1. Take a full image at any supported binning (with "Take One"). Make sure "Use subframe" in the frame and focus module is not checked.
  2. Now, Check "Use subframe" in the frame and focus module.
  3. Draw a rectangle onto the image you just took. This rectangle is now saved as the subframe area.
  4. Now clicking "Take One" or "Start" (with "Use subframe" checked) will use the subframe.  Unchecking "Use subframe" will begin full frame exposures again. While capturing subframes you can switch between binning modes without losing track of the area you selected.


Notes:  

  1. Taking a new frame and focus frame at a binning level different from the one at which the subframe area was selected, it will be removed.  You will need to reselect the area using the new frame.
  2. You are free to rotate images when using the subframe option.
  3. When "use subframe" is checked, you will only be able to draw subframe selection areas on "frame and focus" type frames (i.e. not on your light frame or others).