What prefix type will be used is selected form Name Parts in Main Settings tab.
Important Nikon note: Some of the Nikon models (D5000, D5100, D5200, D5300, D5500, D5600, D90, D80, D60, D40, Df) doesn't allow to use the AV dial mode without attached lens. For these models Light Auto is useless and also for Flats there is need to enable the option Advanced Bias/Flats and enter exposure duration. You can use the Shoot button the Histogram to find the right exposure. The histogram peak should be in the send section from left to right.
If you have a Nikon model that can handle AV mode without lens, in the camera menu go to section Setup -> option "Non-CPU Lenses", enter the focal length and the focal ratio of the telescope, then disable the option Advanced Bias/Flats disable the option Advanced Bias/Flats and let APT to do the automation.
Plan : Select / Create / Delete All
Here you can select for editing one of the existing plans or create a new one.
To create a new plan select from the list one of the options:
Add New Light Frames Plan
Add New Light Auto Frames Plan
Add New Dark Frames Plan
Add New Flat Frames Plan
Add New Bias Frames Plan
Add New Focusing / Framing Plan
Add New Dark Flats Plan
This will create the corresponding plan and will give possibility to edit it.
If you want to delete all plans from a type you can use one of the options
Delete All Light Frames Plan
Delete All Light Auto Frames Plan
Delete All Dark Frames Plan
Delete All Flat Frames Plan
Delete All Bias Frames Plan
Delete All Focusing / Framing Plan
Delete All Dark Flats Plan
Two confirmations are required in order to avoid mistakes. Even after them clicking on Cancel button will keep the plans.
Makes a copy of the current plan with possibility to change the type and loads the new one for editing. This is an easy way to create matching light and dark plans.
List of the defined exposures. Click on the line that you want to edit, move or delete. The parameters of the selected line are loaded in "Add / Edit Exposure" section.
Ringy Thingy is an innovative way to edit numeric values using only mouse or touch pad. See details and animation how to use it in the Application Interface notes.
Defines the duration for every exposure that will be executed by this plan line. Use a duration supported by your camera. The duration is in seconds or fraction of a second.
If you are not sure about the speeds less than a second, make a connection to the camera and check the values available in the Exp list in Camera Tab.
If the exposure duration is 0, the line will make just pause and/or will execute defined Script or Command.
Defines what ISO to use for the exposures in this plan line. Use an ISO supported by your camera. If you are not sure, make a connection to the camera and check the values available in the ISO list in Camera Tab.
Defines the lens aperture (AV) to use for the exposures taken by this line of the imaging plan. Use the option "No Change" if you don't use EOS lens or don't want to change the aperture.
The filter to use for this line of the imaging plan. Use the option "No Change" if you don't use Filter Wheel or don't want to change the filter.
In order to change filters a connection is required to the Filter Wheel during the plan execution.
If the filters are described in Filter Wheel settings tab or if there is active connection to a wheel then this list will show the filter names. In other case the list will contain only position numbers like "Filter 1", "Filter 2"...
When selected APT will wait the external script or application to finish before continuing the execution of the plan. For the internal commands APT always wait the execution to complete.
Allows controlling the plan execution order. When it is unchecked, APT will take all exposures for the first line and then will continue with the next line. When it is checked the execution order will be:
The vertical mode is useful if you want to make HDR eclipse images, or when filter wheel is used and you are not sure that weather will permit to gather all channels one after another.
Export allows to save one or more imaging plans in new file, while Import gives possibility to add saved plans in addition to the current set or overwrite all plans.
Plan Editor can be opened from 
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