Article Text

Download PDFPDF
Correction of uneven illumination (vignetting) in digital microscopy images
  1. F J W-M Leong1,
  2. M Brady2,
  3. J O’D McGee3
  1. 1Oxford University Nuffield Department of Clinical Laboratory Sciences, John Radcliffe Hospital, Oxford OX3 9DU, UK
  2. 2Medical Vision Laboratory, Oxford University Department of Engineering Science, Oxford, UK
  3. 3Oxford University Nuffield Department of Medicine, John Radcliffe Hospital
  1. Correspondence to:
 Dr F J Leong, NDCLS, L4 Academic Block, John Radcliffe Hospital, Oxford OX3 9DU, UK; 


Background: Many digital microscopy images suffer from poor illumination at the peripheries (vignetting), often attributable to factors related to the light path between the camera and the microscope. A commonly used method for correcting this has been to use the illumination of an empty field as a correction filter (white shading correction).

Aims: To develop an alternative shading correction method that does not require this additional image.

Methods/Results: This report outlines an alternative shading correction method that is based upon the intrinsic properties of the image, which are revealed through Gaussian smoothing. The technique can be implemented within Adobe Photoshop or other graphics editing software and works well with both haematoxylin and eosin and immunohistochemical images.

Conclusions: This technique provides an effective means of optimising digital microscopy image appearances for printing, image analysis, or telepathology.

  • vignetting
  • shading correction
  • digital microscopy
  • digital imaging
  • low pass filtering
  • telepathology

Statistics from

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.