The good news is ESO is using science in evaluating whether the extended halo is real or not, instead of a subjective yes or no response based on looking at a pretty picture.
Their emphasis is on the noise in the background rather than the image itself.
The bad news is my processing efforts are hindering their efforts in making that evaluation.
I am becoming aware of the considerable differences in how amateurs and professionals process images.
Olivier Hainaut from ESO wrote...
Quote:
....Also, you have quite strongly smoothed the background with some clever noise reduction algorithm.
For us, that's a problem, as these algorithms tend to be non linear (i.e. if a star is 2x brighter than another one in the input, it will not be exactly 2x brighter in the output), and as the error analysis is screwed up ( *all* our measurements always come with error bars; to estimate these, we need a careful and detailed analysis of the noise, which the smoothing affects). So, definitely great for a nice image! dealing with the little glitches in the CCD would make it perfect.
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This was the second image submission to ESO where I took pains to minimize the effects of noise smoothing.
Evidently a mild degree of wavelet processing in PI with the noise reduction option "on" was enough to wreck ESO's attempts in evaluating the noise in the regions as shown in the attachment.
What I suspect ESO were investigating is the amount of Poisson noise in the region of interest. This is "good noise" related to the statistical variation of real data. If "bad noise" or Gaussian noise related to factors such a read out noise and noise produced by dark and flat field subtraction dominates, then the halo is nothing more than an artefact that has been enhanced by processing.
The next submission if ESO are still prepared to tolerate me
, is an image where there has been no processing except stretching including the pixel mapping process.
Hopefully ESO will also provide more information on how they evaluate the background noise.
Incidentally the latest high resolution image is here.
http://members.iinet.net.au/~sjastro...olour_halo.jpg
Regards
Steven