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• normal sase (not many beam-related fluctuations): take sqrt of number shots and use that many groups (beat down background noise with lots of averaging).   Tim suggests perhaps a maximum of 100 groups.
• slotted foil (many beam-related of fluctuations): restrict it to 5-10 images per group, make as many groups as possible using typically 30 seconds to a minute of data at 60Hz.
• split undulator, single bunch, head and tail lase in separate sections of the split undulator: Ryan expects this to be chaotic like the slotted-foil
• two electron bunch, two color (typically uses slotted-foil): chaotic like slotted foil

• seeded beam: For any results, I would use the SASE settings. However, note that reconstruction for seeding is a little ambiguous. The beam first seeds, so is partly spoiled before seeding itself in the second stage. Therefore it isn't clear exactly with one lasing off reference which part lased more for the seeded part. It is similar to the case when one bunch is used to make two pulses with the split undulator. However, if seeding amplification was strong and intense, this may be enough.

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