Juno Perijove 56, November 22, 2023 Options

[mcaplinger]

Some of the images have been posted on missionjuno.

You will immediately notice that there is something weird about them. Yes, we know about this, and I'll say more about it when I can. In the meantime, anything people can do to process them would be appreciated. I've had some success using https://github.com/chunglabmit/pystripe

[Brian Swift]

My current thought is that when taking images that are not "cadence constrained" (eg just Jupiter, not Io) would be to acquire "HDR" image sequences. Take a normal exposure image, followed as quickly as possible by a 3x or 4x longer exposure, and possibly followed by a 3rd even longer exposure. The idea being that the longer exposures will move the signal up out of the noise. And "exposure fusion" post processing could be used to recover useful imagery from the darker areas currently dominated by noise.

WRT companding. Probably want to eventually shift table (so bterm0 is about ~320 larger?), so lower ~100 companded values aren't going utilized.

[mcaplinger]

WRT companding. Probably want to eventually shift table (so bterm0 is about ~320 larger?), so lower ~100 companded values aren't going utilized.

The bterms are only 8 bits, unfortunately. We did not anticipate this particular problem.

[StargazeInWonder]

I just took Bjorn's approximately true color picture of Io from PJ 55, and tried synthesizing a blue channel from the green and red only. I subtracted half the red image from the green, then made that result about 1.5x brighter and used that as the blue. At a casual glance, this comes out looking almost indistinguishable from the original. So, unless the raw blue was used to help produce the green and/or red in that image, there's no doubt that we'll get something aesthetically great if we end up with only red and green data. But, it will be a fiction even if a pretty one and on the off-chance that there's actually an especially green or especially blue feature there (like a sulfur dioxide plume), it'll come out skewed.

I don't know what the chances are that the blue data would come back with some lines or pixels intact. As long as this image covers terrain seen from similar geometry in previous Juno imagery, there's the possibility of using that information to evaluate the veracity of such data in this imagery, and "ground truth" even the rare reliable blue pixel. There's potentially a detective story here to recover real color information at lower resolution.