You can use grid scans to automatically centre your sample. This method is very successful with well frozen (ice-free) crystals mounted in clean loops.
To enable X-ray Centring, please open the 'User Options' and click the last option labelled 'HT X-Ray Centring (5 min/sample)' before you load the (first) sample you want to centre. Additionally, the second option 'Use OAV Centring after Keyence Centring' needs to be ticked, which is the default.
Please specify your data collection parameters in the data collection table, as the data collection currently starts immediately after X-ray Centring.
If you now load your sample, the routine puts the loop at the cross-hairs (Keyence Centring), performs the OAV centring and then automatically carries out a two-dimensional grid scan. Afterwards, a finer, linear grid scan is performed perpendicularly to the two-dimensional one at the position where the crystal diffracts best. Then, the data collection is automatically started. The whole process from loading the sample to the end of a 360 degree data collection with standard parameters takes approximately 3.5 min.
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