Image Distortion Field of Gatan US4000 CCD Camera on Tecnai F20

Chen Xu

$BrandeisEM: doc/en_US.ISO8859-1/articles-xml/Distortion-Field-for-US4000-on-F20/article.xml 2 2013-01-28 05:37:40 xuchen Exp$

It might be also useful to have distortion field for a non-GIF camera, specially for tomography data. This document provides information about the distortion field measurement of our Gatan US4000 CCD camera on Tecnai F20.

The specimen used for this testing data is a 1/4 C-flat grid with 10nm Au particles dispersed on it densely. 2/2 Quantifoil or 2/2 C-flat grid doesn't give sufficient area among the holes for camera view at 14500X. I have more confidence with this rigid sample, compared to plastic sections.

This is basically for Cristian who collects data on Tecnai F20 using Gatan US4000 CCD, mainly at the magnifications of 14,500X and 19,000X, where the pixelsize on specimen is around 1nm; when binning of camera is set to 2.

US4000-14500.idf for mag 14,500X
US4000-19000.idf for mag 19,000X

Table of Contents
1 Distortion Field Measuring Data Collection
2 Analysis of the Data

1 Distortion Field Measuring Data Collection

The data condition:

Date = Jan 28, 2013
H.T. = 200kV
Gun lens = 3
Ext.Vol. = 3950V
C2 aperture = 100um
Obj. aperture =  40um
Spotsize = 3

2 Analysis of the Data

The complete screen output for 14.5kX processing is as below.

For 19000X