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Sunday, 07 October 2012


You gotta love the 1909 penny! A real hat-tip to tradition.

I'm curious as to what that custom calibration target cost as compared to, say, X-Rite's ColorChecker Passport ... 10X? 100X? Gulp ... 1000X?

NASA had problems with color calibration on Viking 1 and 2.

They included a color target in the Viking mission but published the initial series of images with incorrect color giving a traditional "red planet" look.


They used the color filter response curves to generate the initial color conversion. Then one of the technicians noticed that the orange cables on the top deck of Viking didn't look right in the images. They used that to color correct the images.

They were still having some issues with Pathfinder and beyond (the light varies in spectral response) in 2003.


That's a 1909 Lincoln head BTW...

life on mars ?

Mike, as a geologist I can verify the tradition of placing a coin on a rock prior to taking a close-up photograph of it.

However, nowadays, younger geologists without the same sense of tradition will often substitute something ephemeral, such as a felt-tipped pen.

A 1909 penny has class!

Those papers cited by Kevin Purcell sure are fun to read. Thanks, Kevin.

Victor Brennen may have designed it but I don't see his initials on the shoulder. With that resolution it could be hiding. NASA has a 1987 by 1986 or so rez image on their curiosity website. Can't remember which is more valuable the one with the initials or without. Certainly the one in this image is worth a couple of billion.

@Jeffrey Goggin:

The expensive part of just about anything on a Mars rover is shipping and handling. If they can shave off a few grams, using a custom target will pay for itself. They might also want to use a custom job if they want to capture specific spectral responses that aren't well covered by conventional targets. For example, I would expect NASA to have hyperspectral imaging capabilities in their cameras, so it might be useful to have patches with specific UV and IR characteristics- not something you'll find on a traditional X-Rite color checker.

Look at the photo carefully: is that Evard Munch's influence I see there?

(Hint to the artitically challenged: Google "The Scream".

With best regards.


I've been told archaeologists use pennies too. I once visited an excavation of some ancient pit houses here in Arizona and was surprised to see pennies scattered about the site. When I asked about it I was told, "We're finished with our research here and are going to cover this site back up. We left this year's pennies to let any future archaeologists who excavate this site know that we were here and when."
I'd hate to think that some future Mars archaeologists will conclude that Curiosity arrived in 1909.

It looks kinda brownish-red, to my eye. Maybe the calibrations haven't been done yet--- or is this a job for Ziggy Stardust and the Spyders from Mars?

Color calibration? Nope, those are the watercolors the rover took along to paint the landscape. And the penny is just for good luck.

Handspinners use coins too, tho not always a penny. We tend to do a lot of shots that range from macro to very macro. In some instances, you're looking to photograph something that's got details in the 15 micron range... so a penny is sometimes too big.

Wow! The eyes of Laura Mars. Great movie. Especially when playing "spot the microphone in the picture"

The penny is there just in case Curiosity comes across an ancient parking meter.

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