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I uploaded an image and it's called neg195_scannereval_lowres.png Q) In this (scanned from film) image, what are the weird looking Fourier tiles indicative of? Also, should this question be in the EMAN2 section? I think that that region labelled B is normal but that A and C are strange, maybe film warping?
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I would like to put it here and ask the question attachment:e2scanner_image.png
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What are the weird looking Fourier tiles indicative of? A) Very nice example of warped film in the scanner. You are seeing the MTF of the scanner lens when out of focus. What type of scanner were you using, and did it have a mechanism for holding the film flat ? This data may still be usable with sufficient averaging (ie - if you average by ~2, you will push the first ring in the MTF to almost Nyquist). This is exactly the sort of effect e2scannereval.py is designed to detect.

Also, I'm puzzled by how you're editing this page. Only registered users can edit pages in the wiki, but I can't find your user information in the wiki registration ?

Q) In this (scanned from film) image, what are the weird looking Fourier tiles indicative of? Also, should this question be in the EMAN2 section? I think that that region labelled B is normal but that A and C are strange, maybe film warping?

attachment:e2scanner_image.png

A) Very nice example of warped film in the scanner. You are seeing the MTF of the scanner lens when out of focus. What type of scanner were you using, and did it have a mechanism for holding the film flat ? This data may still be usable with sufficient averaging (ie - if you average by ~2, you will push the first ring in the MTF to almost Nyquist). This is exactly the sort of effect e2scannereval.py is designed to detect.

Also, I'm puzzled by how you're editing this page. Only registered users can edit pages in the wiki, but I can't find your user information in the wiki registration ?

EMAN1/FAQ/e2scannereval_results (last edited 2009-04-22 14:42:55 by SteveLudtke)