4.0.1

This is the first maintenance release of RELION 4.0. We recommend all RELION users to upgrade to this version, because this fixes bugs, improves compatibility and introduces convenient features.

New features and bug fixes include:

• Supported MRC movies compressed by bzip2, xz or ZStandard in RELION's motion correction and Bayesian Polish for SPA. You need pbzip2, xz or zstd command in your PATH, respectively. Please read our documentation for the details.
• Supported CUDA 12 (39c3538)
• Repaired C10 to C19 point groups (0c110f6, thanks to @huwjenkins)
• Fixed the CTF-premultiplication flag upon re-extraction (db5f635)
• Repaired implicit 3.0 to 3.1 STAR format conversion (042319e)
• Supported the latest CTFFIND (f6edba3)
• Fixed a memory issue (9908f51, thanks to @do-jason)

4.0.0

This is the first stable version of RELION 4.0. With the release of this version, earlier RELION versions (3.1.x) are no longer supported. We recommend all RELION users to upgrade to this version.

For the list of new features, please look at the "What's new?" page in our documentation and the following papers.

• "New tools for automated cryo-EM single-particle analysis in RELION-4.0" Biochem. J., 2021
• "A Bayesian approach to single-particle electron cryo-tomography in RELION-4.0" bioRxiv, 2022

3.1.4

This is the final maintenance (bug fix) release from RELION 3.1.3. RELION 4.0 succeeds this release. We will no longer investigate and fix bugs in RELION 3.1.x.

The most important change since RELION 3.1.3 is that symmetry relaxation for non-cyclic point groups was blocked. This feature has been broken for non-cyclic point groups but earlier versions allowed the job to run, giving wrong results (see issue #796). The --helical_nstart option of relion_refine was also repaired (see #799).

In addition to these, various bugs (resource leaks, buffer overflows etc) were fixed and compatibility with newer compilers/environments was improved. See Git commit logs for the details.

3.1.3

This is a maintenance (bug fix) release from RELION 3.1.2. Everyone using RELION 3.1.2 or earlier should upgrade to this version. We will not investigate bug reports and questions on earlier versions.

Changes since RELION 3.1.2 include:

• Compatibility fix with CUDA 11.5 (by Alexey Romanenko)
• Compatibility fix with Intel oneAPI SDK (by Intel engineers)
  Please see installation manual to learn how to use Intel compilers. Do not use CC, CXX, MPICC, MPICXX environmental variables.
• Fix race conditions in local scratch (by Andreas Schenk)
• Fixed buffer overflow in FileName::compose (by Andreas Schenk)
• relion_convert_to_tiff: treat MODE 0 MRC as signed
• MotionCorr: treat pixels with zero gain as defects even in non-EER movies
• Bayesian Polish: fix defects in EER
• Gentle clean: remove duplicated code
• EER: prevent crash in corrupted EER files

3.1.2

This is a minor update from RELION 3.1.1. Everyone using RELION 3.1.1 or earlier should upgrade to this version. We will not investigate bug reports and questions on earlier versions.

Changes since RELION 3.1.1 include:

• We are migrating documentation from RELION wiki to ReadTheDocs.
• libtiff is no longer optional; it is necessary for compilation
• Switch to FFTW 3.3.8 from 3.3.4 (earlier versions are broken for GCC 8: http://www.fftw.org/release-notes.html)
• Support the AMD-optimized version of FFTW with the -DAMDFFTW ONoption in CMake
• 3DCTF: fix a bug reported by @dtegunov (#710)
• relion_image_handler: do not add image index to filenames in STAR file if an image file is not a stack (#705)
• CTFFIND wrapper: support (non-movie) TIFF images (#728, thanks to @gruchalla)
• GUI: do not add --sigma_rot, --sigma_tilt, --sigma_psi for local search in Refine3D
• Suppress warnings about private TIFF tags in EER (#735)
• Multibody: support SIDESPLITTER (please use the latest wrapper)
• Fix issues with undefined labels in STAR files (#641)
• Replace controversial technical terms regarding MPI (#739)

Unfortunately, there are several remaining issues to be fixed in later updates. Frequent problems include:

• Reboxing in a subtract job consumes a huge amount of RAM. This is actually a GLIBC, not RELION, issue. A workaround is described in #673.
• It might fail to compile with GCC and Intel MKL on some Linux distributions. A patch (58bffcb) is described in #731.

See https://github.com/3dem/relion/issues for details.

3.1.1

This is a minor update from RELION 3.1.0. Everyone using RELION 3.1.0 or earlier should upgrade to this version.

Changes since RELION 3.1.0 include:

• Supported the EER movie format for Falcon4.
  Please read https://www3.mrc-lmb.cam.ac.uk/relion/index.php/Image_compression#Falcon4_EER carefully for detailed instructions.
• Changed defect correction to use a random pick from neighboring good pixels, instead of the average of them.
• Fixed --keep_ctfs_micrographs in Extract to respect the optics groups in the micrograph STAR file.
• Updated Gentle Clean to delete temporary files from CtfRefine.
• Merged optimizations for GPU (--gpu) and Intel CPUs (--cpu) contributed by NVIDIA and Intel engineers.

Unfortunately, there are several remaining issues to be fixed in later updates. Frequent problems are:

• SIDESPLITTER does not work with Multibody refinement.
• Use of undefined labels in STAR files causes problems with some components (e.g. Extract). #641
• Memory leak in Subtract job (could not be reproduced at LMB). #673

See https://github.com/3dem/relion/issues for details.

3.1.0

This is the first stable release of RELION 3.1.0.
Everyone using RELION 3.0.x or 3.1 beta should upgrade to this version.

Major changes since RELION 3.0.x include:

• High-order aberration correction & anisotropic magnification correction in CTF refinement
  (https://doi.org/10.1107/S2052252520000081)
• External jobtype to run third-party software in the RELION pipeline
• Schedules for designing & executing on-the-fly processing procedures
• Tweaks to GUI, pipeliner and helical processing
• Symmetry relaxation (special thanks to Vahid Abrishami for code contribution)

The new tutorial is available at ftp://ftp.mrc-lmb.cam.ac.uk/pub/scheres/relion31_tutorial.pdf.

Support for the EER movie format is not yet included in this release.
Please use a special version in the devel-eer branch at https://github.com/3dem/relion/tree/devel-eer.
This feature will be merged in near future as a minor update (version 3.1.x).

Release 3.0.8

This release contains several bug fixes. As we start public beta testing of RELION 3.1, we will not fix non-critical bugs for version 3.0.x in future.

• Refine3D: don't allow Refine3D on even number of MPI processes.
• relion_mask_create: fixed --and, --or, --and_not, --or_not. (GitHub issue #495)
• Extract: repair uninitialised variables that resulted in wrong OriginX/Y values of the first particles in each micrograph
• GUI: use --reconstruct_subtracted_bodies in continuation as well (as reported by Dr. Yanagisawa)

Release 3.0.7

This release fixes an MPI-related bug where refinement and classification stall at the beginning or at a certain iteration. (GitHub issue #473 and problems reported in CCPEM by Wim Hagen, Dieter Blaas and others)

Release 3.0.6

This release has several improvements:

• RelionCor supports dose weighting of datasets at 100 kV.

• The inter-particle distance cutoff in the Laplacian-of-Gaussian (LoG) picker was improved.
  When LoG picker is enabled, minimum inter-particle distance in the "autopicking" tab is not used. This is by design. Instead, neighbouring particles within
  (detected diameter at the point + --LoG_diam_min) * --LoG_neighbour / 100
  are avoided. The default for --LoG_neighbour is 100 %. You can make this smaller or larger to pick more or less, respectively.

• Implemented --LoG_upper_threshold option.
  LoG picker tended to pick high contrast contamination like ice and ethane droplets. They have higher scores than real particles, so adjust default threshold is useless. Now we have --LoG_upper_threshold option to set an upper limit in scores. Useful values are typically 1.5 to 4. The default is 99999 (i.e. no limit in practice)

This release also contains the following bug fixes.

• PostProcess: fixed a bug where postprocess_masked.mrc is overwritten by half2_masked.mrc when --half_maps is provided (reported by @keitaroyam).
• Stability of histogram generation was improved.
• Prevented "too long arguments" errors in scratch (issue #467 reported by @EMBL-Structures).
• relion_star_handler --split: removed an assumption on the number of digits.
• AutoPicker: rejects 3D references for filaments (CCPEM https://www.jiscmail.ac.uk/cgi-bin/webadmin?A2=ind1906&L=CCPEM&O=D&P=6094).