Dear Theresa, concerning your first sentence which is a bit short to my taste: if you index, you expect to find the cell parameters. These enable you to process the dataset. At the end of processing, a decision has to be made about the spacegroup. Only then structure solution can be tried, using the integrated intensities which are merged in the correct spacegroup. If the structure cannot be solved, one reason may be that the spacegroup decision has to be revised. All of these steps are well supported by software, but in specific cases they may nevertheless be difficult. Concerning your second sentence: INCLUDE_RESOLUTION_RANGE is how the user tells XDS about which reflections to include into scaling. It is _not_ something that XDS tells the user!
Concerning your questions: 1) inspect the final table in CORRECT.LP which starts with "SUBSET OF INTENSITY DATA WITH SIGNAL/NOISE >= -3.0 AS FUNCTION OF RESOLUTION". Look at the CC1/2 column. Those resolution shells which have a "*" after the numeric value still have statistically significant signal, and it makes sense to scale them. 2) FRAME.cbf is produced by COLSPOT and visualizes spot positions that are used for indexing. It is later overwritten by INTEGRATE and visualizes the last frame of the DATA_RANGE, with expected reflection areas superimposed. You should check the agreement of observed and expected (predicted) spots. Hope this helps, Kay On Mon, 8 Oct 2012 23:36:46 +0100, Theresa Hsu <theresah...@live.com> wrote: >Dear all > >I took some images from test crystal and tried to index them to get cell >parameters, not enough for structure solution. I can see spots at 3.5 A with >ADXV but when I indexed, XDS reports up to 3.0 A in INCLUDE_RESOLUTION_RANGE >in XDS_ASCII.HKL. > >Questions: > >1. How do I know that the spot at 3.0 is not background noise? >2. What is the function of FRAME.cbf file? > >Thank you. > >Theresa
