Vcurve

You must characterize your system before you can perform an autofocus run with FocusMax. These parameters are unique to your system and you first need to measure them.

Vcurve box:

End Points will allow you to manually specify the Vcurve Initial and Final focuser position

Half Width will allow you to enter the Center focuser position and Half Width which is the focuser move range on each side of focus

Move Increment is the number of steps to be taken for each Vcurve position

Number of Moves is the total number of moves that will be taken to generate the Vcurve

Repeat setting will rerun the Vcurve when it has completed the measurement process

Images / Position is the number of images that will be taken at each Vcurve focuser position which will be averaged. This will help smooth the Vcurve by reducing the influence of varying seeing conditions.

Vcurve plot:

Displays the shape of the Vcurve from the run.

Fit box:

Left & Right Slopes are shown

Position is the focuser point in which Left & Right lines cross the x-axis. Note that the minima of the Vcurve is the focus position and that it does not touch the X-axis

Difference is the Position INtercept Difference or PID which is the difference in position between the Right & Left lines intersect the x-axis.

The First Light Wizard tutorial which will describe how to automate the Vcurve generation process.

The Running Vcurve tutorial which will describe how to manually generate a Vcurve.

File / Open

Allows you to load a previously generated Vcurve from disk to be inspected or shared with other users.

The path to these files can be found in Preferences / General