Ettention is a software package for tomographic reconstruction in electron tomography. It implements the algorithms simultaneous algebraic reconstruction technique (SART), simultaneous iterative reconstruction technique (SIRT) and a generic, block-iterative reconstruction algorithm. Ettention is written in C++ and internally uses OpenCL to run on a large number of high-performance computing.

The software supports single tilt, parallel projections for the use with conventional transmission electron microscopy data. Support for a combined tilt- and focal series for use in high-angle annular dark field scanning transmission electron microscopy (HA-ADF STEM) is provided via plugin. Also via plugin comes support for X-Ray laminography reconstruction.

Precompiled binaries are provided in the download section. The software can be operated from the command line or via an integration in the eTomo graphical user interface of the IMOD software package.


Ettention is distributed in both binary and source code distributions under an LGPL license. Ettention features a plugin concept and all plugins provided via this website are also provided via a LGPL license. It is allowed to develop plugins under commercial, closed source licenses and provide them separately from this website.


Ettention supports a generic block-iterative reconstruction algorithm with configurable block size. The special cases simultaneous algebraic reconstruction technique (SART) and sequential iterative reconstruction technique (SIRT) are also included. Weighted back projection (WBP) and tilt-focal algebraic reconstruction technique (TF-ART) are included via plugins.

Ettention provides support for parallel and perspective forward- and backprojections. The STEM plugin provides support for parallel projections with limited depth of field.

A number of projection iteration schemes are provided, including sequential access, random access and severeal subdivision schemes.

Supported Platforms

Ettention supports Windows, RedHat Linux and Ubuntu Linux. We recommend 64 bit operation systems because of the large memory requirements for high-resolution volumes, but 32 bit versions are provided as well.

Ettention requires an OpenCL backend. Supported OpenCL platforms including

  • NVidia GPU, preferentially Tesla
  • Intel Xeon Phi
  • x86 OpenCL
  • running ettention on AMD GPUs has not yet been tested, but might work