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VPhot Effect of Signal Circle Radius graph

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onj's picture
Joined: 2010-07-25


I am wondering as the meaning Effect of Signal Circle Radius in the Measurement Details page in VPhot. Please see attached for a screen capture for my example.

I take the blue curve to be the SNR, with the SNR of 205 corresponding to my aperture radius of 7 pixels.

However, in the black curve, the Instrumental Magnitude of -7.653 lies outside the range of the y-axis values of from -9.0 to -12.0.

I wonder would it be possible to label each curve.



measurement details.jpg88.14 KB
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