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Hubble Space Telescope
No Shift, 180 Degree Rotation

1: Introduction

In this series of tests, we tested the performance of WFC3/UVIS instrument distortion coefficient table (IDCTAB) uab1537bi_idc.fits. This IDCTAB contains uniquely computed distortion solutions for 10 filters: F225W, F275W, F336W, F390W, F43W, F555W, F606W, F775W, F814W, and F850LP. All other filters use the values for F606W.

This series of tests is designed to test how the IDCTAB deals with a large (180°) rotation. To that end, two sets of observations were required for this test. The first set was taken in mid-july 2009, and the second set was taken in mid-January 2010 and is rotated by 180° from the first set.

Unfortunately, observations of only 6 of the 10 filters with unique IDCTAB solutions were obtained. Observations were available for filters F225W, F275W, F336W, F438W, F606W, and F814W. Observations were unavailable for filters F390W, F555W, F7775W, and F850LP. Additional details of the observations used for this test can be found in the summary table below.

Summary of Relevant Observation Information
RootnameProposal IDTarget NameFilterExposure TimeDate of ObservationOrientatX PostargY PostargRA PostargDEC Postarg
iaby02x5q 11452 OMEGACEN F225W 350.000000 2009-07-15 -28.40584775040186 0.000000 0.000000 2.016968333333E+02 -4.747956944444E+01
ibc301r3q 11911 OMEGACEN F225W 900.000000 2010-01-14 149.7683471644897 0.000000 0.000000 2.016928333333E+02 -4.747905555556E+01
iaby02x0q 11452 OMEGACEN F275W 350.000000 2009-07-15 -28.40584775040186 0.000000 0.000000 2.016968333333E+02 -4.747956944444E+01
ibc301qtq 11911 OMEGACEN F275W 800.000000 2010-01-14 149.7683471644897 0.000000 0.000000 2.016928333333E+02 -4.747905555556E+01
iaby02x4q 11452 OMEGACEN F336W 350.000000 2009-07-15 -28.40584775040186 0.000000 0.000000 2.016968333333E+02 -4.747956944444E+01
ibc301r5s 11911 OMEGACEN F336W 350.000000 2010-01-14 149.7683471644897 0.000000 0.000000 2.016928333333E+02 -4.747905555556E+01
iaby02wzq 11452 OMEGACEN F438W 35.000000 2009-07-15 -28.40584775040186 0.000000 0.000000 2.016968333333E+02 -4.747956944444E+01
ibc301qxq 11911 OMEGACEN F438W 350.000000 2010-01-14 149.7683471644897 0.000000 0.000000 2.016928333333E+02 -4.747905555556E+01
iaby02x7q 11452 OMEGACEN F606W 35.000000 2009-07-15 -28.40584775040186 0.000000 0.000000 2.016968333333E+02 -4.747956944444E+01
ibc301qrq 11911 OMEGACEN F606W 40.000000 2010-01-14 149.7683471644897 0.000000 0.000000 2.016928333333E+02 -4.747905555556E+01
iaby02x2q 11452 OMEGACEN F814W 35.000000 2009-07-15 -28.40584775040186 0.000000 0.000000 2.016968333333E+02 -4.747956944444E+01
ibc301qzq 11911 OMEGACEN F814W 40.000000 2010-01-14 149.7683471644897 0.000000 0.000000 2.016928333333E+02 -4.747905555556E+01

2: Iteration I

Iteration 1 Statistics Computed From Binned Vector Plots
FilterX RMSY RMSVec Mag RMSVec Mag MeanVec Mag MedianVec Mag MaxVec Mag Min
F225W 0.0273771 0.0464570 0.0259423 73.6910 73.6885 73.7656 73.6290
F275W 0.0214518 0.0164090 0.0219909 73.3759 73.3756 73.4472 73.3180
F336W 0.0192472 0.0236598 0.0188642 73.4310 73.4309 73.4816 73.3862
F438W 0.0260414 0.0192975 0.0235492 72.1972 72.1935 72.2718 72.1456
F606W 0.0228731 0.0226034 0.0230881 73.0718 73.0683 73.1339 73.0144
F814W 0.0184914 0.0234663 0.0192754 72.1775 72.1787 72.2330 72.1179

F225W

F275W

F336W

F438W

F606W

F814W

Shift.dat parameters by Filter
FilterX ShiftY ShiftRotationScale
F225W 62.94205 38.32008 -0.000429999999994 0.999988
F275W 62.95741 37.68903 0.00022 0.9999965
F336W 63.59559 36.71012 -0.000310000000013 0.9999953
F438W 62.4213 36.27583 -2.99999999811e-05 0.9999984
F606W 62.73308 37.4697 -0.000209999999981 1.0
F814W 62.32654 36.39898 -2.99999999811e-05 0.9999982

NOTE: In the above table, shift values are in units of drizzled image pixels, rotation values are in units of degrees, and scale values are dimensionless multipliers.

3: Iteration II

Iteration II Statistics Computed From Binned Vector Plots
FilterX RMSY RMSVec Mag RMSVec Mag MeanVec Mag MedianVec Mag MaxVec Mag Min
F225W 0.0336515 0.0331442 0.0203942 0.0427191 0.0400018 0.160794 0.00249708
F275W 0.0191096 0.0171655 0.0123848 0.0226815 0.0198300 0.0587857 0.00205341
F336W 0.0214420 0.0185267 0.0134341 0.0250760 0.0234981 0.0866359 0.00100080
F438W 0.0253918 0.0193347 0.0151199 0.0283531 0.0268018 0.0928217 0.00325246
F606W 0.0245699 0.0206247 0.0158022 0.0279968 0.0268345 0.120874 0.000937763
F814W 0.0184651 0.0236663 0.0154733 0.0259433 0.0235946 0.0751794 0.00179471

F225W

F275W

F336W

F438W

F606W

F814W

4: Summary

Shift

Rotation

Scale

Fit RMS

Number of Matched Stars