Hampton Research actually sells bent loops. At least used to. Raji
On Tue, Apr 5, 2011 at 8:52 AM, Jacob Keller <j-kell...@fsm.northwestern.edu > wrote: > For plate crystals with the long axis normal to the plate surface > (anecdotally, this is usually the case), you can use bent loops. Bent > loops can be made using tweezers by folding over the loop onto the > stem and crimping with the tweezers. When the loop relaxes a bit, it > will leave a ~90deg-bent loop, so the crystal can sit on the loop and > be shot edge-on in the beam. It takes a bit of time to get it right, > but it worked well for me one time. > > JPK > > On Tue, Apr 5, 2011 at 7:29 AM, Jürgen Bosch <jubo...@jhsph.edu> wrote: > > What do you consider long ? 200, 300 ? 600 A ? Before shooting try to run > > strategy or xplan. Move the detector back to first reliably be able to > > determine your cell. Then double your estimated mosaicity and see what > > strategy suggests. If you don't get many overlaps (<5%) then try a closer > > distance. Don't rotate 1degrees but take 1/2 of the mosaicity. Obviously > you > > want to make good use of the detector area so adjust the edges to where > your > > crystal really diffracts. And if that resolution leads to too many > overlaps > > then limit your resolution and get first a good datasets home. You then > can > > play with 2theta for a higher resolution dataset. > > Another obvious thing to do and you don't mention what reduction program > you > > use is to let XDS sort your problem out. Unless you collected to high > > resolution without being cautious XDS could help. If not, well then you > had > > your experience and now should know better. > > SSRL has options to collect 450 A cells to 3A without much hassle. That > was > > my largest cell so far. > > Jürgen > > > > ...................... > > Jürgen Bosch > > Johns Hopkins Bloomberg School of Public Health > > Department of Biochemistry & Molecular Biology > > Johns Hopkins Malaria Research Institute > > 615 North Wolfe Street, W8708 > > Baltimore, MD 21205 > > Phone: +1-410-614-4742 > > Lab: +1-410-614-4894 > > Fax: +1-410-955-3655 > > http://web.mac.com/bosch_lab/ > > On Apr 5, 2011, at 1:05, dengzq1987 <dengzq1...@gmail.com> wrote: > > > > hello all, > > does anyone have the experience of > Collecting Data from Long Unit Cell Axes > > ? I have a crystal that diffracts to about 4 A. in some direction the > spots > > overlap. we can't use the data to index .we think it is because that > there > > is a long unit cell axes. so is there any method to solve this problem? > > > > best wishes. > > > > 2011-04-05 > > ________________________________ > > dengzq1987 > > > > -- > ******************************************* > Jacob Pearson Keller > Northwestern University > Medical Scientist Training Program > cel: 773.608.9185 > email: j-kell...@northwestern.edu > ******************************************* > -- ----------- Raji Edayathumangalam Research Fellow in Neurology, Harvard Medical School Postdoctoral Fellow, Center for Neurologic Diseases, Brigham and Women's Hospital Visiting Research Scholar, Brandeis University
