On completing an experiment, in certain cases it can be useful to collect some extra data. Providing the crystal has not been removed from the diffractometer, frames can be added to the existing data set. This option is particularly useful in cases where a crystal is unexpectedly non-centrosymmetric, and the original strategy was calculated so that the Friedel pairs were considered to be equivalent. In order to obtain a complete data set (to publish such data), it may be necessary to collect more of the Friedel pairs.
On completing the experiment, click on the Start/Stop button and choose Append data collection.
Select the run list used for the experiment that is to be appended (*.run file).
In the resulting strategy window, select the Advanced button and make sure the Lock State says Locked. This means that the frames already collected are still part of the strategy but are considered done and locked. Any new strategy calculation will take these into account, and then add any necessary frames.
The user can then change the strategy details to collect more data, either by increasing the resolution, redundancy, or by changing the coverage.
Click Calculate new strategy. The software will then provide the user with a suitable experiment to collect the extra data required.
If further changes are required, Undo Strategy must be selected before the extra changes are applied (and Calculate new strategy selected). This avoids overwriting the previously collected data.
Click Start Experiment to collect the extra frames.
cited from crysAlispro manual
