I agree - looks like small molecular diffraction. Try increasing delta-phi to catch more of the lattice to confirm - I often do a 5º image or two with the detector pushed as close as possible to check for salt diffraction when screening.
The lack of low res (~15-20Å) spots around the beamstop is another "smoking gun". HTH Dave ============================ David C. Briggs PhD Father, Structural Biologist and Sceptic ============================ University of Manchester E-mail: [email protected] ============================ http://manchester.academia.edu/DavidBriggs (v.sensible) http://xtaldave.wordpress.com/ (sensible) http://xtaldave.posterous.com/ (less sensible) Twitter: @xtaldave Skype: DocDCB ============================ On 7 December 2010 14:14, xiuwen zhang <[email protected]> wrote: > Dear Colleagues, > > Currently we got several very tiny crystals. After exposuring a cluster > of crystals one hour in home source, we could find some weak diffraction > spots. As the spots are too few for indexing, I am not quite sure whether > these tiny crystals are salt crystals or protein crystals. I appreciate your > experience on similar case. > > Attached files are two diffraction images at 0 and 90 degree. Thank you > very much for your kind help. > > Cheers, > Xiuwen
