This dialog box allows you to set options for controlling which gain references are used in various cases where multiple references are available. Multiple references can be useful when the quadrant correction for a 4-port camera is imperfect, or if there or problems with fixed pattern noise in binned images even after adjusting the BinningOffset properties. Between the ability to make references in SerialEM for higher binnings, and the ability to pick between these references and DigitalMicrograph (DM) references for individual binnings, it should be possible to control these problems.
The default behavior of the program is: 1) If both unbinned and binned by 2 SerialEM references exist, then the unbinned reference is used for all odd binnings, and the binned by 2 reference is used for even binnings, but only if it is newer than the unbinned reference. 2) If the DM reference is newer than the SerialEM reference, then the program will ask once whether you wish to use it instead; it will ask this question separately with regard to the unbinned and binned by 2 SerialEM reference.
Once the 'ExtraGainReference' property is set for a camera, this behavior is modified. For each binning where an extra reference is allowed, the program will use that reference if it exists, regardless of its age. If it does not exist, the program will use the unbinned or binned by 2 reference as just described. If a reference does exist but is older than the DM reference, then it will ask about whether you want to use the DM reference instead, specifically for that binning.
Note that whenever you leave this dialog by pressing 'OK' instead of 'Cancel', the program re-initializes the gain reference module and it will ask the questions about DM references all over again.
Do not use references with binning higher than 2
With this option selected, the program will not only ignore any existing references for binnings greater than 2, it will also behave the same is if such references were not allowed. It will not ask about using a DM reference specifically for such binnings.
Use binned by 2 reference even if older than unbinned reference
Select this option if you always want to use a binned by 2 reference if available, even if it is older than the unbinned reference. If you find that you generally need a separate reference for binned by 2 and unbinned images, you would use this option to avoid having to keep track of which one was done first.
Choosing DigitalMicrograph instead of SerialEM reference
These choices control the questions about whether to use a DM reference.