Shutter Speed vs Aperture Phenomena

[DeeDoubleYou]

These two shots were taken with a S5 IS at its shortest focal length, both at ISO 80 and Auto WB. I was experimenting with various combinations of aperture values and shutter speed times. The curious thing to be noticed is the image of the moon and how it takes on a star-like quality with a higher aperture value. I would greatly appreciate if anyone could shed some light on my night shots. The first shot is at f2.7, 2.5sec and the second at f8.0, 15sec.

[Wilt]

You are seeing the result of the diaphram blades of the lens, and the diffraction pattern created. Lenses which have more blades can more closely approximate a circle, so they do not have this appearance in photos taken at same aperture as your photo. Because diffraction effects are stronger as the aperture is reduced in size, you see the effect as the lens stops down.

[deadpass]

this is replicatable with SLR lenses too, but you generall have to be stopped down pretty far
f/11-f/16 or so.

[Hermeto]

In addition to Wilt’s explanation: there is also a correlation between the number diaphragm blades and the number of star points..
Every lens will have twice as many star points (diffraction spikes) as the number of diaphragm blades.

However, if the lens has an even number of blades, the two points for each blade will be superimposed on each other, creating one bright star point for each blade.
If the lens has an odd number of blades, both points for each blade will be visible, but they’ll be dimmer.

[DeeDoubleYou]

Thanks guys. What can I do to get the same shot of the palm trees, but with a more realistic looking moon?

[tzalman]

Use HDR techniques (search, a ton of info here) to blend two exposusures - one like above and one for the moon.

[S-Man]

Yeah, I'd say use an HDR process. Take a pic metered for the moon and another one for the trees. Then layer and *Shazam!* Post card.

[DeeDoubleYou]

Awesome, I'll see how it goes!! Merry Christmas!