Hello Marco, There are schools that will teach you about the software (and theory) used in crystallography and they tend to be very good, so one suggestion is to enroll in one of these 1-2 week courses to learn everything properly.
You should process all of your data sets- it is only after having processed everything you will be able to look at the log files and determine what frames/ images you may want to discard. These log files should also give you an estimate as to whether you have enough selenium signal to solve the structure. For the CCP4 suite, Aimless is the program that will give you the merging statistics. Pointless is run just before Aimless and will give you its best guess as to the space group (and yes, sometimes the space group will be ambiguous at this point in the process). Pointless/Aimless also allow you to merge multiple data sets from the same crystal. As to whether you can merge data sets from different crystals- you will need to process each one independently first and then determine whether they are isomorphous to each other- if they are, you can merge them if you think it will be helpful. Hopefully that is a starting point for you. Best regards, tom ________________________________ From: CCP4 bulletin board <CCP4BB@JISCMAIL.AC.UK> on behalf of Marco Bravo <0000d0eb7bee83ae-dmarc-requ...@jiscmail.ac.uk> Sent: Thursday, May 23, 2024 11:01 AM To: CCP4BB@JISCMAIL.AC.UK <CCP4BB@JISCMAIL.AC.UK> Subject: [ccp4bb] Data Processing questions [You don't often get email from 0000d0eb7bee83ae-dmarc-requ...@jiscmail.ac.uk. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ] Hi All, I just collected a lot of data for native crystals and Seleno-methionine derivative crystals. I have a couple of questions 1. How do I know which images to process and which ones to exclude which might be radiation damaged and not be good to further process? I have been told it is possible to cutoff the damaged images, how do I know where to cut it off? 2. I also collected MAD data at two wavelengths (Remote, and at the arithmetic mean of the peak and inflection) and three for some crystals (remote, peak, and inflection), How do I proceed about solving the structure with this data and how should I process them? Is there an advantage to 3 wavelengths over 2 for MAD? 3. For some crystals I collected multiple datasets from the same crystal. I have been told I can merge the datasets (images) into a single, larger dataset. How do I do that? Can I combine datasets from different crystals grown under the same conditions with the same material? Or only the same individual crystal? Is it advantageous to merge datasets like this? 4. When Elves indexes the crystal initially, it always thinks the space group is P4. When I finish data collection it thinks P21 21 2. Is this normal? Is elves just guessing wrong initially? Why would my space group be ambiguous? Our resolution is around 3 angstroms. Thank You! ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 This message was issued to members of www.jiscmail.ac.uk/CCP4BB<http://www.jiscmail.ac.uk/CCP4BB>, a mailing list hosted by www.jiscmail.ac.uk<http://www.jiscmail.ac.uk>, terms & conditions are available at https://www.jiscmail.ac.uk/policyandsecurity/ ######################################################################## To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 This message was issued to members of www.jiscmail.ac.uk/CCP4BB, a mailing list hosted by www.jiscmail.ac.uk, terms & conditions are available at https://www.jiscmail.ac.uk/policyandsecurity/
