GB17/00, flight day 164/2017, Alconbury

[dac]

Data location: ~arsf/arsf_data/2017/flight_data/nerc-arf_internal/GB17_00-2017_164_Alconbury

Data arrived from NERC-ARF via network transfer (uploaded to RSG FTP) 2017-06-14

Scientific objective: Internal boresight flight

Priority: Urgent

PI: NERC-ARF

Sensors:

• Fenix (requested/not requested, flown/not flown)
• Leica LIDAR (requested/not requested, flown/not flown)
• OWL (requested/not requested, flown/not flown)
• PhaseOne (requested/not requested, flown/not flown)

[dac]

Data unpacked and standard checks run. No log file present for Fenix line 2. James mentioned IPAS data is a different format - single file compared to multiple. Need to check if this is a problem.

[dac]

Navigation processing

The NERC-ARF basestation and OS RINEX St Neots (SNEO) were both used for flight. Downloaded RINEX data and used ephemeris data from basestation. Need to get basestation height before this can be used for processing so proceeding using only OS RINEX data for now

Basestation PPP result for SNEO

lat	52 11 07.33081
long	-0 06 44.97057
height	120.195

[lah]

Owl checks

Ran through the Owl preprocessing checks (on wiki page) and everything looks ok so far.

As the Owl can be calibrated without waiting for the navigation or the fenix calibration to be finished I sent these jobs to the grid. Unfortunately these failed, so I will fix the script now. I saw a similar error working with the laptop batch processing script, so think something has changed in the way flags are being passed with subprocess and they now can't handle 2 inputs to the same flag in the same line (-l for memory and apl throttle) .

[lah]

Owl

Committed code fix to ​https://gitlab.rsg.pml.ac.uk/arsf/internal-code/merge_requests/171. Is now running fine on grid.

[dac]

Navigation Processing

IPAS Honeywell: Used location from file. Interpolated to match IPAS data. Default elevation mask of 10 degrees.

[lah]

Owl

Level 1b files look fine. There is an interesting building(?) towards the end of line 5 and the start of line 1 which is showing a lot of spectral features - first time I've seen anything this distinct. Would be good to find out the material.

[asm]

Lidar

Have tested processing lidar files using alspp.exe and the old calibration files. All worked trough with clear pitch and roll errors but they do not look very bad. Clouds are showing below the ground however.

[lah]

Replying to dac:

Data unpacked and standard checks run. No log file present for Fenix line 2. James mentioned IPAS data is a different format - single file compared to multiple. Need to check if this is a problem.

Should probably change the sensor ID as part of unpacking for the rest of the season.

[dac]

Hyperspectral Processing

Ran through processing using lever arms from 2015 (only Twin Otter survey) and calibration Specim provided.

Compared radiance spectra to 6S simulations using check_fenix_spectra_py6s.py and found a good match - no obvious problems.

Timing fix looks like it worked for lines 1 and 5 but not 2, 3 and 4 so will need to investigate further and possibly manually determine SCT values before boresight processing.

[dac]

PhaseOne Processing

Processed the images using iX Capture without any problems. Colours don't look quite right so will need to check on the settings.

[asm]

Hyperspectral Processing

asm has taken over this project. Found SCT values:

Flightline	FENIX
1	1.02
2	1.96
3	2.07
4	1.99
5	1.08

[dac]

Navigation Processing

Processed IPAS20 data. This will now be used for Fenix processing.

[asm]

Hyperspectral Processing

Lidar is not operative so restarting fenix boresight using Ipas20 sol file instead

[asm]

Navigation processing

Done the NERC-ARF basestation verification. Got height from file.

lat	52 05 44.19041
lon	0 08 15.45307
El. Height	79.234 m
Ant Height	0.085 m, to L1-PC, LEIAX1202GG

[asm]

Navigation processing

Litton IMU boresight angles needed to be set to 0, 0, 0 instead of default 0, -90, 90 (working for ipas_honeywell). That solved problems with the navigation (sol was providing a steady roll flight of -90 degrees).

[asm]

Hyperspectral Processing

Found boresight for Fenix: 0.37 -0.51 -0.35 (pitch, roll and heading).

[dac]

Hyperspectral Processing

Checked boresight values against OS Open Vectors and survey data and look good.

[lah]

Owl

Started mapping files. A few problems with the config file were resolved manually:

• Had to specify sol file as multiple present
• Added boresight from previous
• Copied owl_fov_fullccd_vectors.bil into arsf 2017 calibration folder
• Set pixel size (defaults to 0 and causes a confusing error "Cannot create an area whose minimum x/y is greater than or equal to its maximum x/y.-0 0 0 0")

[lah]

Scts for Owl

Flightline	OWL
1	2.01
2	1.99
3	2.01
4	1.99
5	1.97

[lah]

Owl Boresight

Very difficult to calculate heading offset as the only pair of overlapping flightlines in the same direction have very little overlap and the data are largely offset. Also different altitudes of the opposite direction pair make roll and pitch more difficult to identify. Going to try a bit more trial and error with the other 2 lines to see if the boresight values (0.15 0.08 0.30) can be improved.

[lah]

Owl Boresight

Gone through a fair few changes and think that the best that can be achieved with the data is:

pitch: 0.08 roll: 0.20 heading: 0.30

Will check this looks ok for the summer school when processing.

[dac]

Fenix processing

Set correct sensor ID in raw files using:

sed -i "s/sensorid = 350005/sensorid = 350006/g" *hdr
sed -i "s/sensorid = 350005/sensorid = 350006/g" *hdr

[dac]

Fenix Boresight

Found new boresight pitch values with correct FOV file for load instrument. Values are now:

0.45 -0.51 -0.35 (pitch, roll and heading).

[asm]

Digital Camera

A partial delivery previously created for testing was deleted and a new delivery was created with the new scripts. Awaiting for delivery check.

[dac]

Digital Camera

Delivery looked fine. Corrected PI from 'ARSF' to 'NERC-ARF' in readme and finalised.