----- Original Message ----- From: "Nave, C (Colin)" <[EMAIL PROTECTED]>
> Several have raised the issue of radiation damage. The strategy which > Bob mentions can make sense, ensuring fresh parts of the crystal are > regularly brought in to the beam. I would have thought 5-10 micron beams > were rather too small if your crystal is several times bigger than this. > I think the microbeams can overcook the samples, particularly when > collecting large rotation ranges. The centre part of the crystal (if > centred!) is constantly in the beam in this case. On the other hand, why perfectly centre the crystal? A set-up where a narrow beam runs past rather than through the rotation axis will spare the central voxel entirely; apart from a somewhat more often exposed doughnut around the axis, only fresh parts of the crystal are illuminated that way. Sebastiaan Werten.
