No, what I have seen in spirit and opportunity is this grid all over, but most notable in sky. Popped up on a slow download . I will forward original half n half. It is just a? On my part.
geomeo, that is interesting. Are you suggesting that are applying a standard grid pattern tamepering to the sky sections. If I remember correctly at some point Harry (I think) suggested that they reversed/rotated individual pixels in the image and if you could determine the sequence you could unravel the tampering.....
Imaging artefacts are based on heavily reduced or insufficient data being replaced by lossy pixels. Lossy pixels orientate to screen . They have no perspective or depth. A prime example can be found in images in this thread. Pixels always appear flat in orientation to the depth of the location. .... Big clue. Cheers
This should help (notice the grid mapping at the bottom of page in supplied link).
http://www.betterjpeg.com/lossless-rotation.htm
-- Edited by TheWatcher on Monday 22nd of October 2012 01:18:46 PM
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HENRI BERGSON, Matter and Memory
One has not only an ability to perceive the world but an ability to alter one's perception of it; more simply, one can change things by the manner in which one looks at them.