Voyager camera pointing information Options

[Brian Burns]

Sorry if this has been discussed anywhere but I can't seem to find much information about it - why is it that Voyager's pointing is so haphazard, as in this video of all the RAW Jupiter images - https://www.youtube.com/watch?v=bf5QJ8iFxUs?

I came across this link which says that pointing information for the images exists - http://pds-rings.seti.org/voyager/ck.html, but have also read on this forum that it's not very accurate. Would the information be useful in automatically aligning composite images and mosaics, or is it too coarse? Would it at least be useful in getting general alignments that could be refined by hand?

And does anyone know why the cameras could not be pointed more accurately, or why accurate information could not be returned with the images? I assume it was some technical limitation, but just curious what it might be.

[JohnVV]

i use gmic ( was called GREYCstoration ) but it evolved into including basically everything Imagemagic can do and the PDE based smoothing and inpainting

the pds imq ( yes the IMQ ) header has a x/y points for the reseau marks

CODE

  Group = Reseaus
    Line     = (12.6, 7.0, 4.0, -1.2, -4.6, -6.3, -8.0, -8.6, -8.9, -8.2,
                -10.0, -3.2, 22.9, 26.0, 22.0, 18.0, 17.0, 15.0, 14.0, 13.0,
                13.0, 14.0, 8.0, 58.0, 55.1, 51.0, 48.0, 46.0, 44.0, 43.0,
                42.0, 41.0, 41.0, 43.0, 44.0, 94.0, 90.0, 88.0, 85.0, 84.0,
                82.0, 81.0, 81.0, 80.0, 81.0, 81.0, 131.9, 130.0, 118.7, 120.0,
                169.9, 167.1, 164.8, 164.0, 161.8, 160.7, 159.9, 160.0, 158.5,
                159.0, 159.0, 208.5, 208.0, 197.6, 197.6, 247.6, 245.5, 243.8,
                242.6, 241.6, 240.6, 239.9, 239.2, 238.4, 237.7, 237.3, 286.8,
                286.0, 277.2, 276.7, 326.4, 324.7, 323.3, 322.3, 321.5, 320.6,
                320.0, 319.3, 318.5, 317.5, 316.9, 366.0, 365.2, 357.0, 356.5,
                405.6, 404.2, 403.0, 402.1, 401.3, 400.6, 399.9, 399.1, 398.3,
                397.4, 396.4, 445.2, 444.6, 436.4, 435.6, 485.0, 483.7, 482.8,
                481.9, 481.1, 480.4, 479.6, 478.9, 478.0, 476.8, 475.5, 524.4,
                524.2, 515.6, 514.6, 564.4, 563.3, 562.4, 561.6, 560.8, 560.0,
                559.3, 558.4, 557.4, 556.0, 554.3, 603.5, 603.5, 593.0, 592.6,
                643.1, 642.5, 641.0, 641.0, 640.2, 638.0, 637.0, 636.0, 635.0,
                634.4, 630.0, 682.0, 682.0, 671.0, 669.3, 720.6, 720.9, 720.0,
                719.0, 718.0, 717.0, 716.0, 714.0, 712.0, 710.0, 706.0, 757.7,
                759.1, 758.0, 758.0, 757.0, 756.0, 755.0, 753.0, 752.0, 750.0,
                746.0, 743.4, 795.4, 787.0, 787.0, 786.0, 785.0, 784.0, 783.0,
                782.0, 780.0, 776.0, 778.0, 804.0, 810.7, 808.5, 808.5, 808.0,
                807.4, 806.1, 805.0, 801.0, 798.0, 798.5, 787.0, 120.0)
    Sample   = (0.4, 44.0, 119.0, 199.9, 278.0, 356.1, 433.9, 511.6, 588.5,
                664.1, 737.1, 784.4, 6.0, 81.0, 158.0, 236.0, 314.0, 393.0,
                471.0, 549.9, 626.3, 702.0, 772.0, -5.8, 43.0, 120.0, 199.0,
                276.0, 355.0, 433.0, 512.0, 589.0, 666.0, 740.0, 792.0, 15.0,
                81.0, 159.0, 238.0, 317.0, 395.0, 474.0, 551.0, 629.0, 705.0,
                769.0, -4.6, 43.0, 744.1, 793.0, 15.3, 82.3, 159.0, 238.0,
                318.1, 396.7, 475.2, 553.3, 631.0, 707.7, 773.5, -5.3, 43.0,
                746.8, 795.7, 15.3, 82.4, 160.8, 239.0, 318.0, 397.4, 475.9,
                554.3, 632.3, 709.6, 775.7, -5.1, 43.9, 748.7, 797.8, 15.6,
                82.9, 161.3, 240.1, 319.0, 397.8, 476.4, 555.0, 633.2, 710.9,
                777.5, -4.6, 44.4, 749.8, 799.3, 16.4, 83.4, 161.7, 240.4,
                319.3, 398.1, 476.9, 555.5, 633.8, 711.7, 778.5, -3.8, 45.3,
                750.4, 801.8, 17.5, 84.4, 162.3, 240.9, 319.7, 398.4, 477.2,
                555.9, 634.3, 712.3, 779.2, -2.3, 46.4, 751.0, 799.8, 19.0,
                85.4, 163.0, 241.4, 320.0, 398.9, 477.5, 556.4, 634.7, 712.7,
                779.4, -0.5, 48.0, 752.0, 800.0, 21.3, 86.9, 163.9, 242.0,
                320.6, 401.0, 479.0, 558.0, 636.0, 712.7, 778.0, 2.6, 50.4,
                752.0, 799.5, 26.0, 89.2, 166.0, 243.0, 322.0, 401.0, 480.0,
                559.0, 637.0, 714.0, 778.0, 4.5, 54.0, 129.0, 206.0, 284.0,
                362.0, 441.0, 519.0, 598.0, 675.0, 751.0, 800.0, 22.2, 93.0,
                168.0, 245.0, 323.0, 402.0, 481.0, 559.0, 637.0, 713.0, 785.0,
                11.0, 56.6, 129.6, 205.8, 283.3, 361.5, 439.8, 518.3, 599.0,
                675.6, 748.7, 794.0, 591.0)

this was for the voyager "c1133337.imq" ingested into isis3 , before any work on it

there is old c code for reading the imq's
http://pds-imaging.jpl.nasa.gov/data/vg2-n..._0009/software/
http://pds-imaging.jpl.nasa.gov/data/vg2-n...re/softinfo.txt

[Brian Burns]

Thanks, G'mic looks interesting, especially if it can do inpainting well.

I've got the program set up to use the later PDS volumes, so would be using that data - it includes the reseau mark locations like so -

C1469813_RESLOC.TXT:
This is a table of the center locations of
the reseau markings in the corresponding raw image, C1469813_RAW.IMG. The
table has 202 rows, one per reseau marking. Each row contains values for the
line and sample coordinates. Note that lines and samples range from 1 to 800,
although some reseau markings can fall outside these limits. This file was
derived from the corresponding VICAR-format binary data file
C1469813_RESLOC.DAT. It has been converted to ASCII text format for users'
convenience. An extra column contains the reseau marking number as originally
identified by the Voyager Imaging Team; this number differs from the order of
the rows in the file. See Fig. 1 of
Danielson, G. E., P. N. Kupferman, T. V. Johnson, and L. A. Soderblom 1981.
Radiometric performance of the Voyager cameras. J. Geophys. Res. 86, 8683-
8689.

C1469813_RESLOC.TAB:
1, 4.9486, 12.4470, 1
2, 0.3756, 51.5631, 3
3, 2.4425,126.7564, 4
4, 1.5738,205.6022, 5
5, -0.2871,282.6453, 6
6, -0.1777,362.7857, 7
...

For filling in large gaps, I was thinking that since the program knows what the size of the target should be (thanks to the SPICE data), once you have the image centered, you could fill in the target area where it's black by filling in from the previous good frame, and blurring the edges a bit. Either that or some kind of texture synthesis, e.g. http://eric-yuan.me/texture-synthesis/.

I'm still having trouble stabilizing images due to all the bad frames, so cleaning up the images might need to be higher in priority - until then the movies are going to be fairly choppy. But the expected target size from SPICE has matched the actual image very well from the images I've looked at, so that might help with centering the images, since the Hough circle detector can look for circles of a specific radius.