Dear Colleague, As a developer or trusted user of SasView we would like to elicit your help in road-testing the first release candidate (rc1) of the new version of the program ahead of its full release! You can find MacOS and Windows installers for 5.0.5rc1 here: https://github.com/SasView/sasview/releases/tag/v5.0.5rc1 With this release we are also pleased to welcome six new contributors to the SasView collaboration! Though version 5.0.5 does feature the usual mix of bug fixes, functionality improvements, documentation enhancements, and naturally some new features (more on those in a moment), this version is significant for another reason: it is the first time we will release from GitHub Actions instead of our Travis/Jenkins build system. This change helps future-proof our ability to continue to develop SasView with our limited resources but does come with a one-time penalty. To build SasView with GitHub Actions many of the library packages we use, including the Python version, have had to be upgraded/downgraded. The only way to find out if this has had any undesirable consequences is by putting the program through its paces, and this is where we hope you can assist us! New Features - The ability of the Generic Scattering Calculator Tool to handle magnetic/polarised neutron computations has been completely overhauled and enhanced. As part of this, coordinate data in some VTK formats are now also supported. - The program will now read multiple SASdata blocks in a single SASentry in CanSAS1D XML data files. - In-program data can now also be saved to CSV data files. Functionality Improvements - The data loaders should now be more resilient. - The Q-range 'sliders' are now fully restored, and can be toggled off/on. - The Custom Model Editor now supports some syntax checking and error reporting. - Uncertainty handling on constrained parameters is now propagated correctly. Testing of this release candidate will run from now until mid-January 2022. Please report bugs and comments to help@sasview.org<mailto:help@sasview.org>, remembering to specify which platform (Mac/Win) you are using and attaching a copy of your sasview.log file where possible. For any complicated/hard-to-describe bugs, providing the steps to reproduce the issue is extremely helpful. We hope you like SasView 5.0.5, and thank you for your help! The SasView Development Team https://www.sasview.org/ This email and any attachments are intended solely for the use of the named recipients. If you are not the intended recipient you must not use, disclose, copy or distribute this email or any of its attachments and should notify the sender immediately and delete this email from your system. UK Research and Innovation (UKRI) has taken every reasonable precaution to minimise risk of this email or any attachments containing viruses or malware but the recipient should carry out its own virus and malware checks before opening the attachments. UKRI does not accept any liability for any losses or damages which the recipient may sustain due to presence of any viruses.