http://www.planetary.org/news/2007/0930_Ma...ate_Spirit.html

Interesting news regarding calibration:

It seems that some of the imaging gurus here have not just re-invented the wheel, but improved on it substantially!

I for one, hope that Jim and his team are successful. I don't want to mess around with extra processing, or wait for others to post a view that can be useful. We have some really awesome people here, but let us take all the informed help we can get.
Go Jim, go.

Well I've already re-invented the wheel as best I can, but this would still be most welcome. Applying this step to the stretched jpegs is not ideal, having JPL do it first would work much better.

James

Wow... imagine having calibrated jpegs instead of raws. They could still be histogram stretched linearly as they are now, but additional info on what luminance the lowest and highest DNs are exactly so we could reconstruct the original dynamic range from 8bit jpegs, while retaining a good portion of it. The actual image quality per jpeg would go up because the algorithm wouldn't have to encode the flatfield noise as actual data.

I'd almost rather have the stretching data than the fixed jpgs, but I'll gladly take either one.

Just flat fielded JPG's is more than we could possibly expect and would be a massive improvement - so all kudos to Jim for trying to get that done.

Yes, if they go ahead with this one, they'll be setting standards once again. Standards that will be tough to follow for others.

Now if they could just reduce or eliminate the compression used in the jpegs as well...

I suppose that the key here would be establishing a legal moratorium on publications by non-team-members based upon those images for the first year or two following release.

No - I don't agree they should eliminate the compression. That's the point of them - they're quick-look, rough and ready imagery. There SHOULD be a difference between this stuff and the calibrated product that is used internally. No legal moratorium, just nice JPG's with some RAD IMG's 6 months later. It's a system that works and in some ways is self policing.

Besides, keeping JPEGs at a reasonable compression level (so that it doesn't trash all detail) saves a load of space over PNGs. Let's not get greedy here. Flatfielded and radiometrically calibrated stuff is more than anyone can really hope for. It's icing on the cake.

Sounds pretty much at odds with the US Constitution. You can hide private information all you want, but you can't stop people from talking or writing about factual public information.

Well... copyright protections are not at odds with the Constitution. And I don't mean to say that the images are copyrighted, just to point out that protecting photographs from misappropriation is legal with the usual caveats. I don't know what side of 'fair use' using copyrighted photos in academic papers would fall on. I know you can excerpt copyrighted texts.

Phil Stooke would probably know, since his maps are debatably photographs and are published in copyrighted books.

I always remember this passage from 17 USC § 105, ever since I got that "proud to be an American" feeling when I saw it posted above a copier in the Bodleian Library, next to a passage on the restrictions imposed by Crown Copyright.


Unfortunately, most NASA work is done under contract, rather than by government employees, and is therefore subject to some form of copyright protection.

Steve M

The science data is, however, public domain after that 6 month period. Not copyright can or is held over it. Where a copyright CAN be held is over an 'original work' - which any mosaic can technically be said to be.

Doug