Hi all, I'm working on a cryo-EM reconstruction where I have some flexible low-resolution elements (RNA double helices). They have different orientations relative to my reference model, but I would like to model them in the approximately correct position. I've tried real_space_refine with morphing and simulated annealing, but neither accomplish what I want. Now I'm thinking of cutting out these helices and manually position them approximately where I want them. But I fear that this will case headache at the "joint". Is it possible to use the manual positions as a reference for positional restraints, but use the original model as the reference for the torsion angles. Is this possible with real_space_refine? Or is there a better way of refining this structure? Regards, Daniel När du har kontakt med oss på Uppsala universitet med e-post så innebär det att vi behandlar dina personuppgifter. För att läsa mer om hur vi gör det kan du läsa här: http://www.uu.se/om-uu/dataskydd-personuppgifter/ E-mailing Uppsala University means that we will process your personal data. For more information on how this is performed, please read here: http://www.uu.se/en/about-uu/data-protection-policy