The filter wheel settings tab contains options related to filter wheel. Here you can enter the filter names and focus offset for the filters mounted into your wheel. Describing the names here allows APT to show them in the Plan Editor and in the Camera tab (the selected plan table) rather than using the filter position number. This tab is required for SBIG and manual wheels, but it will be more comfortable for you if you enter the information even if you use ASCOM / INDIGO / INDIcompatible wheel.
Note that if there are values in this tab APT will ignore the values entered in the properties of the ASCOM driver.
Defines the focus offset that you want to apply when this filter is selected. Not all filters are para-focal, so if you measure the exact difference in the focus between the filters (in steps of your focuser) it can save you the refocusing on every filter change. To use this feature you need Focuser connection and enabled "Adjust Focuser" in Filter Wheel section of Gear tab.
The value 0 means that there is no offset.
If you are using two focusers you can define two offsets separating them with semicolon (;). For example 10;3 means that the R filter has 10 focuser steps offset from L via main focuser and 3 steps via the second focuser allowing the Off-Axis-Guider to remain sharp.
Note: The focus offset has not thing with the black level/offset.
Defines the gain value that you want to apply when this filter is selected. Empty value means that gain value should not be changed. This value will be used with priority during imaging plan. During LiveView or Shoot image if the Gain value in Camera tab is not empty it will be used with priority.
Defines what exposure duration to be used for every filter during the Auto-Focus Aid process. If the value is empty the next option is used. The priority from top to lower is:
Defines what exposure duration to be used for every filter during the GoTo++ Plate Solving process. If the value is empty the next option is used. The priority from top to lower is:
Allows usage of manual filter wheel or filter drawer. Enable this option, enter the installed filters names (and offsets), then click on Connect Wheel button in the Gear tab. The main purpose of this feature is to add the right filter name prefix in the image filenames for easier processing. It also can be used to adjust the focuser position on filter change using the entered offset.
When this option is enabled, APT will show dialog box every time there is need to change the filer of manual filter wheel or drawer during plan execution. Clicking on OK will resume the imaging.
Note: Give few seconds the guiding to settle after filter change.
When this option is enabled, on plan start APT will check if that plan is configured to use filters and will warn if there is no active connection to a filter wheel.
The APT Settings dialog box is accessible from 
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