Search NASA⌕ Search

Engineering topics

Johnson, Owen

Publications and source records attributed to Johnson, Owen.

Autoindexing diffraction images with iMosflm

The principles of one-dimensional FFT-based autoindexing of diffraction images are described together with practical issues that may arise. A procedure for indexing multiple lattices as implemented in iMosflm is presented. An overview of autoindexing diffraction images based on one-@@dimensional fast Fourier transforms is presented. The implementation of the algorithm in the Mosflm/iMosflm program suite is described with a discussion of practical issues that may arise and ways of assessing the success or failure of the procedure. Recent developments allow indexing of images that show multiple lattices, and several examples demonstrate the success of this approach in real cases.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

iMOSFLM: a new graphical interface for diffraction-image processing with MOSFLM

A new graphical user interface to the MOSFLM program has been developed to simplify the processing of macromolecular diffraction data. The interface, iMOSFLM, allows data processing via a series of clearly defined tasks and provides visual feedback on the progress of each stage. iMOSFLM is a graphical user interface to the diffraction data-integration program MOSFLM. It is designed to simplify data processing by dividing the process into a series of steps, which are normally carried out sequentially. Each step has its own display pane, allowing control over parameters that influence that step and providing graphical feedback to the user. Suitable values for integration parameters are set automatically, but additional menus provide a detailed level of control for experienced users. The image display and the interfaces to the different tasks (indexing, strategy calculation, cell refinement, integration and history) are described. The most important parameters for each step and the best way of assessing success or failure are discussed.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗