MEX VMC - Back on, and online! Options

[djellison]

I heard about this 24 hours ago, and couldn't believe it - this is EXACTLY what has been missing from ESA. MASSIVE kudos to the ESOC MEX flight ops team for doing it

http://www.esa.int/SPECIALS/VMC/index.html

The last time I wrote a post and hit 'submit' at UMSF with a smile this big on my face, was when Oppy successfully got out of Purgatory.

[ormstont]

All really nice work! Where to start?!

Colour enhancement
Really cool enhancements of the colour of the images, we've been thinking for a while of boosting the colour to get more like the Mars people are used to seeing. If you get something you're happy with showing off it'd be great to post it to the blog and hopefully introduce it into our workflow so all images would be enhanced before upload.

Lens Artefacts
I'd love not to have the artefacts on the image and in fact I don't think we had them at launch (check out the pre-separation Beagle images). My theory is that debris from the ejection of Beagle (VMC sits right underneath the Beagle separation mechanism) might have hit the lens but I'm not sure it would produce the artefacts seen - anyone that can "reverse engineer" what sort of thing would cause them might make for an interesting blog article.

Flat-fielding
First off, I think the initial flat-field test by ugordan already seems to be a huge improvement on what we've got at the moment! I'm not sure if there are any images in the library that would at least get us closer to the data we need, perhaps some of the early exposure tests and crescent images or previous low altitude observations. Generally though we could consider doing a flat-field observation, although the chances to do low-altitude images are very rare so would be good to use them for proper imaging. What sort of image would we be looking for? Good exposure, under/over-exposure? Planet filling the image, only part of the image? etc. etc.

Exposure Settings
The exposure settings we use at the moment (the loop of 4) is as you guessed meant to be a good approximation to catch any lighting conditions regardless of phase angle. The middle two exposures are usually the best but I put the darker one in for extremely bright conditions and the brighter one for dim features like faint clouds. There have actually been two loops of 4 used: 0.4, 6.8, 14, 22.8 and the tightened range (currently in use): 2.8, 6, 10, 14 (all times in milliseconds). We actually have available a range from 0.4 to 191.6 milliseconds in steps of 0.8 milliseconds. If anyone can demonstrate from past images that tighter settings or even a loop of 2 or 3 exposure settings would still give good results then please let us know and we can change it! We have the ability to set the exposure individually for each image.

Image frequency
We've actually slightly improved the image frequency recently and are now really at the maximum frequency that VMC can support. This means an image every 44 seconds which is a hard constraint caused by the amount of time it takes the rather basic VMC to write the captured image to the on-board storage of the spacecraft.

Hopefully this answers some of the questions cropping up, of course please do send us by e-mail any results, processing or analysis done on the image for us to post on the blog. djellison sent us those wonderful movies he created and hopefully they'll be going up soon! Thanks again for your interest in VMC!