A question regarding Fourier transform in electron microscop

AI Thread Summary
The discussion centers on the application of the Fourier transform in electron microscopy, specifically regarding the resolution of a 2-D array micrograph captured at a high magnification. The user seeks clarity on the spacing of the finest detail obtainable in the Fourier transform relative to the specimen. It is explained that the Fourier transform operates in the space of spatial frequencies, with the smallest frequency in the image being determined by the size of the image. The spacing between frequencies in the computed transform is also linked to the image size. For precise calculations, exploring discrete Fourier transform concepts is recommended.
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I have recorded a micrograph of a 2-D array at a magnification of 43,000x on my DE-20 digital camera, which has a 6.4 μm pixel size and a frame size of 5120 × 3840 pixels. This magnification is correct at the position of the camera. I then compute the Fourier transform of the image. What is the spacing of the finest detail (highest resolution Fourier Coefficient) that I can hope to obtain in the computed transform, with respect to the actual particle itself in the specimen plane? What is the spacing between points in the computed Fourier transform (with respect to the original object, i.e. the crystal)?

I feel confused about the Fourier transform. So any help will be welcome. Thanks in advance!
 
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Not sure this adresses your question, but the Fourier transform is not a function on ordinary space, it is a function on the space of (spatial) frequencies. The smallest frequency present in your image is 1/L where L is the size of your image (where "1" is some constant depending on conventions). The spacing between frequencies is also 1/L.
 
I suggest that you look up topics about discrete Fourier transform, there you can find how to calculate the finest possible resolution for the calculate object.
 
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