Journey to Mt Sharp - Part 4: Beyond the Kimberley, Sol 634 [May 19, '14] to 706 [Jul 31, '14] Options

[PaulH51]

I'm a little surprised that no one has commented on the MARDI drive video yet.

Fingers crossed we don't have to wait long for the full frames

[mhoward]

I'm a little surprised that no one has commented on the MARDI drive video yet.
http://mars.jpl.nasa.gov/msl/multimedia/ra...mp;camera=MARDI

Some people probably didn't see it because it isn't on Midnight Planets, because the filenames for that sequence don't conform to the format defined in the MMM Software Interface Specification (MSL_MMM_EDR_RDR_DPSIS.PDF). They're three characters too long; looks like number overflow again.

[anticitizen2]

Some people probably didn't see it because it isn't on Midnight Planets, because the filenames for that sequence don't conform to the format defined in the MMM Software Interface Specification (MSL_MMM_EDR_RDR_DPSIS.PDF). They're three characters too long; looks like number overflow again.

Yeah, thats how I missed them! (Midnight Planets is an incredible tool for compulsive rover-following, so thank you)


EDIT: more frames


So, who wants to stitch them into a panorama?

[mcaplinger]

The exposure time was set by autoexposure when the camera was looking into shadow, and then the drive put us in a much brighter illumination geometry. Next time we'll probably use a pre-calculated manual exposure.

[Astro0]

Quick playaround with the MARDI images to improve the view.
Gamma stretched, strained the colour etc...

http://youtu.be/Kd81xvgYx30

It will be nice to see the larger files if they come down.
Certainly the next time will be better with lessons learned as Mike pointed out

[algorithm]

Having looked at the great animations above I thought I would have a go myself.
To that end I put together some ChemCam images from sol654, they show ripples propogating from the centre of the target. I assume that's dust being moved by heat, or vibration.

[fredk]

Nice. I guess each frame follows another blast from the laser.

[algorithm]

Nice. I guess each frame follows another blast from the laser.

Would things be happening too fast for the effects to be captured from a single blast? Could frames be captured that fast - as in a high speed camera?

[fredk]

These frames were taken over a span of several minutes. I didn't think chemcam had video capability.

[algorithm]

These frames were taken over a span of several minutes. I didn't think chemcam had video capability.

Agreed, the frames are apparently as you say, each of the effects of several successive blasts.

ChemCam as a video camera isn't what I had in mind, more along the lines of a high speed digital slr, I don't know how many frames a second would be needed to capture some kind of 'motion' resulting from a laser shot though.

Probably nothing like what the camera was designed for....maybe next time.

My greyscale images would be great in colour, if anyone could give me some tips on that they would be most welcome.

[djellison]

When it's firing the laser, the spectrometer of ChemCam is collecting data for the spectra - not sure if it could image at the same time. I would expect it's a few seconds between frames in any case.

D

[fredk]

There was a sequence of images on 283 that suggest simultaneous laser firing and imaging:

[mhoward]

There was a sequence of images on 283 that suggest simultaneous laser firing and imaging:

At the time, I remember being corrected on that: the light in the image isn't the laser. I can't recall what it actually was; a more conventional light used for targeting, or something like that.

[elakdawalla]

Sadly, that's not the ChemCam laser, at least not in the way you're thinking. Mike Howard tweeted about that image back when it was taken, and Ryan Anderson replied "This isn't ChemCam laser firing. It's alignment laser. Vertical line not laser, just overexposure." I'm not actually sure I understand the distinction myself. I haven't written the book section on ChemCam yet.

Edit: Mike: jinx!

[fredk]

Definitely the vertical streak extending below the bright spot is not a laser beam, since the beam would be coaxial with the optical axis. It doesn't really look like CCD bleeding, but must be some related effect.

According to the chemcam description paper there are two lasers - LIBS is the main laser, and there's also a lower power continuous wave (CW) laser used for autofocus. Both beams are coaxial with the optics. That paper states that "the [LIBS] spark itself cannot be observed". But apparently the autofocus spot can be. Fig 64 in the paper shows that the CW beam spot has a size, shape, and orientation matching well the spot in the image I linked to above. So it looks like they imaged the autofocus laser spot, perhaps to check the alignment.