{"id":99,"date":"2017-07-30T22:38:27","date_gmt":"2017-07-30T22:38:27","guid":{"rendered":"http:\/\/bcmeteors.net\/wp\/?page_id=99"},"modified":"2017-07-30T23:18:47","modified_gmt":"2017-07-30T23:18:47","slug":"sentinel-camera-calibration","status":"publish","type":"page","link":"https:\/\/bcmeteors.net\/?page_id=99","title":{"rendered":"Sentinel Camera Calibration"},"content":{"rendered":"

In December of 2008, after a series of back of the envelope type discussions on how to calibrate a Sentinel camera, Ken formalized the discussions in a pdf. To see Ken’s method\u00a0Click here for Ken’s original paper<\/a>\u00a0<\/a>on how we can calibrate the Sentinel camera.<\/p>\n

As a footnote I (Jeff) did a work through with my camera system. After the spreadsheet was made and a small Python program run Ken took my results and plotted it to see how his model stood up. Here are those results.<\/p>\n

Hi Jeff,<\/p>\n

I could not resist having a quick look. Your data is lovely. I simply plotted<\/p>\n

R = sqrt((x-x0<\/sub>)2<\/sup>+(y-y0<\/sub>)2<\/sup>)<\/p>\n

against zenith angle.<\/p>\n

In the first plot I assumed the camera zenith was (371,240), and in the second I optimized it, and got (370,231). This of course would be the camera zenith not the centre of the frame.<\/p>\n

HOWEVER: Look at the nice clean plot and good correlation. I think you can use the camera zenith method and ignore trying to find the centre of the frame; they are obviously very close because the plot, including the very slight nonlinearity due to the fisheye effect, integrates so cleanly.<\/p>\n

The very slight fisheye effect can be approximated more than adequately by a 2nd-order polynomial, as Martin Connors said it would.<\/p>\n

I would say, for your system, you should be able to simply calculate R and use the equation to get the zenith angle, and then do a rotation to find the azimuth error…. job done.<\/p>\n

Regards,<\/p>\n

Ken<\/p>\n

\"Brower's<\/p>\n

 <\/p>\n

 <\/p>\n","protected":false},"excerpt":{"rendered":"

In December of 2008, after a series of back of the envelope type discussions on how to calibrate a Sentinel camera, Ken formalized the discussions in a pdf. To see Ken’s method\u00a0Click here for Ken’s original paper\u00a0on how we can calibrate the Sentinel camera. As a footnote I (Jeff) did a work through with my … Continue reading “Sentinel Camera Calibration”<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-99","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/bcmeteors.net\/index.php?rest_route=\/wp\/v2\/pages\/99","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/bcmeteors.net\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/bcmeteors.net\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/bcmeteors.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/bcmeteors.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=99"}],"version-history":[{"count":1,"href":"https:\/\/bcmeteors.net\/index.php?rest_route=\/wp\/v2\/pages\/99\/revisions"}],"predecessor-version":[{"id":100,"href":"https:\/\/bcmeteors.net\/index.php?rest_route=\/wp\/v2\/pages\/99\/revisions\/100"}],"wp:attachment":[{"href":"https:\/\/bcmeteors.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=99"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}