Dear Jacob
There is a strong tradition of profile fitting in integration - for 3D profile fitting I would feel that this is the best place to start:
http://scripts.iucr.org/cgi-bin/paper?S0021889888007903
(Kabsch, 1988)
This was about processing data from a multiwire detector which behaved a lot like the pixel array detectors of today re: fine slicing & big (ish) pixels
The assumption of a Gaussian form is however a dangerous one, as we are certainly seeing "fine structure" in spots these days.
I am certain you will get many other references pointed your way, going back to e.g. Diamond 1969 on the profile fitting for point detector data
Best wishes Graeme
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From: CCP4 bulletin board [[log in to unmask]] on behalf of Keller, Jacob [[log in to unmask]]
Sent: 10 February 2016 14:24
To: ccp4bb
Subject: [ccp4bb] Spot Integration Vs Fitting
Dear Crystallographers,
As I understand it, all integration software uses measured intensities rather than fits thereof. Wouldn't it be better in the case of (very) fine phi slicing to start using 3D gaussian fits to the spots, perhaps even with outlier rejection? I would think a fit to, say, 10 samples of a Gaussian would be more precise than summing the intensities.
Perhaps a lot of datasets have non-Gaussian distribution?
JPK
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Jacob Pearson Keller, PhD
Looger Lab/HHMI Janelia Research Campus
19700 Helix Dr, Ashburn, VA 20147
email: [log in to unmask]
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