Computed tomography

Computed tomography (CT) provides an invaluable non-destructive technique for visualising the external and internal structure of objects in 3D.

The technique is becoming increasingly used to study palaeontological, zoological, mineralogical, entomological and botanical specimens. The Natural History Museum is the only museum to possess state-of-the-art micro-CT and nano-CT scanners and is uniquely placed to carry out such research.

CT at the Museum

The Museum uses three forms of tomography. The choice of instrument depends on the size and density of a specimen:

  • Reflection micro-CT
    Specimen size: 3-250mm diameter or height
    Resolution: 3-5µm or 1/2000th of the specimen’s diameter or height, whichever is the larger value
  • Transmission micro-CT
    Specimen size: 2-5mm diameter or height
    Resolution: 3-5µm or 1/2000th of the specimen’s diameter or height, whichever is the larger value
  • Reflection nano-CT
    Specimen size: less than 2mm in diameter
    Resolution: 0.2-2μm
  • Still image taken from a micro-CT scan of Pocillopora coral
    Basic principles of computed tomography (CT)

    An introduction to computed tomography, including what the process involves and what determines the resolution of a scan. Find out why CT scans lend themselves to quantitative analysis of structure and geometry.

  • Still image taken from a micro-CT scan reconstruction of a mummified cat
    Micro-CT

    Discover the many applications for computed tomography. Learn about micro-CT at the Museum, including details of our state-of-the-art scanner, our micro-CT software workshops and how to arrange a scan of your specimens.

  • 3D volume of a bryozoan prepared using reflection nano-CT
    Reflection nano-CT

    Learn about reflection nano-CT and the Museum's Gatan X-ray Ultra Microscope instrument.

CT contact details

Dr Farah Ahmed

Tel: +44 (0)20 7942 5157

Email

Still image taken from a micro-CT scan of an ammonite fossil
Micro-CT software workshops

The Museum offers training in commonly used micro-CT software packages. Find out about the regular workshops and how to book a place.

Where to go for more information about CT

Forums
  • X-Tek CT users group
  • NHM CT collective (suitable for less technical users)
CT-related websites

Copyright

The Museum retains copyright on all scans of our specimens. Their use is subject to the Museum’s copyright policy on images. All Museum specimen scans will be archived and can be obtained with permission from the collection curator. Stereolithography and 3D printing are not permitted without prior permission from the curator.