Hi Everyone, Just wanted to let everyone know that i was able to process this dataset with XDS ( and lots help from experts !)
Thanks again Mahesh On Mon, Aug 19, 2013 at 5:07 PM, Petri Kursula <petri.kurs...@oulu.fi>wrote: > I have often processed images like this with XDS. Of course, you will get > a better quality of data with a more optimal strategy, but I would never > say never. If I had a penny every time people told me 'you cannot process > that'… > > Petri > > On Aug 19, 2013, at 11:40 PM, Mahesh Lingaraju <mxl1...@psu.edu> > wrote: > > > Thank you experts for your valuable suggestions. I think Ill try to solve > it by proper data collection strategy the next time as i am unable to > process my current data even with the tricks that were mentioned here. > > Thanks again > > Mahesh > > On Fri, Aug 16, 2013 at 2:04 PM, Bosch, Juergen <jubo...@jhsph.edu> wrote: > >> tilted is what I meant at an angle of e.g. 30 or 60 degrees. Works fine >> with most SSRL beamlines except of the 12-2 microfocus - but that might >> have been fixed in the meantime. >> >> Jürgen >> >> On Aug 16, 2013, at 1:57 PM, Bosch, Juergen wrote: >> >> for #2) >> >> I'd suggest get some of those Mitigen loops that are titled. I assume >> you have hexagonal plates as crystals and you really want to shoot along >> the thin area of the crystal down the sixfold. With normal loops it's an >> art to get that crystal to sit upright in the loop but not impossible if >> you take smaller loops. >> >> My longest axis collected was 420 Å to ~2 Å resolution by this method. >> >> Jürgen >> >> On Aug 16, 2013, at 1:46 PM, Zbyszek Otwinowski wrote: >> >> This is clearly a case of a crystal with a very long unit cell; a case >> which should be approached mindfully. >> >> HKL2000 has a default search for indexing solutions such that diffraction >> along the longest unit cell will be resolved, with the assumed spot size. >> >> The problem with such diffraction has 2 aspects: >> 1) how to process the already collected data where the spots are close to >> each other; >> 2) how to collect future data. >> >> Ad 1) The best solution is to reduce the spot size, so the spots are >> resolved. This may require an adjustment of spot size by a single pixel; >> one should not only change spot radius, but also change the box size >> between even and odd number of pixels in the box dimensions. >> >> Just changing the spot radius changes the spot diameter by an even number >> of pixels, so if one wants to change the spot diameter by one pixel, one >> has to change the box size. This is the consequence of the spot being in >> the center of the box. >> >> Just during indexing, there is also a workaround by specifying the command >> before indexing: longest vector followed by a number that defines the >> upper limit of the cell size. This may help finding indexing, but will >> create overlaps between spots during refinement and integration. >> >> This dataset presents a problem of collecting data by rotating on the axis >> perpendicular to the long unit cell. In consequence, the Image 1 has >> essentially (barely differing in centroid position) overlapping spots, so >> it would be hard to process them meaningfully by any program. >> >> Ad. 2) What would be a better way to collect data in the future? >> >> >> Hi CCP4 folks >> >> >> I have a data set which is looks twinned ( see the image-1 - I zoomed >> on >> >> to the image so that one can spot the twinning. Furthermore, the spots are >> >> very smeary from ~ 30 - 120 degrees of data collection, see image 2) I >> >> tried using HKL2000 and mosflm to process this data but i cannot process >> >> it. I was wondering if anyone has any ideas as to how to process this data >> >> or comments on whether this data is even useful. Also, I would really >> >> appreciate if someone could share their experiences on solving twinning >> >> issues during crystal growth >> >> >> Thanks in advance ! >> >> >> Mahesh[image: Inline image 2][image: Inline image 3] >> >> >> >> >> Zbyszek Otwinowski >> UT Southwestern Medical Center at Dallas >> 5323 Harry Hines Blvd. >> Dallas, TX 75390-8816 >> Tel. 214-645-6385 >> Fax. 214-645-6353 >> >> >> ...................... >> Jürgen Bosch >> Johns Hopkins University >> Bloomberg School of Public Health >> Department of Biochemistry & Molecular Biology >> Johns Hopkins Malaria Research Institute >> 615 North Wolfe Street, W8708 >> Baltimore, MD 21205 >> Office: +1-410-614-4742 >> Lab: +1-410-614-4894 >> Fax: +1-410-955-2926 >> http://lupo.jhsph.edu >> >> >> >> >> >> ...................... >> Jürgen Bosch >> Johns Hopkins University >> Bloomberg School of Public Health >> Department of Biochemistry & Molecular Biology >> Johns Hopkins Malaria Research Institute >> 615 North Wolfe Street, W8708 >> Baltimore, MD 21205 >> Office: +1-410-614-4742 >> Lab: +1-410-614-4894 >> Fax: +1-410-955-2926 >> http://lupo.jhsph.edu >> >> >> >> >> > >
