Depending on the Space (Laue) group, there may be alternative indexing possibilities which will be sorted out in Pointless - did you run that program?
I would recommend using the ccp4i task "Symmetry, Scale, Merge (Aimless)" which uses Aimless instead of Scala - Aimless may be a bit more robust than Scala in some cases Other things to try. If you have several crystals, one (or more) may just be "bad". You can try scaling them separately, or using the "scale constant" option just to diagnose which crystals would be better omitted Phil On 10 May 2013, at 16:04, amit sharma <amit_sps2...@yahoo.co.uk> wrote: > Dear All, > > I have been trying to scale (using SCALA) the diffraction data set collected > from multiple crystals. Data was indexed using mosflm but fails to scale with > an error saying > "negative scale factors" when scaling was tried in a constant mode whereas it > fails to scale with an error saying "No observations" when scaling was tried > in a batch mode. Damping shifts were tried from 0.1 to 0.5 and also unit > weighting, but the scaling still fails with same errors. Can someone provide > any suggessions to deal with the problem. > > Kind Regards, > > Amit
