be defective, provided it is returned postage paid to: Orion Warranty
Repair, 89 Hangar Way, Watsonville, CA 95076. Proof of purchase (such as a copy of the original
receipt) is required.
This warranty does not apply if, in Orion’s judgment, the instrument has been abused, mishandled, or
modified, nor does it apply to normal wear and tear. This warranty gives you specific legal rights, and
you may also have other rights, which vary from state to state. For further warranty service information,
contact: Orion Customer Service [phone]; [e-mail].
Orion Telescopes & Binoculars
89 Hangar Way, Watsonville CA 95076
Customer Support Help Line [phone] • Day or Evening
Copyright © 2015 Orion Telescopes & Binoculars