Fast, spatially varying CTF correction in TEM.
نویسندگان
چکیده
We have developed new methods for contrast transfer function (CTF) correction of tilted and/or thick specimens. In order to achieve higher resolutions in cryo-electron tomography (CryoET), it is necessary to account for the defocus gradient on a tilted specimen and possibly the defocus gradient within a thick specimen. CTF correction methods which account for these defocus differences have recently gained interest. However, there is no global CTF correction method available to this date (to process the entire field-of-view at once) which can use different inverse filters, e.g. phase-flipping or Wiener filter, and which can do so within a reasonable time for realistic image sizes. We show that the CTF correction methods presented in this paper correctly account for the spatially varying defocus, can employ different inverse filters and are significantly faster (>50×) than existing methods. We provide proof-of-principle implementations of all the presented CTF correction methods online.
منابع مشابه
A fast algorithm for computing and correcting the CTF for tilted, thick specimens in TEM.
Today, the resolution in phase-contrast cryo-electron tomography is for a significant part limited by the contrast transfer function (CTF) of the microscope. The CTF is a function of defocus and thus varies spatially as a result of the tilting of the specimen and the finite specimen thickness. Models that include spatial dependencies have not been adopted in daily practice because of their high...
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عنوان ژورنال:
- Ultramicroscopy
دوره 118 شماره
صفحات -
تاریخ انتشار 2012