Here is a better version of the night face of Pluto :



Fred

Definitely getting some features here Fred. Good work!

Edit: Looking at the positions within the system, I actually think this may be mostly scattered light rather than Charon-shine.

I tried enhancing the contrast a little more here as well.

Thanks a lot, Fred. Could you explain what you did? In addition to registering on the crescent of Pluto, did you attempt to remove the obvious scattered light that's mainly around the centre of each frame? As you go through the 180-odd frames, the crescent shifts around but the scattered light stays pretty much at a fixed position in the frames. But the positions scanned by the crescent aren't very uniform, so if you just average all the frames after registering you'd expect to see brighter and darker patches on the dark side due to the averaging of the scattered light. In particular, the lower-right part of the dark side never really gets into the scattered light, so that might explain why the lower-right part of the dark side is dark on your image.

What I'd do (if I had the time) would be to first produce a template for the scattered light (maybe by averaging some frames with the crescent removed), and then subtract that template (suitably normalized) from each frame, before registering on the crescent and doing the final average. "Suitably normalized" is the hard part here - but I wouldn't be surprized if there's an imageJ plugin to do that...

Yes I do agree with you. Charon is very dark compared to Pluto atmosphere's scattered light and the area where the details are visible is located on the limb near the Sun's direction : bottom right side. Charon's illuminated area is on the bottom left side of Pluto and we see nothing there.

I haven't tried yet but I think you could probably stack enough of the frames together to cancel out the crescent as noise and then you could use that as your dark frame. Might have a go at this today.

Edit: Well, it worked actually really well at taking out scattered optical rays but being 8bit jpgs, it made everything too smooth.



This was a stack of the 22 images on the 1st page. Maybe it would work better with more frames. Or maybe some preprocessing on the frames would benefit or mixing in preprocessed with unprocessed. Lots of options here still.

With the raw images, you could probably just readjust the stretching on the image and start seeing some features.

Edit 2: Also, here's the stacked frame I used for a dark frame, if anyone else wants to try.

 .7_Mkm_4x4_Pluto_IM____dark.tif ( 136.28K ) Number of downloads: 283

What I did :

1) download all images
2) convert them to FITS with Iris ( http://www.astrosurf.com/buil/us/iris/iris.htm )
3) make a master flat from all the images (I used a master bias made from a batch of 11 photos of short duration from "black" pictures of Nix, Hydra...)
4) process the FITS (remove offset, divide by flat)
5) align the resulting images (planetary registration)
6) stack the images (sigma median)

Then I saved the result in PSD format.

In Photoshop (CS2) :
1) resample the image by 400%
2) remove the borders with are crapy
3) play with the curves to get max details
4) enhance details with a local enhancement filter (see principle : http://www.cambridgeincolour.com/tutorials...nhancement.htm)
5) adjust curves again

Save and stop !

Fred

The New Horizons team is preparing for a big week at the AAS/DPS meeting with dozens of research report talks and posters, as well as a press briefing. Many new results will be announced. As a result there will be no Thursday captioned releases the weeks of Nov 2 and 9. There will however be a NASA news release summarizing major DPS highlights.

I'm worried the Charon shine imaging didn't work.

And there was the very welcome announcement of the successful trajectory adjustment toward the next target which for me was more than compensation for the absence of an image release that day.
https://www.google.co.uk/url?sa=t&rct=j...0p9l1jCYDAHbHpw




It was always a bit of a shot in the dark. For completeness it had to be tried.

I definitely wouldn't jump to that conclusion so fast.

Take this image for instance:


(click to enlarge)

Both the right and left images are from the exact same source but if you were to crop around the darker image on the left, there is no way you will be able to extract enough data to reach the version on the right. The raw files contain 16-times more data than this version or any of the files on SOC. Looking at the above linked image, I can almost guarantee we will have more to add to the Pluto map.

Groan....

The Charonshine images may work better if the black sky images are used in combination with the Pluto images. To properly use them would probably requires the pointing information for both the blank sky images and the Pluto images which the New Horizons team has but the image gurus don't. Maybe we will see some better results at the DPS conference.

Thanks a lot for the details, Fred. But what you've done to make the flat is still unclear to me - if you'd be willing to post the flat, well, that would be worth 1000 words...

you have the background noise


and the image with it removed


very quick based on the first 3 pluto images on the page
what's left is the JPG noise artifacts

Great news, that is what I will be looking forward to. Worth more than interminable discussions about the airspeed velocity of swallows in a Plutonian atmosphere...

8-13 November 2015

http://aas.org/meetings/dps47

--Bill