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Leinad,
That's the nub of the problem - at least for me...
If the PSF of the Airy Disk contains ALL the energy/ photons available from the star, then the maximum size of the star image can NEVER exceed this size....hence my laser pointer analogy.... there's never any illumination beyond a 10 x 10 box...so whatever the exposure the size should always be less than 10 x 10.
If you look at the profile data say for Star#1 and Star #2 (one is saturated the other is well exposed). The "max" diameter recorded for #1 is 20 pixel and for #2, 12 pixel, and the FWHM is 6 pixel v's 3.5 pixel.
Why, when the brighter star is over-exposed more does the "size" increase by 166%....Aah...the longer exposure collects the light from the outer reaches of the PSF curve...Hmmmm don't think so....
IVO,
The second comment you refer to - wasn't the Airy disk being drowned out, but the light in the extreme "wings" ie that last 6% of total energy being drowned in the background noise....
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