<p>Flux/Flux_err is the signal to noise ratio of your flux measurement.</p>

CC BY-SA 4.0
2024-07-21T10:21:18.317Z
2024-07-21T10:21:18.317Z
ProfRob
<p>I have JWST images across 7 filters. I extracted sources by using SExtractor. How can I estimate the SNR of each source in each filter. Should I use flux/flux_err or use flux/background_rms. (flux and flux_err are in units of counts and background_rms is the value given by SExtractor) ?</p>

<observational-astronomy><photometry><james-webb-space-telescope><image-processing>
SNR (Signal to noise ratio) from image
Walker
# SNR (Signal to noise ratio) from image

(Asked by: username_0 on 2024-07-21)

I have JWST images across 7 filters. I extracted sources by using SExtractor. How can I estimate the SNR of each source in each filter. Should I use flux/flux\_err or use flux/background\_rms. (flux and flux\_err are in units of counts and background\_rms is the value given by SExtractor) ?

**Tags:** observational-astronomy, photometry, james-webb-space-telescope, image-processing


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## 1 answers

### Answer by username_1 on 2024-07-21. Score: 1

Flux/Flux\_err is the signal to noise ratio of your flux measurement.


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