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How to find FWHM?

by bugra
Tags: aperture, fwhm, gaussian, photometry, stdev
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bugra
#1
Jan31-11, 10:21 AM
P: 2
Hi,
I've been searching on google for minutes but couldn't find out a consistent way so far. I mean, it seems everybody has something to say about it :)

My data consists of pixel values (ADU's). I am writing a script to obtain fwhm of seeing disk.

By definition of the gaussian curve, i should only calculate the standart deviation of these values theni get fwhm=stdev*2.355 .
Am I correct?

Or should i obtain a gaussian fit then i calculate fwhm as its name suggests?

Thanks in advance,
bugra
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EnumaElish
#2
Feb1-11, 08:53 PM
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If you do it both ways, and the answers are different, what does that tell you about the fitting algorithm that you used?
bugra
#3
Feb9-11, 07:03 AM
P: 2
for multiple sources on the same frame, should fwhm be same?

chemisttree
#4
Feb10-11, 10:31 PM
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How to find FWHM?

I would think the actual value of FWHM is less important than the rate of change near perfect focus.


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