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Hi Sonya, the Relion import procedure is designed to work with STAR files for 3-D refinement. Not sure if there is a difference. However, it is not clear that it is necessary to recover any of the metadata from the .STAR file if your purpose is just to make the 2-D dynamics movies. EMAN will read .MRCS files natively. I would suggest trying the following: 1) in e2projectmanager go to particles -> import tools -> import particle stacks and import the per-micrograph .mrcs particle files (press Launch after selecting the particle file(s)) If you have merged all of the particles into a single .mrcs file then it will be impossible to perform CTF correction in EMAN2 unless you have a .star file EMAN2 can read to identify which particles came from which micrograph. However, for your present purpose, it may not be strictly necessary to perform CTF correction. Motion movies are not normally extraordinarily high resolution. 2) go to CTF -> CTF Autoprocess * Enter the correct microscope/image parameters * If the data is negative stain, set % AC to 70, if the data is cryo data, set it to 10 or 15 * If the data was collected using a phase plate, check that box * It is generally a very good idea to follow EMAN2's box size guidelines (http://eman2.org/BoxSize), but if you're in a hurry and find that the box is tighter than EMAN2 would prefer, check the 'extrapad' checkbox. This is not as good as re-extracting the boxed particles at a larger size, but will help at least. * if your particles appear dark on a lighter background, they must be contrast inverted for EMAN2 processing to work well. In this case check the 'invert' checkbox. * set 'threads' to the number of cores on the computer you are using (not GPU) Press Launch once everything is set 3) When step 2 is complete (you can monitor progress by pressing the 4th icon from the top on the right edge of the project manager), you may wish to use Visual CTF to insure that the CTF fitting went well. Insure that "allparticles" and "sortdefocus" are checked. If the defocus seems correct for the first few and the last few micrographs in the list, then things are probably fine. If you encounter any incorrect defocuses (a rare occurrence) you can manually adjust the defocus to something near the correct value and hit the "refit" button. If you do any manual adjustments, you should rerun step 2 when you are done. 4) You might also want to consider running the 2D Analysis -> Bispectrum-based Class Averaging step, and compare results with your Relion class averages. * input should be sets/all__ctf_flip_fullres.lst * ncls is the number of classes to generate * iter should be 1 or 2 * nbasisfp should be 10 typically * parallel should be thread:<number of cores> you shouldn't need to change any of the advanced options. After running (it should not take long), results are in r2db_* 5) you can launch an image browser/viewer with the top button on the right hand edge of the project manager to look at your various image files Step 4 is not strictly necessary before following the instructions I sent, though class-averages from EMAN2 may serve as better alignment references for those instructions. If you had been able to successfully import a STAR file, that process would have performed steps 1-3 above for you. cheers -------------------------------------------------------------------------------------- Steven Ludtke, Ph.D. Charles C. Bell Jr., Professor of Structural Biology Dept. of Biochemistry and Molecular Biology (www.bcm.edu/biochem<http://www.bcm.edu/biochem>) Co-Director CIBR Center (www.bcm.edu/research/cibr<http://www.bcm.edu/research/cibr>) Co-Director National Center For Macromolecular Imaging (ncmi.bcm.edu<http://ncmi.bcm.edu>) Baylor College of Medicine [log in to unmask]<mailto:[log in to unmask]> On Jan 25, 2018, at 6:18 AM, Sonya James <[log in to unmask]<mailto:[log in to unmask]>> wrote: Hello, I have done some 2D Class averages in Relion - I want to transfer the results to EMAN2 so that I can make flexibility movies. But when I try to import_particles using the particles.star file from the Relion Select job (ie all the particles from the class averages that I have selected as good) I get error messages. I wonder am I not selecting the correct .star file?? Any suggestions Thanks Sonya