Multi-camera Dithering / Synchronizing

The Guiding settings are accessible from
  Settings button in Guide section of Gear tab or with F7 shortcut.
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APT has powerful Dithering System that allows using dithering in a setup with multiple cameras. When your setup contains two or more cameras there is need APT to synchronize the moment when dithering will be made in order to be sure that none of the cameras is taking an exposure in that moment.
This is a short summary of the workflow:
Configuration (one time only)
Regular use
Here is a detailed explanation.
See Multi-Camera Operation for more information on how to use more than one camera at the same time.
Once you have started the different APT instances you have to setup a Client/Server configuration. In the instance that controls the main camera use click on the Settings button in Guide section of Gear tab (or use F7 shortcut) to open the dithering settings dialog and select from the list Multi-Camera Dithering the option “Server Mode”. After that from the list Multi-Camera Sync select the synchronization mode. Available are two modes – “Strict” and “Loose”. In the first mode all clients and the server will make an exposure and then will wait the server to make dithering before continuing with the next exposure. In “Loose” mode, if a client APT is taking shorter exposures than the server and if there is enough time then, the client will start new exposure. For example if the server is taking 10 minutes exposure the client has time to make several 2 minutes exposures without waiting the dithering action.
The server defines the all parameters for the dithering like program, distance, timeout and etc.
Once server is configured, next are the clients. In the other APT instances select from Multi-Camera Dithering the option “Client mode”. With this configuration is finished. There is no limitation for the number of the clients, but the server can be only one.
The most common workflow is to connect the cameras in all APT instances and to select the plans that will be executed. After that to start the clients first and the server last. This order allows the Dithering System to synchronize the exposures from the first one.
If the server is started first then all clients be put in SYNC state till server finish the exposure that is in progress.
The clients <-> server connections and the server <-> guiding program connection are checked and initialized (if there is need) on every plan start. So you don't need to take any additional actions.
Tips&Tricks If you want to monitor closer the work of the Dithering System use Ctrl+Click on Settings button in Guide section of Gear tab (or F8 shortcut) to open the Dithering System Monitor. There you can see the status of the system in current APT instance. The server monitor can show the status of up to 10 clients.
Tips&Tricks If you don't need dithering you can still use the Dithering System to synchronize the exposures by disabling the Auto-Dithering.