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Defocus-gradient corrected back-projection

Jensen, Grant J. and Kornberg, Roger D. (2000) Defocus-gradient corrected back-projection. Ultramicroscopy, 84 (1-2). pp. 57-64. ISSN 0304-3991. doi:10.1016/s0304-3991(00)00005-x.

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Three-dimensional reconstructions of icosahedral viruses from cryoelectron microscope images have reached resolutions where the microscope depth of field is a significant resolution-limiting factor. An analytical treatment presented here shows how the depth of field limitation can be understood as an envelope function which gradually attenuates the signal, starting well before the numerical depth of field is actually reached. A simple modification to the well-known back-projection reconstruction algorithm is described, called the defocus-gradient corrected back-projection, which computationally corrects for the contrast transfer function along a defocus gradient. Computer simulations demonstrate how the algorithm effectively eliminates the depth of field limitation.

Item Type:Article
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Jensen, Grant J.0000-0003-1556-4864
Additional Information:© 2000 Elsevier. Received 2 September 1999, Revised 20 December 1999, Available online 15 June 2000. G.J.J. was supported by a Medical Scientist Training Program grant (GM07365) provided by the National Institute of General Medical Science at the National Institutes of Health. This research was supported by National Institutes of Health Grant AI21144 to R.D.K.
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Subject Keywords:Data processing; Image processing; Three-dimensional reconstruction
Issue or Number:1-2
Record Number:CaltechAUTHORS:20181213-110052503
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Official Citation:Grant J Jensen, Roger D Kornberg, Defocus-gradient corrected back-projection, Ultramicroscopy, Volume 84, Issues 1–2, 2000, Pages 57-64, ISSN 0304-3991, (
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:91764
Deposited By: George Porter
Deposited On:13 Dec 2018 22:23
Last Modified:16 Nov 2021 03:44

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