Software Tools For Molecular Microscopy/Specific packages

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Packages that offer a comprehensive set of tools to permit the analysis of data in a single class of structural problem. For example packages specifically focused on objects with helical, icosahedral, crystalline symmetry, etc.

Two-dimensional crystals[edit]

2dx

  • Website: http://2dx.org/
  • Current version: 3.1.0
  • Contact: Henning.Stahlberg@unibas.ch
A software system designed as a user friendly, platform-independent software package for electron crystallography. 2dx assists in the management of an image-processing project, guides the user through the processing of 2D crystal images, and provides transparence for processing tasks and results. Algorithms are implemented in the form of script templates reminiscent of c-shell scripts. It includes a single-particle Maximum Likelihood module, and 3D merging capability. 2dx builds upon the MRC programs, which were extended by additional functions to interface with the GUI of 2dx, and to implement the optionally automatic processing.
  • Support: Operating systems: Mac OS X, Linux Image format support: MRC, TIFF, CCP4
  • Cost: Free/Open Source, GPL
  • Primary Publication to Cite:
  • Additional References:

Icosahedral viruses[edit]

AUTO3DEM

An automation system designed to accelerate the computationally intensive process of three-dimensional structure determination from images of vitrified icosahedral virus particles. With minimal user input and intervention, AUTO3DEM manages the flow of data between the major image reconstruction programs, monitors the progress of the computations, and intelligently updates the input parameters as the resolution of the model is improved.

Helices[edit]

BBHP - Burnham-Brandeis Helical Package

The Brandeis Helical Package has been in use in one form or another for quite some time. Originally developed for VAX/VMS it has been modified, expanded, and ported several times. We first ported the package to Linux in 2006, using the Portland Group compilers. Subsequently we rewrote portions of the fortran code which were not supported by GNU fortran (g77) and now the package compiles and runs with gcc/g77. This has allowed us to support extra modern platforms. The re-christened Burnham-Brandeis Helical Package will now run on 32-bit Linux, 64-bit Linux, Mac OS X (Intel) and even Windows running Cygwin. At the same time, when porting to Linux, we took the opportunity to replace the main GUI portions of the package with updated programs. We had spent some time modifying the Tcl/Tk-based GUI programs Tkir (image viewer) and Tkll (layerline viewer) from SUPRIM to support a plugin architecture, where we could write new plugins to add functionality without further modifications to the core code-base. The first, tkinterp, provides an interface in Tkir for selecting layerlines, replacing the old interp program. The second, brandeisll, is a Tkll plugin to provide support for displaying the Burnham-Brandeis Helical Package "interp" layerline and bessel-function format. We've also included as part of the package, the AVID software for analyzing the variance within the helix.
  • Support: Operating systems: Linux Image format support: MRC
  • Cost: Free
  • Primary Publication to Cite:
    • Owen CH, Morgan DG, DeRosier DJ (1996). "Image analysis of helical objects: the Brandeis Helical Package". J. Struct. Biol. 116: 167–175. PMID 8742740. 
  • Additional References:
    • Rost LE, Hanein D, DeRosier DJ (1998). "Reconstruction of symmetry deviations: a procedure to analyze partially decorated F-actin and other incomplete structures". Ultramicroscopy 72: 187–197. PMID 9639941. 

IHRSR

  • Website:
  • Contact: egelman@virginia.edu
The iterative helical real space reconstruction (IHRSR) algorithm can recontruct helical filaments under conditions when traditional Fourier–Bessel approaches sometimes fail. For example when there is disorder or heterogeneity present, when the specimens diffract weakly, or when Bessel functions overlap.
  • Support: Operating systems: Linux Image format support: SPIDER
  • Cost: Free
  • Primary Publication to Cite:
    • Egelman EH (January 2007). "The iterative helical real space reconstruction method: surmounting the problems posed by real polymers". J. Struct. Biol. 157 (1): 83–94. doi:10.1016/j.jsb.2006.05.015. PMID 16919474. 

Phoelix

A set of procedures and algorithms for helical processing that we refer to as the PHOELIX package. The package was developed to provide a time-efficient and semiautomated method for determining a three-dimensional density map from a specimen with helical symmetry. The procedures which are part of PHOELIXn are drawn from the original MRC helical processing suite with extensions principally developed using the SUPRIM image processing package. The package in its current form has been optimized for the processing of actomyosin filaments but has been modified and applied to other helical structures.
  • Support: Operating systems: Unix Image format support: MRC/suprim
  • Cost: Free/Open Source
  • Primary Publication to Cite:
    • Whittaker M, Carragher BO, Milligan RA (June 1995). "PHOELIX: a package for semi-automated helical reconstruction". Ultramicroscopy 58 (3-4): 245–59. PMID 7571117. 
  • Additional References:

Ruby-Helix

Set of programs for the analysis of “helical” objects with or without a seam. Ruby-Helix is built on top of the Ruby programming language and is the first implementation of asymmetric helical reconstruction for practical image analysis. It also allows easier and semi-automated analysis, performing iterative unbending and accurate determination of the repeat length.
  • Support: Operating systems: Fedora, Mac OS X Image format support: MRC
  • Cost: Free/Open Source, GPL
  • Primary Publication to Cite:
    • Metlagel Z, Kikkawa YS, Kikkawa M (January 2007). "Ruby-Helix: an implementation of helical image processing based on object-oriented scripting language". J. Struct. Biol. 157 (1): 95–105. doi:10.1016/j.jsb.2006.07.015. PMID 16996276. 
  • Additional References:

Stokes Lab Procedures

Image Processing Software for Helical Crystals: outlines, procedures and hints for using the MRC helical processing software which has since been modified by several groups including Chikashi Toyoshima, Nigel Unwin, David DeRosier and David Stokes.
  • Support: Operating systems: Unix Image format support: MRC
  • Cost: Free/Open Source
  • Primary Publication to Cite:
    • Unpublished

Single particles[edit]

Frealign

Frealign provides algorithms optimized for the efficient refinement of three-dimensional reconstructions and correction for the contrast transfer function of the microscope in the determination of macromolecular structures by single particle electron microscopy.
  • Support: Operating systems: Linux, IRIX, OSF, Mac OS X Image format support: MRC, Spider, IMAGIC
  • Cost: Free/Open Source, GPL
  • Primary Publication to Cite:

PFT3DR

PFT3DR is package for determining orientations and origins of imaged particles and computing a three-dimensional reconstruction from the images and their assigned orientations and origins. The programs are enhanced versions of the PFT algorithm developed by Baker and Cheng (2000) and the Fourier Bessel reconstruction algorithm of Crowther et al. (1970). The original adaptations of the PFT3DR programs were specific to icosahedral viruses, but were enhanced to support nearly all symmetries found in biological particles. Other enhancements are described on the PFT3DR web site.

RELION

RELION (for REgularised LIkelihood OptimisatioN, pronounce rely-on) is a stand-alone computer program that employs an empirical Bayesian approach to refinement of (multiple) 3D reconstructions or 2D class averages in electron cryo-microscopy (cryo-EM). It is developed in the group of Sjors Scheres at the MRC Laboratory of Molecular Biology. Briefly, the ill-posed problem of 3D-reconstruction is regularised by incorporating prior knowledge: the fact that macromolecular structures are smooth, i.e. they have limited power in the Fourier domain. In the corresponding Bayesian framework, many parameters of a statistical model are learned from the data, which leads to objective and high-quality results without the need for user expertise.
  • Support: Operating systems: Unix (Linux, Mac OS X, etc.) Image format support: MRC, Spider
  • Cost: Free/Open Source
  • Primary Publication to Cite:

Search/Refine/Build

Search_Fspace, Refine_Fspace, and Build_Fspace, are relatively simple programs for calculating and refining 3D maps. Many of the approaches used are similar to approaches applied by Frealign. The website provided also has a number of other useful utilities for working on micrographs, stacks of MRC images, and parameter files.
  • Support: Operating systems: Linux Image format support: MRC
  • Cost: Free/Open Source, GPL
  • Primary Publication to Cite:
    • Lau, W.C.Y, Rubinstein, J.L. (2012). "Subnanometre-resolution structure of the intact Thermus thermophilus H+-driven ATP synthase". Nature 481: 214-218. PMID 22753497. 
  • Additional References:
    • Benlekbir S, Bueler SA, Rubinstein JL (2012). "Structure of the vacuolar-type ATPase from Saccharomyces cerevisiae at 11-Å resolution". Nature Structural and Molecular Biology 19 pages=1356-52. PMID 23142977. 

Tomography[edit]

EM3D

EM3D is a software application designed to analyze and visualize electron microscope (EM) tomography data. It is especially for cellular and molecular biologists. From a tilt series of 2D electron micrographs taken at many tilt angles with respect to the electron beam, this program can then perform auto-align and quickly render those data into a lucid 3D model, which allows you to perform object rotating for viewing. In addition, EM3D also provides analysis tools for quantify structural information from the models, including their moments, proximity relationships, and spatial reliability. And all of these functions can be executed with a very intuited graphic user interface. EM3D is available free-of-charge Mac OS X for PowerPC or Intel, and Windows. EM3D was developed in the laboratory of Dr. U. J. McMahan, Professor of Neurobiology and of Structural Biology at Stanford University School of Medicine and continues to be developed at the Dept. of Biology, Texas A&M University.
  • Support: Operating systems: Windows, Mac OS X for PowerPC or Intel Image format support:
  • Cost: Free for academic use
  • Primary Publication to Cite:
    • Ress D, Harlow ML, Schwarz M, Marshall RM, McMahan UJ (1999). "Automatic acquisition of fiducial markers and alignment of images in tilt series for electron tomography". J Electron Microsc (Tokyo) 48 (3): 277–87. PMID 10425746EM3D's scheme for the automatic alignment of tilt-images is described. 
  • Additional References:
    • Ress DB, Harlow ML, Marshall RM, McMahan UJ (October 2004). "Methods for generating high-resolution structural models from electron microscope tomography data". Structure 12 (10): 1763–74. doi:10.1016/j.str.2004.07.022. PMID 15458626EM3D approach to model generation is detailed. 
    • Harlow ML, Ress D, Stoschek A, Marshall RM, McMahan UJ (January 2001). "The architecture of active zone material at the frog's neuromuscular junction". Nature 409 (6819): 479–84. doi:10.1038/35054000. PMID 11206537EM3D is first used for exposing cellular architecture at macromolecular resolution. 
    • Petersen JD, Chen X, Vinade L, Dosemeci A, Lisman JE, Reese TS (December 2003). "Distribution of postsynaptic density (PSD)-95 and Ca2+/calmodulin-dependent protein kinase II at the PSD". J. Neurosci. 23 (35): 11270–8. PMID 14657186EM3D is used to examine the architecture of the postsynaptic density at brain synapses. 
    • Ress, D., Harlow, M.L., Marshall, R.A., and McMahan, U.J. (2003). "Optimized Method for Isodensity Surface Models Obtained with Electron Microscope Tomography Data". Proceedings of the 25th Annual International Conference of IEEE. pp. 774-777EM3D's method for creating optimal isodensity surface models is described. 

IMOD

IMOD is a set of image processing, modeling and display programs used for tomographic reconstruction and for 3D reconstruction of EM serial sections and optical sections. The package contains tools for assembling and aligning data within multiple types and sizes of image stacks, viewing 3-D data from any orientation, and modeling and display of the image files. It includes a complete graphical user interface for generating tomograms, combining tomograms from tilt series taken around two axes, and stacking tomograms from serial sections.
  • Support: Operating systems: Linux, Windows, Mac OS X Image format support: MRC, TIFF
  • Cost: Free/Open Source, GPL
  • Primary Publication to Cite:
    • Kremer JR, Mastronarde DN, McIntosh JR (1996). "Computer visualization of three-dimensional image data using IMOD". J. Struct. Biol. 116 (1): 71–6. doi:10.1006/jsbi.1996.0013. PMID 8742726. 
  • Additional References:
    • Mastronarde DN (May 2008). "Correction for non-perpendicularity of beam and tilt axis in tomographic reconstructions with the IMOD package". J Microsc 230 (Pt 2): 212–7. doi:10.1111/j.1365-2818.2008.01977.x. PMID 18445149. 
    • Mastronarde DN (December 1997). "Dual-axis tomography: an approach with alignment methods that preserve resolution". J. Struct. Biol. 120 (3): 343–52. doi:10.1006/jsbi.1997.3919. PMID 9441937. 

protomo

Protomo is a suite of programs and shell scripts primarily developed for electron tomography. It offers routines for preprocessing micrographs, CTF-correction of images of untilted and tilted specimens, marker-free alignment of tilt series, and 3D reconstruction, besides some general image processing functionality.
  • Support: Operating systems: Linux Image format support: Most formats
  • Cost: Free
  • Primary Publication to Cite:
  • Additional References:
    • Winkler H, Taylor KA (February 2006). "Accurate marker-free alignment with simultaneous geometry determination and reconstruction of tilt series in electron tomography". Ultramicroscopy 106 (3): 240–54. doi:10.1016/j.ultramic.2005.07.007. PMID 16137829. 
    • Winkler H, Taylor KA (July 2003). "Focus gradient correction applied to tilt series image data used in electron tomography". J. Struct. Biol. 143 (1): 24–32. PMID 12892723. 
    • Taylor KA, Tang J, Cheng Y, Winkler H (December 1997). "The use of electron tomography for structural analysis of disordered protein arrays". J. Struct. Biol. 120 (3): 372–86. doi:10.1006/jsbi.1997.3932. PMID 9441940. 

PyTom

PyTom is a python-based package for tomogram analysis. It supports tasks such as particle localization and identification by template matching, subtomogram averaging, and subtomogram classification. The package is open source, does not rely on any commercial software, and is platform-independent. The implementation in python should allow easy scripting for specific tasks.

RAPTOR

Robust Alignment and Projection Estimation for Tomographic Reconstruction (RAPTOR) is a free available software to align raw stacks obtained from electron microscopes for tomographic purposes. It is intended to automatically obtain a full-precision alignment comparable to the one obtained with extended manual intervention. Fiducial particles are needed in the image for the alignment. It has been designed to be compatible with IMOD software, so results can be checked with the usual IMOD tools for alignment and reconstruction.
  • Support: Operating systems: Linux Image format support: MRC
  • Cost: Free
  • Primary Publication to Cite:
    • Amat F, Moussavi F, Comolli LR, Elidan G, Downing KH, Horowitz M (March 2008). "Markov random field based automatic image alignment for electron tomography". J. Struct. Biol. 161 (3): 260–75. doi:10.1016/j.jsb.2007.07.007. PMID 17855124. 

SerialEM

SerialEM is a program to acquire tilt series for electron tomography on Tecnai and newer JEOL microscopes. It uses an approach based on prediction of specimen position during the tilt series from the position at previous tilts. With this method, it achieves both the robustness of the older approach to tilt series acquisition (track and focus at every tilt) and the speed of the newer precalibration approach. It provides a complete interface for camera control and image acquisition, viewing, and saving. It includes a low dose mode for tracking and focusing away from the area of interest, energy filter control, acquisition of tilt series using a montage of overlapping frames, and a navigator module for mapping the grid and returning to selected locations. It supports Gatan, Tietz, FEI, AMT, and some Direct Electron CCD cameras.
  • Support: Operating systems: Microsoft Windows Image format support: MRC
  • Cost: Free for academic use
  • Primary Publication to Cite:
    • Mastronarde DN (October 2005). "Automated electron microscope tomography using robust prediction of specimen movements". J. Struct. Biol. 152 (1): 36–51. doi:10.1016/j.jsb.2005.07.007. PMID 16182563. 

TOM Toolbox

The Tomography Toolbox is a collection of functions that extend the capability of the MATLAB (+ Image Procesing Toolbox) numeric computing environment. The toolbox supports a wide range of functions for tomography.
  • Automated data acquisition procedures have changed the perspectives of electron tomography (ET) in a profound manner. Elaborate data acquisition schemes with autotuning functions minimize exposure of the specimen to the electron beam and sophisticated image analysis routines retrieve a maximum of information from noisy data sets. ‘TOM software toolbox’ integrates established algorithms and new concepts tailored to the special needs of low dose ET. It provides a user-friendly unified platform for all processing steps: acquisition, alignment, reconstruction, and analysis. Designed as a collection of computational procedures it is a complete software solution within a highly flexible framework. TOM represents a new way of working with the electron microscope and can serve as the basis for future high-throughput applications.
  • Support: Operating systems: Linux, Microsoft Windows Image format support: EM,MRC,Spider
  • Cost: Free
  • Primary Publication to Cite:
    • Nickell S, Förster F, Linaroudis A, et al. (March 2005). "TOM software toolbox: acquisition and analysis for electron tomography". J. Struct. Biol. 149 (3): 227–34. doi:10.1016/j.jsb.2004.10.006. PMID 15721576. 

TomoJ

TomoJ is a Java plug-in for ImageJ to perform tomographic reconstruction using ART, SIRT and WBP algorithms. It includes free reference alignment procedures in addition to standard cross-correlation methods in a friendly user interface.

TxBR

Tomographic reconstruction from large-format electron microscope data requires special procedures to handle geometric distortions arising from electron optics as opposed to light-ray optics. In particular, electrons travel in curvilinear paths through the sample, and defocus and other aberrations can have significant effects. TxBR handles geometric nonlinearities associated with charged-particle optics, distortion due to sample warping, and transform sets associated with non-standard modes of data collection. In addition, TxBR makes provision for marker-free alignment and specialized montaging for tomography of serial sections.
  • Support: Operating systems: Linux, Windows (≥ XP), Mac OS X (PowerPC and Intel) Image format support: MRC
  • Cost: Free
  • Primary Publication to Cite:
    • S. Phan, A. Lawrence (2008). "Tomography of Large Format Electron Microscope Tilt Series: Image Alignment and Volume Reconstruction". Congress on Image and Signal Processing, Vol. 2. pp. 176-182. 
  • Additional References:
    • Lawrence A, Bouwer JC, Perkins G, Ellisman MH (May 2006). "Transform-based backprojection for volume reconstruction of large format electron microscope tilt series". J. Struct. Biol. 154 (2): 144–67. doi:10.1016/j.jsb.2005.12.012. PMID 16542854. 

UCSF Tomography

UCSF Tomography is an integrated software suite that provides full automation from target finding, sequential tomographic data collection, to real-time reconstruction for both single and dual axes as well as automated acquisition of random conical data sets. This software was implemented based upon a novel approach in which the compustage tilting is modeled as geometric rotation. The spatial movement of the sample as a result of stage tilting can be predicted based upon previously collected tomographic images. Therefore, there is no need to collect tracking and focusing images during the entire tomographic data collection. A significant dose saving can thus be achieved and is critical in collecting cryo tilt series. Real-time reconstruction is achieved by calculating a weighted back-projection on a small Linux cluster (five dual-processor computer nodes) concurrently with the UCSF tomography data collection running on the microscope’s computer, and using the fiducial-marker free alignment data generated during the data collection process. The real-time reconstructed 3D volume provides users with immediate feedback to fully asses all aspects of the experiment ranging from sample choice, ice thickness, experimental parameters to the quality of specimen preparation. To facilitate dual-axis tomographic data collection, a hierarchical scheme for target finding and relocation after specimen rotation was developed and integrated with the predictive data collection and real-time reconstruction, allowing full automation from target finding to data collection and to reconstruction of 3D volumes with little user intervention. An on-site scheme was developed for random conical data collection where tracking and focusing are performed at the same location as the final conical tilt images. Lower magnifications combined with short exposure are used to substantially reduce dose and to allow larger tilt steps. The system also includes a feature for montaging untilted images to ensure that all of the particles in the tilted image may be used in the reconstruction.

FEI Xplore3D™ Tomography Suite

Xplore3D provides a complete solution for 3D tomographic acquisition, reconstruction, and visualization into one integrated package. The advanced capabilities include batch acquisition, dual-axis tomography, low-dose imaging, STEM tomography, energy filtering, and hardware acceleration for reconstruction. Batch scheduling permits unattended overnight data acquisition from multiple grid positions. Accurate, interactive alignment routines can use cross-correlation (no markers needed), bead tracking, or general feature tracking. Advanced reconstruction techniques include weighted back-projection, ART, and SIRT. Xplore3D includes a post-alignment and reconstruction module, Inspect3D.
  • Support: Operating systems: Windows XP, Image format support: most image formats
  • Cost: Price available upon request, Perpetual right-to-use license
  • Primary Publication to Cite:
    • R.H.M. Schoenmakers, R.A. Perquin, T.F. Fliervoet, W. Voorhout, H. Schirmacher (July 2005). "New software for high resolution, high throughput electron tomography". Microscopy and Analysis 19 (4): 5-6. 
  • Additional References:
    • Li Peng, Sergey Ryazantsev, Ren Sun, Z. Hong Zhou (January 2010). "Three-Dimensional Visualization of Gammaherpesvirus Life Cycle in Host Cells by Electron Tomography". Structure 18 (1): 47-58. doi:10.1016/j.str.2009.10.017. PMID 20152152. 
    • Linda F. van Driel, Jack A. Valentijn, Karine M. Valentijn, Roman I. Koning, Abraham J. Koster (November 2009). "Tools for correlative cryo-fluorescence microscopy and cryo-electron tomography applied to whole mitochondria in human endothelial cells". European Journal of Cell Biology 88 (11): 669-684. doi:10.1016/j.ejcb.2009.07.002. PMID 19726102. 
    • Laura van Niftrik, Willie J.C. Geerts, Elly G. van Donselaar, Bruno M. Humbel, Alevtyna Yakushevska, Arie J. Verkleij, Mike S.M. Jetten, Marc Strous (March 2008). "Combined structural and chemical analysis of the anammoxosome: A membrane-bounded intracytoplasmic compartment in anammox bacteria". Journal of Structural Biology 161 (3): 401-410. doi:10.1016/j.jsb.2007.05.005. PMID 17604181. 

Subvolume averaging[edit]

Dynamo

Dynamo is a software package for subtomogram averaging of Cryo-EM data. It is intended to provide users with big flexibility when adding new algorithms into standard procedures and adapting them for different computing environments as desktops, multicore machines, (multi)GPUs or clusters of CPUs.
  • Support: Operating systems: Linux, Mac OS, Windows Image format support: .em, .spi, .mrc
  • Cost: Free for academic use, GPL / BSD
  • Primary Publication to Cite:
    • Castaño-Díez D, Kudryashev M, Arheit M, Stahlberg H (2012). "Dynamo: A flexible, user-friendly development tool for subtomogram averaging of cryo-EM data in high-performance computing environments.". J Struct Biology (3). doi:http://dx.doi.org/10.1016/j.jsb.2011.12.017 

Jsubtomo

Jsubtomo is an open source software package based on Bsoft for averaging of tomographic sub-volumes. It includes tools for locating sub-volumes in tomograms using constrained cross-correlation, missing wedge-weighted averaging and refinement. Initial estimate of particle orientation can be easily included to constrain refinement. Python scripts are available for parallel processing and iterative refinement.
  • Support: Operating systems: Linux, Mac OS, Windows Image format support: Most, including .map, .mrc, .em, .spi, .img, .pif
  • Cost: Free
  • Written In: C
  • Primary Publication to Cite:
    • Huiskonen JT, Hepojoki J, Laurinmäki P, Vaheri A, Lankinen H, Butcher SJ, Grünewald K. (2010). "Electron cryotomography of Tula hantavirus suggests a unique assembly paradigm for enveloped viruses.". J Virology 84 (10): 4889-97. doi:10.1128/JVI.00057-10 

PEET

PEET is an open-source package for subvolume alignment, averaging, and classification. PEET is most easily used in conjunction with IMOD.
  • Support: Operating systems: Linux, Mac OS-X, Windows Image format support: .mrc
  • Cost: Free, GPL
  • Written In: Matlab, C, C++
  • Primary Publication to Cite:
    • Nicastro D, Schwartz C, Pierson J, Gaudette R, Porter M, McIntosh J.R. (2006). "The molecular architecture of axonemes revealed by cryoelectron tomography.". Science 313 (5789): 944-948. doi:10.1126/science.1128618 

Mass measurements[edit]

MASDET

A fast and user-friendly multiplatform software for mass determination by dark-field electron microscopy. MASDET offers several subroutines for the main mass analysis steps, namely image display and selection of regions of interest (ROI), mass evaluation and data analysis. Two program-modes constitute the core procedures for mass determination: (i) the program-mode AREA determines the mass-per-area of sheet-like structures (e.g., protein S-layers, thin organic and inorganic films) and the mass-per-box for globular structures (e.g., single macromolecules, globular assemblies, organic/inorganic nanoparticles), and (ii) the program-mode FILAMENT determines the mass-per-length for filamentous structures (e.g., intermediate filaments, DNA-protein complexes, tobacco mosaic virus, nanowires) in individual ROIs. The statistical analysis of the mass data in individual ROIs contains graphical data display (histograms and XY-plots) and allows up to 10 Gaussian curves to be fitted. The dark-field micrographs can also be recalculated to a mass-thickness profile and/or mass-thickness map using data from Monte Carlo simulations.