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Posted by: djellison Jan 17 2006, 12:33 AM

http://pds-smallbodies.astro.umd.edu/missions/deepimpact/index.html

I'm always a fan of obscure data sets, so where best to start with the astonishing imagery of Deep Impact than with....

Impactor camera calibration images of M11

Well - I thought I'd start with the obscure

Doug

Posted by: djellison Jan 17 2006, 12:36 AM

Later on ( 2005/120 ) I think they must have run an impactor simulation - as they have the very rapid, smaller and smaller images of...well, where else would you practice but...SATURN

(I know - odd eh - but novel and interesting little pictures anyway)

These are the first and last images from the sequence.

Doug

Posted by: djellison Jan 17 2006, 01:10 AM

Just for a laugh - what I THINK are the 3rd, 4th, 5th, 6th and 7th from last images from the impactor. The last image is too blured, and the penultimate image is a partial product....

These 5 mosaic well, then it's a bit of a 'huh' few images, then it picks up again.

Doug

Posted by: djellison Jan 17 2006, 01:40 AM

Nest of images - probably nothing new compared to what was done back when they had dodgy JPG's out - but it still makes me go "Woo - data"

Doug

Posted by: djellison Jan 17 2006, 01:56 AM

And as for the high resolution visible - oh BOY was that puppy out of focus....these should be stars, and the second is the moon. REALLY bad.

Posted by: elakdawalla Jan 17 2006, 02:42 AM

Boy, you're quick! Got a wGet routine to share with us?

--Emily

Posted by: djellison Jan 17 2006, 08:33 AM

Well - as they just have a bunch of .tar's on a webpage, I used FlashGet with Free Download Manager in Firefox and asked it to grab the lot

There's plenty-gig's of it, and my ISP will start FedEx'ing horses heads if I'm not carefull for the rest of this month

Doug

Posted by: edstrick Jan 17 2006, 09:41 AM

The earliest photos, presumably including a half of a moon in the frame, must have been taken early while the telescope was still degassing and not yet near it's final not-in-focus best focus. It may be some several times worse than the final focus.

Posted by: djellison Jan 17 2006, 09:55 AM

I'm still waiting for the later calib images to come down

I have all the impactor imagery though

Doug

Posted by: djellison Jan 17 2006, 10:50 AM

Jupiter - this is two images, a longer (with moons visible but Jupiter bleached out) and a shorter (moons not visible, but Jupiter in good shape) exposure combined, poor focus can be seen on the Jovain Moons. This was 2005-02-06T03:43:57.303 ish...

Using the JPL solar system sim - they are, from top to bottom, Europe, Io and Ganymede ( http://space.jpl.nasa.gov/cgi-bin/wspace?tbody=599&vbody=399&month=2&day=6&year=2005&hour=03&minute=45&fovmul=1&rfov=0.1&bfov=30 ) - Callisto is out of shot below.

Unfortunately, just taken in 'clear' filter, so no colour - I'm trying to see if any of the calib obs were done in colour - the single star ones are fairly pointless, but the cluster and planetary obs should be fun.

Doug

Posted by: djellison Jan 17 2006, 11:00 AM

Nothing to see 'in' this one, but it's an RGB comp during some ""ENCOUNTER VALIDATION TEST" imaging, stretched to show the 4 areas of the CCD and how different they are w.r.t. noise. I'm not sure if the final 'nested' imaging (i.e. sub-framing) during the impactor event was using just one quadrant of this, or the middle of the 4 areas.

The High and Medium res on the flyby and Medium res on the Impactor ( i.e. all 3 visible cameras) share identical patterns, so one presumes it's a noise / electronics issue that is common to all, and thus (whilst I've not actually read that this is true) they must all share the same CCD design, much like MER does, across multiple instruments.

I'm going to try...TRY..and have a look at some IR info (I'll probably start with lunar calib data) , but it may be both mine and Emily's worst nightmare - an ISIS only situation.

Doug

Posted by: ugordan Jan 17 2006, 11:35 AM

Those are raw, uncalibrated images, right?
I seem to recall hearing that the reason the four quadrants are apparent is due to the pixels from the CCD being readout by four slightly different A/D converters. I think it was Emily who mentioned it in her DI blog, supposedly she asked one of the mission guys about this very issue.

The calibrated images of course shouldn't be prone to this behaviour.

Posted by: djellison Jan 17 2006, 11:36 AM

And umm..yeah...IR spectra.. Err..umm. yeah.

These are what you get when you open the .fit with Fits liberator.

Nice

Doug

Posted by: djellison Jan 17 2006, 11:37 AM

Yeah - this is uncalibrated cruise stuff - the encounter imagery is calibrated, so I'm guessing it wont have it

Doug

Posted by: ugordan Jan 17 2006, 11:42 AM

What I'd like to know is what the deal is with the first line in the samples, it seems to be corrupted or the likes? I also noticed this in the impactors frames, no matter how small the window was.
It's as though a "bar code" looking information was being overlaid on top of the frames.

Posted by: djellison Jan 17 2006, 11:44 AM

nIR-G-B of the moon, again, uncalibrated so it's cheated-levels to get it something like ordinary.

I think the first line ( first few lines actually ) are a sort of barcode.

Doug

Posted by: Phil Stooke Jan 17 2006, 05:26 PM

Yon 'barcode' is probably just what happens when a text header is attached to a binary file. Try opening the raw file in Word and see what happens!

Phil

Posted by: djellison Jan 17 2006, 06:10 PM

No really, NASA View, FITS Liberator and even the little JPG's that were on the raw DI webpage 6 months ago all have the same thing.

Doug

Posted by: Phil Stooke Feb 20 2006, 04:28 AM

Returning to this thread... Doug, are there other moon images in the calibration set? The team did release a very distant crescent view early in the mission, but are there any other views like those you posted here?

Phil

Posted by: djellison Feb 20 2006, 08:36 AM

Quite a few - I'm a bit flat out at the moment, but I'll have a poke around at lunch time at work

Doug