Use these settings to specify what kind of telescope hardware you have, and how SkySafari should communicate with your telescope.
In order to communicate with your telescope, you will need either:
- SkyFi - a Wi-Fi adapter that relays wireless communication from your mobile device to the serial port on your telescope. Android devices must support Ad Hoc Wi-Fi networks to use our SkyFi wireless adapter; most do not. All iOS devices support Ad Hoc Wi-Fi, and therefore can use SkyFi.
- SkyWire - a serial cable accessory for iOS devices. This connects your iPhone/iPad/iPod Touch to the serial port on your telescope using a direct cable connection. Does not work with Android devices.
- a bluetooth serial adapter, which relays communication from SkySafari through your Android's bluetooth radio hardware to your telescope's serial port. Does not work with iOS devices.
- a Celestron WiFi scope using either its built-in WiFi or Celestron's SkyQ Link. Note that when using a Celestron WiFi scope, the telescope setup and control interface will be somewhat different. This is detailed more below.
You can also use our SkySafari software, running on a Mac OS X computer with Wi-Fi and a serial port, as a Wi-Fi-to-serial server. See Simulation Curriculum's web site at www.skysafariastronomy.com for more details.
Scope Type - selects the type of telescope you want to control. SkySafari can control any of the telescopes in the list. SkySafari supports many encoder systems that can read out the telescope position but not actually move the telescope. The Celestron AstroMaster and JMI NGC-MAX are examples of such encoder systems.
Mount Type - selects your telescope's type of mounting:
Equatorial Push-To - a non-motorized mount whose right ascension axis is pointed at the celestial pole. The mount must be manually turned around this axis to follow the diurnal motion of the sky.
Equatorial GoTo (Fork) - a motorized equatorial mount that automatically follows the diurnal motion of, and can automatically slew to, targets in any part of the sky. Has one or two fork arms that suspend the telescope between them. The Meade LX-200 and Celestron NexStar (when used with an equatorial wedge) are examples.
Equatorial GoTo (German) - a motorized, polar-aligned mount that requires reversing the telescope tube to the east or west side of the mount when the telescope passes through the meridian. Examples include the Losmandy and Takahashi mounts.
Alt-Az. Push-To on Equ. Platform - a non-motorized mount that must be manually pushed to targets in different parts of the sky. However, it sits on a motorized platform that is aligned with the Earth's polar axis, so the mount follows the diurnal motion of the sky when it is not being pushed.
Alt-Az. Push-To - a non-motorized alt-azimuth platform with fork arms that suspend the telescope between them. It is moved manually by pushing the telescope tube. It sits flat on the ground, so its "up-down" and "left-right" axes of motion align to the local horizon and zenith. This includes most Dobsonian telescopes.
Alt-Az. GoTo - a motorized alt-azimuth platform with fork arms that suspend the telescope between them, and can slew to any set of coordinates in the sky on command. Includes the Meade LX-200 and Celestron NexStar when used in the alt-azimuth configuration.
If your telescope mount has encoders which provide a digital readout of the scope's position, additional text fields will appear here. These let you specify the encoder resolution.
RA/Azm - The number of steps per revolution for the encoder attached to the telescope's Right Ascension axis (or Azimuth axis, if you have an alt-azimuth mount).
Dec/Alt - The number of steps per revolution for the encoder attached to the telescope's Declination axis (or Altitude axis, if you have an alt-azimuth mount).
Get Automatically - If turned on, SkySafari will attempt to read these values from your encoders when it connects to the telescope controller. If turned off, you can enter the encoder steps per revolution manually; then SkySafari will send the values you entered to the encoders when connecting to the telescope. You can do this if (for example) your mount is using gears or pulleys to increase the effective encoder resolution.
Depending how your encoders are installed, their position readouts may increase when they are turned clockwise, or increase when they are turned counterclockwise. If the encoder position readouts increase when they are turned counterclockwise, enter a negative value for the number of steps per revolution. You may need to determine the correct + or - sign by trial-and-error. If you push your telescope left (or up), but the telescope field-of-view indicator on the sky char moves right (or down), the sign is probably wrong.
If you are using SkySafari with SkyWire connected to your iPhone, iPad, or iPad Touch, then SkySafari will use SkyWire (rather than Wi-Fi) to communicate with your telescope.
If you are using SkySafari for Android, then the first two settings below determine how SkySafari communicates with your telescope - either via Bluetooth or Wi-Fi. These settings are not present in the iOS version of SkySafari.
Connect via Bluetooth - If selected, SkySafari will only attempt to communicate with your telescope using a bluetooth serial adapter. The adapter must be turned on, physically connected to your telescope's serial port, and paired with your Android device.
Connect via Wi-Fi - If selected, SkySafari will only attempt to communicate with your telescope using a Wi-Fi adapter like SkyFi. The adapter must be turned on, and physically connected to your telescope's serial port.
If you are using Wi-Fi, then the following settings must be correct. These are only used with Wi-Fi telescope communication. They will be disabled if you are communicating via bluetooth, and ignored if you are using SkyWire with an iOS device.
- Auto-Detect SkyFi - Detects your SkyFi unit's IP address automatically, using the name you have configured for your SkyFi. This requires SkyFi firmware version 2.3 or later!
- SkyFi Name - The name of the SkyFi device whose IP address you want SkySafari to automatically detect. This requires SkyFi firmware version 2.3 or later. Make sure to enter the same name here as you entered into your SkyFi unit's configuration web page!
- IP Address - If you do not auto-detect your SkyFi's IP address, you can enter it here manually instead. If you are using a Wi-Fi device that does not respond to SkyFi auto-detection, you must enter its IP address manually. Your mobile device must be on the same Wi-Fi network as the SkyFi, and must have an IP address on the same subnet. Check your iOS or Android's Wi-Fi network settings to make sure this is correct.
- Port Number - The TCP port number to be used for communication with the adapter. Make sure this is the same TCP port that the telescope adapter or server is listening on.
- SkyFi Settings Web Page - If you have a SkyFi wireless adapter, this item displays its settings/configuration web page. You must be connected to SkyFi's wireless network in order to see this web page.
Celestron WiFi Telescope Settings
If you have chosen Celestron WiFi as your telescope type, the Communications Settings section described above will not be present. Instead you will see choices for Setup and Control and for Communication. The Setup and Control screen will have options that vary depending upon the exact Celestron WiFi scope you are connected to. The Communication screen will allow you to change whether you connect to the WiFi directly or by using access point mode where the WiFi scope has joined your local network.
Set Time and Location - If turned on, SkySafari will send the time and location from your mobile device to the telescope when establishing a connection. This will overwrite your telescope's previously-set time and location. For some telescopes, this may invalidate your alignment. For older Meade LX-200 telescopes, this may also cause a delay of up to 15 seconds when connecting.
Note: This option is disabled with Celestron WiFi scopes. The time and location is always sent in this case.
Readout Rate - The readout rate is how often SkySafari requests the telescope's position from the mount. If you set this rate to "4 per second", then SkySafari will request the telescope's position (and update it on screen) four times every second.
If the telescope communication drops often, the rate of position requests may be too high for the telescope to respond properly. Setting a lower rate of 1 or 2 readouts per second may improve reliability. The best readout rate may require some trial and error to find. A lower readout rate will update the telescope's position in the sky chart less frequently, and may make SkySafari's telescope controls feel sluggish.
Save Log File - If turned on, SkySafari saves a log of its communication with the telescope on your mobile device. SkySafari creates a new log file every time you connect to the telescope. The log file records every command that SkySafari sends to the telescope, and every response from the telescope. The log file name contains the date and time you began the telescope session, for example:
This log file can be emailed to Simulation Curriculum for troubleshooting telescope communication problems. You can transfer the telescope communication log from your iOS or Android device using iTunes file sharing (iOS) or SD file card transfer (Android).
iOS users - transfer the scope communication log to your computer with iTunes file sharing. Connect your iPhone or iPad to a computer running iTunes with a USB cable. Select your iOS device when it appears in iTunes, then find the "Apps" section. Choose SkySafari Plus or Pro from the list of apps. iTunes will then display the SkySafari Documents that can be shared with iTunes.
Android users - the scope communication log is written to a folder named "SkySafari Plus" or "SkySafari Pro" at the top level of your SD card. Copy this file to your computer with a USB cable, or simply email it to yourself.