Almost every pro is familiar with the practice of including a calibration target in a test shot to get the color right or to help with processing decisions, or as a first step in color management. They might come close to guessing what this is...the caption reads "This view of the calibration target for the Mars Hand Lens Imager (MAHLI) aboard NASA's Mars rover Curiosity combines two images taken by that camera during the 34th Martian day, or sol, of Curiosity's work on Mars. This image was taken Sept. 9." The photo is by NASA/JPL-Caltech/Malin Space Science Systems, via space.com.
Mike
(Thanks to Stan Banos)
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A product of interest today:
(To see all the comments, click on the "Comments" link below.)
Featured Comments from:
John Igel: "I can't believe they included a Lincoln Penny on the calibration target. But that is no ordinary penny. Here is the rest of the story."
Mike adds: An excerpt from the link: "If you’re wondering why a U.S. penny was chosen—it does seem a bit random, right?—it's because geologists often put pennies next to rocks to show their relative size. The NASA scientists wanted to hat-tip the field of geology."
You gotta love the 1909 penny! A real hat-tip to tradition.
Posted by: Roger McDonald | Sunday, 07 October 2012 at 01:21 PM
I'm curious as to what that custom calibration target cost as compared to, say, X-Rite's ColorChecker Passport ... 10X? 100X? Gulp ... 1000X?
Posted by: Jeffrey Goggin | Sunday, 07 October 2012 at 01:44 PM
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.
http://nssdc.gsfc.nasa.gov/imgcat/hires/vl2_22a166.gif
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.
http://mars.spherix.com/spie2003/SPIE_2003_Color_Paper.htm
Posted by: Kevin Purcell | Sunday, 07 October 2012 at 02:03 PM
That's a 1909 Lincoln head BTW...
Posted by: Stan B. | Sunday, 07 October 2012 at 02:08 PM
life on mars ?
Posted by: hugh crawford | Sunday, 07 October 2012 at 03:09 PM
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.
Posted by: Rod Sainty | Sunday, 07 October 2012 at 04:11 PM
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.
Posted by: Walt | Sunday, 07 October 2012 at 05:32 PM
@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.
Posted by: Roger Moore | Sunday, 07 October 2012 at 07:35 PM
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.
Stephen
Posted by: Stephen S. Mack | Sunday, 07 October 2012 at 07:41 PM
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.
Posted by: B.J. Segel | Monday, 08 October 2012 at 12:16 AM
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?
Posted by: John McMillin | Monday, 08 October 2012 at 12:58 PM
Color calibration? Nope, those are the watercolors the rover took along to paint the landscape. And the penny is just for good luck.
Posted by: JonA | Monday, 08 October 2012 at 01:19 PM
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.
Posted by: Emily Cartier | Monday, 08 October 2012 at 07:35 PM
Wow! The eyes of Laura Mars. Great movie. Especially when playing "spot the microphone in the picture"
Posted by: jean-francois | Tuesday, 09 October 2012 at 10:36 AM
The penny is there just in case Curiosity comes across an ancient parking meter.
Posted by: Craig Norris | Tuesday, 09 October 2012 at 09:56 PM