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View Full Version : Weird pattern seen in photo




PkennethV
Aug 1, 2008, 04:13 PM
This is at 100% magnification using Aperture's Loupe. Does anyone know what the maze-like pattern is showing in the middle (and more clearly towards the right side)? The this is a shot of an SB-800 pointing towards the camera.
http://img383.imageshack.us/img383/6624/picture1xa4.jpg

Here's the same pic zoomed out a little bit.
http://img166.imageshack.us/img166/6954/picture3bf1.jpg

This isn't a serious shot anyways -- just playing around so it's no big deal, but I'm just curious what that is/is caused from.



WillJS
Aug 1, 2008, 04:15 PM
Probably just how the computer is rendering the image.

ChrisA
Aug 1, 2008, 04:23 PM
For whatever reason I don't see the image. It did not make it all the way to my screen so I'm really guesing. But from what you say it could be a Moire pattern.

What you may have are two sets of grids are similar scales. One set of grid is the pixels in the sensor and the other is fine detail in the subject.
http://en.wikipedia.org/wiki/Moir%C3%A9_pattern
See the example of the parrot phot on the above page.

leighonigar
Aug 2, 2008, 11:14 AM
It's some kind of demosaicing artefact I guess. See http://www.cambridgeincolour.com/tutorials/camera-sensors.htm there's a paragraph on it. You've got maze-like artefacts.

Edit - this is interesting too http://kammagamma.com/how-we-test/demosaicing-and-false-colors-test

pinktank
Aug 2, 2008, 05:13 PM
it's probably how a camera renders lights together, part of the beyer output perhaps