Boresight calibration metaticket

[mggr]

This ticket is to describe the task of acquiring the 2007 boresight calibration.

There are two periods:

• start of year -> day 130 (ATM, Eagle, Hawk)
• (solas dust campaign, using atmospheric instruments)
• day 166 -> end of year (ATM, CASI, Eagle, Hawk)

This ticket has been created after the fact, so the dates are going to be wrong.

See also: Processing/BoresightCalibration

[mggr]

Begun boresight calib at end of July with day 166 calibration flight. Many problems attempting to get highly accurate results for Eagle and Hawk. Eventually accepted tolerable results (~5m accuracy) at the end of August.

A key problem, discovered late on, was that Eagle and Hawk lines for 2007 have small timing errors that must be manually corrected for each line. This throws off the accuracy of any boresighting.

Also, Bill has told us not to trust the edges (where edges = several degrees) of the swaths, particularly in the Specim instruments.

[mggr]

In Oct, Anthony has looked at the 166 boresight again, made timing corrections and has confirmed the Eagle & Hawk numbers. He's also produced ATM and CASI numbers (again with some uncorrectable inaccuracy).

ATM: 0.0 -2.22 -0.75

Eagle: 0.23 -0.28 -1.4

Hawk: 0.0 0.35 -1.4

CASI: -0.85 -0.08 -0.4

This completes the >166 boresight process.

[mggr]

Anthony has worked on the < day 130 calibration in the last week or so. He has been using the day 130 calibration flight. The other option would be the 061 flight, which is marked "don't use".

ATM seems to have some timing problems and strangely doesn't line up consistently - going to investigate this more deeply.

Hawk is ok but only two of the four lines are processable. The other two don't have specim sync and we can't correct for this until Bill gives us an updated azspec (see #73).

Eagle has no .nav files. We were able to use the Hawk .nav files, but could only process two lines then. When processed, these two lines came out totally blank(!).

[mggr]

Used vector overlays to try and correct the yaw on the Hawk flights for 130 (as we don't have crossing flight lines).

Anthony has tried processing the 061 ("don't use") boresight flight. Many of the lines do not process (need to get him to add the reasons here). Of the few that do, they do not cover the boresight area. Guess that's why we shouldn't use this dataset ;)

I've asked Anthony to try and get an approximate boresight from one of the Loch Leven flights (103a, #49) as that has good quality Eagle data and a number of roads and buildings present. There are no crossing flights, so we'll have to rely on vector overlays again :(

[mggr]

Boresight numbers for days 061 - 130, based on eyeballing 103a and some vector layers:

ATM: 0.08 -2.3 -0.75

Eagle: -0.25 -0.5 -1.2

Hawk: -0.3 0.1 -1.4

The Hawk numbers don't line up particularly well with the ones Anthony got from 130, but 130 was pretty trashed, so it's hard to tell if this is a problem. He's said that his new numbers appear to work ok for day 116.

[mggr]

Final boresight (254b) arrived from ARSF (~arsf/arsf_data/in_progress/2007/flight_data/boresight/boresight-2007_254b/). This is the counterpart to 166 - might be worth a quick test to verify our 166 numbers are good.

Passing this ticket to anee to do the test at some point (low priority).

Sigh, CASI data is missing - will sync over the network and update ticket when it's here.