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The Big One, My latest (and last for a while!) mosaic...
ugordan
post Dec 6 2007, 09:56 AM
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QUOTE (Ian R @ Dec 6 2007, 12:52 AM) *
Unfortunately, it seems as if the centre tile is over-exposed to the point of saturation, although I haven't yet looked at the PDS release to see if that is indeed the case.

This data is not yet available on the PDS (scheduled for January 2008), but unfortunately all evidence points out to the actual raw data being overexposed as well. How they couldn't figure out a correct exposure for a low phase view of a well characterized target puzzles me (all the more because gaseous objects don't tend to display great brightness variations vs. phase angle). The same issue was present in the very first huge Saturn mosaic, it was only the second big one which got the exposures right (The Greatest Saturn Portrait... Yet).

It's a shame because this particular view shows a vantage point pretty similar to what can be observed from Earth and it would make for a nice comparison to those cool Hubble views.


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tedstryk
post Dec 6 2007, 12:26 PM
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Great work with the data available! It is surprising that it is so overexposed....For the central disk, it is hard to think of a reason. I have my fingers crossed that it is another quirk of the "raws," and that the overexposure is not real.


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ugordan
post Dec 6 2007, 12:52 PM
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QUOTE (tedstryk @ Dec 6 2007, 01:26 PM) *
I have my fingers crossed that it is another quirk of the "raws," and that the overexposure is not real.

The fact CICLOPS only released the bottom portion of the mosaic as Ian said suggests otherwise, unfortunately. It should be noted that a few filters are not overexposed, but IIRC they are in the infrared region.


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ugordan
post Dec 23 2007, 11:02 PM
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Here's a rather quick mosaicking attempt at the calibrated version of the mosaic (just hit PDS) (2 megabytes full res view): click here

It's poorly registered, but it shows the original data is indeed overexposed as I suspected.


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