tag:blogger.com,1999:blog-6141980.post8178881743555877532..comments2024-03-20T12:28:35.004-05:00Comments on Nuit Blanche: Imaging with NatureIgorhttp://www.blogger.com/profile/17474880327699002140noreply@blogger.comBlogger3125tag:blogger.com,1999:blog-6141980.post-58006165584328660832009-08-28T12:30:48.266-05:002009-08-28T12:30:48.266-05:00Laurent,
For instance, you can take a look at ear...Laurent,<br /><br />For instance, you can take a look at earthshine studies on the Moon.<br /><br />http://www.obs-hp.fr/~larnold/publi_to_download/Arnold_2008_SpaceScieRev.pdf<br /><br />There the Moon acts as a mirror. Can we do better for the "Moon psf" given that we have probes over there ?<br /><br />Igor.Igorhttps://www.blogger.com/profile/17474880327699002140noreply@blogger.comtag:blogger.com,1999:blog-6141980.post-7079805375761330412009-08-28T11:09:42.411-05:002009-08-28T11:09:42.411-05:00Hello Laurent,
Yes, the cloud psf needs to be det...Hello Laurent,<br /><br />Yes, the cloud psf needs to be determined exactly and therefore the "calibration" needs to happen very fast.<br /><br />In a lidar mode, each measurement goes at the speed of light so I would assume it goes faster than most turbulence of interest in the cloud.<br /><br />There is a somewhat a related concept in astronomy:<br /><br />http://www.iop.org/EJ/article/0004-637X/651/1/544/20121.web.pdf?request-id=4316d87c-f3fe-4ffa-9c0f-6d2c44e3bdf8 <br /><br />and more , I'll write on this later.<br /><br />Cheers,<br /><br />Igor.Igorhttps://www.blogger.com/profile/17474880327699002140noreply@blogger.comtag:blogger.com,1999:blog-6141980.post-76695876726431746612009-08-28T02:13:34.926-05:002009-08-28T02:13:34.926-05:00I imagine that, if possible, it would be much easi...I imagine that, if possible, it would be much easier to realize such a PSF estimation with the different layers of the atmosphere (ionosphere) than with clouds. <br />The reason is that I guess some models of these layers (e.g. their interfaces reflectivity/refractivity) may be assumed sufficiently static, inducing a static PSF (wrt time) in certain EM sensing process.<br /><br />The fact is that if you use something like "in situ" measurements from some physical medium you do not control, you need a lot of calibration (see e.g. the "random lens imaging" MIT by Fergus and Torralba).<br /><br />Remember that in CS for instance, even if the matrix is randomly generated, you need to reproduce it latter (e.g. by storing it). <br /><br />In your framework, if the calibration the "cloud" PSF is slower than the evolution of the cloud configuration, it could be really difficult "deconvolve" the result. This is therefore an interesting problem ;-) <br /><br />Perhaps some basis facts already exist in the literature, as for using multiple telescopes to reduce atmospheric noise.<br /><br />My three cents.JackDhttps://www.blogger.com/profile/14728376685283207988noreply@blogger.com