Posted: Sat Sep 08, 2007 2:14 am Post subject: Reply with quote
OP "mgmirkin"
Michael Mozina wrote:
If we're basing assumptions off of "artifacts," are the artifacts indicative of actual struct5ures, or are they simply artifacts that shouldn't be given significant weight? I guess it depends on how the images are generated, how much we trust the algorithms behind them, and what meaning we ascribe to the outcome images/movies...
Define "artifact" for me.
Hmm... How to define "artifact?" Hadn't really thought about defining it. I'm sure there's one around somewhere. I guess I was thinking in terms of so-called "camera artifacts."
Things that "appear" in images that aren't ACTUALLY there but rather are an artifact or signature left due to the specific process involved in taking the measurement. Or in some ways, it's the "noise" in an image, as opposed to "signal."
For example, some photographers take pictures in a dark room with a flash. They get back pictures of their friend, illuminated by the flash, and a number of "floating orbs." When the picture was taken, there were no "floating orbs" present. Some people say, wrongly, "well, those must be ghosts! Wooo..." however, analysis of the camera, and the environment yields further insight that the room was quite dusty, and some of the dust was extremely close to the lens. While the shutter was open, the light from the flash ricocheted off the dust and into the shutter before it closed, exposing the film with "floating orbs."
The orbs themselves did not exist. They were artifacts of the photographic process and the environment, and the distances and physics involved.
Likewise, another instance I recall reading about was when someone was taking videos around sunset, and had set their video camera to a slower shutter speed, to capture more light. When they watched the videos, they thought they'd discovered a new breed of multi-winged dragonfly-like insect that was quite long and wispy. In fact, what had happened was that they had video'd a rather normal bug, but the shutter had been opening and closing slowly enough on the slow shutter for the bug to have moved across the frame a good distance in one frame, then a good distance again in the next frame. And in the video playback, it appeared to be one very long weird insect, or even a swarm of such insects, when in fact it was only one or two.
So, my question is simply one of whether such artifacts can be created through whatever algorithm is used for processing running difference images. IE, could something that doesn't actually exist somehow be left as such an "artifact" in a heavily processed image or series of images, simply due to the way in which it's processed?
IE, is the "immobility" or "immutability" an artifact of how things are being processed? Does the immobility mean what we think it means about the structure of the sun? Or does it simply mean something about the process that took the image?
Hope that makes sense?
Not to say yea or nay to the interpretation or question the validity of the images or our level of faith in their quality. Just some fair introspective questions. Personally, I think the running difference movie is awesome. Just have had a few reservations about assuming it means what has been implied without knowing the process behind the creation of the image(s) and what they actually mean. Personally, I think it would be a rather cool coup d'etat if they do mean what's implied on the surfaceofthesun site... Smile
Cheers,
~Michael Gmirkin