Equinox Systems GEMINI Manuel d'utilisateur

Users Manual Level 4 René Görlich, Michael Rudolph, and Dave Sandage April 2006

Gemini Users Manual 5 startup or pre-determined Home position, and (4) initiate a meridian flip if possible. A focusing feature is also availabl

Gemini Users Manual 95 |||Store Model #<n> |||Reload Model #<n> |Encoder ||EncRes RA ||EncRes DEC ||Test Encoder ||Use/Ignore Encoder

Gemini Users Manual 96 ||Sync or Align |||Sync only |||Sync ↔Add.Al. QuickMenu {Focusing} (only available if focuser board connected) Fo

Gemini Users Manual 97 8.2 Catalogs Level 4 software contains • 8290 objects of the New General Catalog (NGC) • 5437 objects of the Index Cat

Gemini Users Manual 98 8.3 Alignment Star List Although Gemini can perform an alignment or sync operation on any object, it is often most conve

Gemini Users Manual 99 Antares α Sco Sco Alpha 21 16h29.4m -26°25'55” 1.0 Kornephoros β Her Her Beta 27 16h30.2m +21°29'23”

Gemini Users Manual 100 8.4 Serial Line Protocol The Gemini system supports a subset of the Meade®2 LX200 Command Set making it compatible with

Gemini Users Manual 101 <object name># returned if the mount is not aligned or no object was selected, otherwise the name of the selected

Gemini Users Manual 102 Signed degrees (-90 to +90), minutes, seconds. The degree sign in Low Precision mode is the character 0xDF. :GE# <hh&

Gemini Users Manual 103 Hours (0 to 24), minutes, seconds or tenth of minutes. :GS# <hh>:<mm>:<ss># Sidereal Time. From L4, V

Gemini Users Manual 104 the counterweight pointing downwards (CWD position). From L4, V1.0 up. :hN# Sleep Telescope: stop tracking, blank displ

Gemini Users Manual 6 1.3.6 Redesigned Quick Menu selection To accelerate the Quick Menu access and to offer more selections, the Quick Menu fea

Gemini Users Manual 105 :Ml# # Move Unlock: Slew commands :MS# and :MA# will be executed again. :Mf# 0 1Object below horizon.# 3Manual Control.

Gemini Users Manual 106 must not exceed 255 or will be cut off modulo 256. :Mi<direction><steps># Moves into <direction> &quo

Gemini Users Manual 107 :Od<object line># Download a User Catalog entry to the Gemini. The object line consist of • the object name (up

Gemini Users Manual 108 transferred to the Gemini refer to the standard epoch J2000.0. Refraction is calculated. From L4, V1.0 up. Precision :

Gemini Users Manual 109 :Sz# command has been sent prior. If the coordinate selection is valid the object status is set to "Selected".

Gemini Users Manual 110 :SN<name string># 1 Set name of the second site stored. :SO<name string># 1 Set name of the third site st

Gemini Users Manual 111 Gemini Native Commands Many of Gemini’s system settings that cannot be accessed using the LX200-like command set can be

Gemini Users Manual 112 Id Get Parameters Set Parameters Get Return Values Description and Remarks product of worm gear ratio, spur gear ratio a

Gemini Users Manual 113 Id Get Parameters Set Parameters Get Return Values Description and Remarks maximum step count, not for setting it). Note

Gemini Users Manual 114 Id Get Parameters Set Parameters Get Return Values Description and Remarks 130, 131..137 131: Sidereal 132: King Rate

Gemini Users Manual 7 Additionally, a second submenu item "Reset to Defaults" was introduced there to allow you to reset only the Safe

Gemini Users Manual 115 Id Get Parameters Set Parameters Get Return Values Description and Remarks NP (Axes Non-Perpendicularity at the Pole), i

Gemini Users Manual 116 Id Get Parameters Set Parameters Get Return Values Description and Remarks western safety limits currently set. NOTE: Ge

Gemini Users Manual 117 Id Get Parameters Set Parameters Get Return Values Description and Remarks position. GoTo operations will include a meri

Gemini Users Manual 118 Id Get Parameters Set Parameters Get Return Values Description and Remarks 311 0..15 0..63 Feature Port Status. 4 bi

Gemini Users Manual 119 Id Get Parameters Set Parameters Get Return Values Description and Remarks the DEC divisor referred to the number of RA

Gemini Users Manual 120 Id Get Parameters Set Parameters Get Return Values Description and Remarks maximum is the product of RA motor encoder re

Gemini Users Manual 121 Id Get Parameters Set Parameters Get Return Values Description and Remarks to user defined values, f.i. to allow multipl

Gemini Users Manual 122 Id Get Parameters Set Parameters Get Return Values Description and Remarks 0 to PECmax-1. [repeat count] indicates the n

Gemini Users Manual 123 Using the native commands: • The Identification tag is interpreted as an integer value, leading zeros are ignored. •

Gemini Users Manual 124 8.5 Serial Communications A graphical representation of the Gemini Serial socket is pictured left (i.e. Pin D is close

Gemini Users Manual 8 2 Getting Started Now that you’ve unpacked your Gemini unit, you are no doubt eager to start using it. Please take some

Gemini Users Manual 125 8.6 Autoguider Port IMPORTANT: There are two different versions of the Gemini Autoguider port hardware. The version

Gemini Users Manual 126 To connect cameras with TTL output, you will need the following: • SBIG Relay Adapter Box cable (diagram at http://www.s

Gemini Users Manual 127 8.7 Encoder Port The Gemini encoder port is compatible with the “Y” cable typically used with many encoders such the

Gemini Users Manual 128 Connecting End Switches As mentioned above, the 4 lines of the encoder port can be used to implement physical end switch

Gemini Users Manual 129 8.8 Feature Port The Gemini Feature Port allows hardware designers to add additional functionality to Gemini that can

Gemini Users Manual 130 8.9 Motor Connector Pinouts RJ-45 Connector DIN Connector Either flat or twisted pair cables can be

Gemini Users Manual 131 8.10 Power Connector Pinout Power Connector

Gemini Users Manual 132 8.11 Upgrading the EPROM The software for the Gemini system is programmed into an EPROM that resides in the electronics

Gemini Users Manual 9 o Display will confirm the object to which you are pointing o Press RA+ to complete the initial alignment • For each of

Gemini Users Manual 10 2.2.3 Encoders Gemini can take advantage of optional encoders on your mount. Plug the encoder cable into the 8-pin socke

Gemini Users Manual 11 2.2.4 Power Requirements The Gemini System requires 12–18 Volts DC, 3 Amps to operate. You will need to have a battery o

Gemini Users Manual 12 moving in declination, the direction does NOT change as the mount crosses the celestial pole. Menu Mode: Press the MENU bu

Gemini Users Manual 13 2.3.3 QuickMenu If you press and hold the MENU button for at least one second, a selection of useful menu items such as C

Gemini Users Manual 14 Centering Speed, after another 2 seconds to ½ Centering Speed, and finally to full Centering Speed. Pressing the opposite

Copyright © 2002-2006 by René Görlich Gemini Users Manual i Table of Contents 1 Introduction...

Gemini Users Manual 15 fair amount of misalignment in a GoTo operation (using the modeling parameters) and when tracking (using Closed Loop track

Gemini Users Manual 16 message scroll across the display (pressing the MENU button terminates the message). When powering up the unit for the fi

Gemini Users Manual 17 Each item will be displayed for a few seconds before going to the next one. If you want to change the currently displayed

Gemini Users Manual 18 2.4.2.2 Completing Startup After the system has completed its startup tasks, it will display the UTC Date/Time, Mount Typ

Gemini Users Manual 19 Type. If you alter either the Mount Type or hemisphere, restart the Gemini after completing the Setup operation. Simply t

Gemini Users Manual 20 Make sure that you are certain of the identification of all stars that you use for alignment. If you misidentify a star

Gemini Users Manual 21 confirm the object to which you are pointing by displaying its name. Press RA+ to complete this alignment. Repeat the pr

Gemini Users Manual 22 2.4.4 Normal Operation By now, you are no doubt eager to put Gemini through its paces. You can control your mount using

Gemini Users Manual 23 “Setup→Communication→Coordinate Epoch→Epoch J2000.0” menu item. You can find more details on this in chapter 5. Alternat

Gemini Users Manual 24 3 Important Concepts about Your Mount In order to get the most from your mount and the Gemini system, you’ll need to und

Gemini Users Manual ii 3.3 Tracking ... 26

Gemini Users Manual 25 Gemini displays RA in hours, minutes, and decimal minutes so that the RA value above would be represented as 16h 42m9. De

Gemini Users Manual 26 3.2 How the Sky Moves If you have spent any length of time outdoors looking at the stars, you’ve probably noticed that ev

Gemini Users Manual 27 3.3.1.1 Predefined Rates Two predefined tracking rates drive the RA axis at a constant speed to compensate for the Earth’

Gemini Users Manual 28 vice-versa. You can reselect the lunar tracking rate periodically throughout the observing session to allow Gemini to rec

Gemini Users Manual 29 coordinates do not match, Gemini makes slow corrections in both RA and Dec. axes to point the telescope back at the object

Gemini Users Manual 30 Training Comet Tracking When you select “Setup→Mount Parameter→Tracking Speed→Comet Tracking→Train Tracking,” a training

Gemini Users Manual 31 RA Rate Gemini uses a 1.5 MHz timer to regulate the tracking rate in RA. The number that you enter as the RA rate diviso

Gemini Users Manual 32 Defined Tracking" (to be used instead of a training phase) is useful for tracking minor planets and comets by setting

Gemini Users Manual 33 outside the allowed range. Use the Hand Controller to carefully move beyond the old limit to the new limit position, and

Gemini Users Manual 34 To solve this problem, Gemini now allows you to set a “GoTo Limit” to define a point past which Gemini will always GoTo th

Gemini Users Manual iii 5.4.3 Reduced Menu / Full Menu ... 77 5.4.4 Centering...

Gemini Users Manual 35 with some type of reticle, and watching for the star to drift north or south as the mount tracks in RA. Depending on wher

Gemini Users Manual 36 button to slew back and forth between the two stars. When you are finished, press the MENU button once more, and when the

Gemini Users Manual 37 especially for longer exposures. It is recommended that you use one of the polar alignment methods above to achieve the b

Gemini Users Manual 38 • Cold Start • Warm Start • Warm Restart When the Gemini is powered up for the first time or after a CMOS reset, "

Gemini Users Manual 39 on, and Cold Started again. This does not apply to geographic coordinates or UTC Date/Time that are changed when prompted

Gemini Users Manual 40 4 Considerations for Imaging The Gemini system has many features that make it especially suitable as an imaging platform

Gemini Users Manual 41 version does not directly support autoguiders with TTL output, but the newer version does. Gemini contains a separate Aut

Gemini Users Manual 42 4.2.3.2 Connecting an Autoguider with TTL Output The typical "open collector" output stage (e.g. the ST-7/8/9/

Gemini Users Manual 43 4.3 Periodic Error Control (PEC) 4.3.1 What is Periodic Error? The Gemini servomotor on the RA axis turns a worm that me

Gemini Users Manual 44 4.3.2 The PEC Submenu The PEC submenu (“Setup → Mount Parameters → PEC”) has these options: • Train PEC • Clear Data •

Gemini Users Manual iv 8.4 Serial Line Protocol ... 100 8.5 Se

Gemini Users Manual 45 4.3.2.2 Clear Data Selecting this menu item clears both PEC data sets and disables PEC correction. This is useful if the

Gemini Users Manual 46 The following table lists the number of steps per second (sidereal tracking) for several mounts: Worm Period Steps per s

Gemini Users Manual 47 “Drift Correction” function if you want to use the PEC in a region of the sky other than the one where you trained it, or

Gemini Users Manual 48 If the averaging function is not used, newly trained data simply replaces the previous training run in the current data se

Gemini Users Manual 49 5 Gemini Command Menu Reference The Gemini Menu system consists of a tree of menus and submenus displayed on the Hand Co

Gemini Users Manual 50 then centered in the telescope's field of view and "Synchronize" is executed. This constitutes the initial

Gemini Users Manual 51 • {GoTo <object>} • Coordinates • Identify The Reduced Main Menu is restored to the Full Main Menu using the Qui

Gemini Users Manual 52 Select "Align Telescope→GoTo Bright Star" to display a list of bright stars currently above the horizon. Scrol

Gemini Users Manual 53 The difference between the position Gemini pointed to when you did the "GoTo" operation and the one you moved to

Gemini Users Manual 54 correction) allows you to polar align your mount with fairly high accuracy by taking advantage of the pointing model that

Gemini Users Manual 1 1 Introduction 1.1 General Description The Gemini Astronomical Positioning System is a professional level computerized d

Gemini Users Manual 55 Once the position of the selected object is calculated, additional data related to the object can be displayed using the &

Gemini Users Manual 56 5.3.2.6 IC (Index Catalog) There are 5437 objects stored in this catalog, among which are nebulae, galaxies and clusters.

Gemini Users Manual 57 catalog subset, the next available object with higher designation is displayed. You can scroll through all of the availabl

Gemini Users Manual 58 5.3.3 Show Information This menu item allows you to scroll through Gemini's information buffer. Pressing the RA+ bu

Gemini Users Manual 59 • {GoTo Bookmark #n} 5.3.6.1 RA/DEC Display Upon selecting "RA/DEC Display," Gemini switches to the Telescope

Gemini Users Manual 60 Note: See section “2.3.4 Moving the Mount Manually” of this manual for how the telescope’s movement speed depends upon th

Gemini Users Manual 61 Magnitudes NonStellar Obj. Magnitudes <14m0 • Messier Objects Planetaries/SNR Magnitudes <13m0 Object Types

Gemini Users Manual 62 If one of the FOVs is selected, the telescope moves in alternating, increasing movements around the starting position in b

Gemini Users Manual 63 5.3.9.3 Civil Time (Local Civil Time) Expressed in 24 hour format, local "Civil Time" is converted to GMT (or U

Gemini Users Manual 64 5.3.10.1 Hand Controller • Visual Mode: C-S • Photo Mode: G-C • All Speeds: G-C-S This menu item contains three modes

Gemini Users Manual 2 1.2 Features 1.2.1 Physical Features The Gemini Astronomical Positioning System is a professional level computer-to-servo

Gemini Users Manual 65 5.3.10.2.1 Tracking Speed This menu item allows you to set the speed and method used to track objects in the sky. You ca

Gemini Users Manual 66 corrections. Although an object can usually be kept centered using this technique, field rotation occurs if there is pola

Gemini Users Manual 67 happen. You can select a value between 0 and 255, which is the number of steps made at high speed whenever the Dec. direc

Gemini Users Manual 68 DEC Spur: DEC Worm: RA M. Enc: DEC M. Enc: In addition to using the Setup command, you are able to change the Mou

Gemini Users Manual 69 be mounted, and the accessory equipment that may be attached. The default safety limits are 114 degrees when the telescop

Gemini Users Manual 70 For example, setting the GoTo limit to 95 degrees means that a GoTo command to any object 5 degrees or further west of the

Gemini Users Manual 71 5.3.10.3 Encoder • EncRes RA • EncRes DEC • Test Encoder • Use/Ignore Encoder • Use/Ign End Switches Without optiona

Gemini Users Manual 72 These functions allow you to use the Gemini as an alarm timer and to control the safety limit buzzer. The time for sound

Gemini Users Manual 73 5.3.10.7 Restore Defaults • Losmandy • Mountain Instr. Executing this menu item allows you to do a CMOS reset, restorin

Gemini Users Manual 74 From the sign of the latitude, Gemini knows the hemisphere; northern latitudes are "plus," and southern latitude

Gemini Users Manual 3 (f) Restore Default Function The user can restore all setup items to their default Losmandy or Mountain Instruments values.

Gemini Users Manual 75 to change. The selected character will blink. Use the DEC+ and DEC- keys to scroll through the possible characters for t

Gemini Users Manual 76 Note: The “Sync or Align” commands are used only to modify the behavior of the serial line commands and do not in any way

Gemini Users Manual 77 IMPORTANT: Once QuickMenu is accessed and begins to scroll, entering one of its menu items is unavoidable. For this reas

Gemini Users Manual 78 5.4.5 Park Mount! • Exit w/o Change • Park @CWD pos! • Park @Home pos! • Stop Tracking! The CWD (counterweight down)

Gemini Users Manual 79 This menu presents itself immediately after a "Cold Start" as a convenient alternative for changing previously s

Gemini Users Manual 80 6 Serial Communication Gemini supports two serial ports. The first one is available to the user via the RJ22 RS-232 sock

Gemini Users Manual 81 The following picture shows a cable to connect the Gemini to a PC equipped with a DB9 serial COM port (The locking tab of

Gemini Users Manual 82 negative power terminals should be connected with low resistance wire. Alternatively, electrically isolated power supplie

Gemini Users Manual 83 internal micro controller with 5V TTL signals, an adapter is necessary to use it to communicate with RS232 ports. Adapter

Gemini Users Manual 84 6.3.2 Gemini Native Commands Access to the Setup data, modeling parameters, tracking rates and much more is possible by m

Gemini Users Manual 4 the setup menu. When a GoTo operation occurs, the telescope moves at GoTo Speed, and then slows down to Centering Speed as

Gemini Users Manual 85 Once you have connected your GPS receiver to Gemini, you should configure your GPS to output either Garmin Textout protoc

Gemini Users Manual 86 6.5.4 Coordinate Precision Both LX200 coordinate modes, low and high precision, are supported. After a CMOS reset or the

Gemini Users Manual 87 7 Troubleshooting 7.1 Common Error Cases 7.1.1 Gemini Does Not Start • If the power LED is off, the display stays bla

Gemini Users Manual 88 play than others. The RA worm gear can have somewhat more play than the Dec., but it should not be more than necessary. •

Gemini Users Manual 89 7.1.7 GoTo Position is Completely Wrong • UTC Date/Time, Mount Type and Geographic Location must be set correctly. Be s

Gemini Users Manual 90 • If this happens immediately after start-up, limits may be incorrectly set. Cold start the mount, and check the limits.

Gemini Users Manual 91 the “Setup” menu to set all of the appropriate settings for your mount (see chapter 2). If the problem persists, contact

Gemini Users Manual 92 8 Appendices 8.1 Gemini Menus Align Telescope |GoTo Bright Star |{Reset Alignment} |{Additional Align} |Synchronize |{

Gemini Users Manual 93 |||Arbitrary Obj. (submenu for all kinds of objects) |||Stellar Objects |||NonStellar Obj. |||Planetaries/SNR |||Galaxie

Gemini Users Manual 94 |||Comet Tracking ||||Train Tracking ||||Calculate Rates |||||1st RA/DEC pos., 2nd RA/DEC pos., Hours ||||Enter RA Rate ||