Known issue: Difference between revisions
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=== Reconstruction sometimes gives strong stripy artifacts === | === Reconstruction sometimes gives strong stripy artifacts === | ||
This is a nasty bug in the reconstruction algorithm, which mostly seems to affect reconstructions from many particles, and only the 3D auto-refine option. The effects on the reconstruction can be disastrous: your molecule may disappear completely and you may end up with a stripy pattern instead. Note that if this happens in only one of the two half-reconstructions, it may go by unnoticed (if you don't inspect both half-reconstruction at each iteration) and may just appear as a sudden drop in resolution. | This is a nasty bug in the reconstruction algorithm, which mostly seems to affect reconstructions from many particles, and only the 3D auto-refine option. The effects on the reconstruction can be disastrous: your molecule may disappear completely and you may end up with a stripy pattern instead. Note that if this happens in only one of the two half-reconstructions, it may go by unnoticed (if you don't inspect both half-reconstruction at each iteration) and may just appear as a sudden drop in resolution. Somehow, this bug is system-dependent and sometimes hard to reproduce. | ||
However, the bug can be circumvented by changing line 658 in <code>src/backprojector.cpp</code> from: | |||
double myfsc = XMIPP_MAX(0., DIRECT_A1D_ELEM(fsc, i)); | double myfsc = XMIPP_MAX(0., DIRECT_A1D_ELEM(fsc, i)); | ||
to: | to: | ||
double myfsc = XMIPP_MAX(0.001, DIRECT_A1D_ELEM(fsc, i)); | double myfsc = XMIPP_MAX(0.001, DIRECT_A1D_ELEM(fsc, i)); | ||
Revision as of 10:52, 9 November 2012
Release 1.1
Reconstruction sometimes gives strong stripy artifacts
This is a nasty bug in the reconstruction algorithm, which mostly seems to affect reconstructions from many particles, and only the 3D auto-refine option. The effects on the reconstruction can be disastrous: your molecule may disappear completely and you may end up with a stripy pattern instead. Note that if this happens in only one of the two half-reconstructions, it may go by unnoticed (if you don't inspect both half-reconstruction at each iteration) and may just appear as a sudden drop in resolution. Somehow, this bug is system-dependent and sometimes hard to reproduce.
However, the bug can be circumvented by changing line 658 in src/backprojector.cpp
from:
double myfsc = XMIPP_MAX(0., DIRECT_A1D_ELEM(fsc, i));
to: double myfsc = XMIPP_MAX(0.001, DIRECT_A1D_ELEM(fsc, i));
Then recompile relion using make -j 4 && make install
This will be fixed in the next release.