PHOTOGRAPHIC IMAGES OF THE NEAR-SUNSET TOTAL SOLAR ECLIPSE
04 DECEMBER 2002
LINDON STATION (FORTEVILLE BORE) SW AUSTRALIA
GLENN SCHNEIDER (gschneider@mac.com)



Click HERE for background information on the preliminary planning for this eclipse observation.


This is a PRELIMINARY photographic report.  Images of the Total Solar Eclipse of 04 December 2002 are presented in a format suitable for web (screen) based viewing.  Higher resolution images will be made avaialble at a later date. All images were taken on Fuji NPZ Color Negative Film pushed processed by 1 stop (to ISO 1600).  Two 35mm cameras were employed:

1) A "High Resolution" camera with a 1.2 meter focal length f/12 NIKON achromatic refractor objective lens (3.94" clear diameter), with two 1/8-wave fold-flats, assembed as a ridged "folded refractor".

2) A "Wide Field" camera with a 400mm f/5.6 refracting lens.

Both cameras were fixed to a common mount and operated by the UMBRAPHILE automated solar eclipse photography S/W, each under electro-mechanical control of a high-speed solenoid shutter actuator.  The camera set-up is shown below:


(Click for additional photographs of the OZCAM: 1, 2, 3)



The eclipse was observed from:

LINDON STATION - FORTVILLE BORE, SOUTH WEST AUSTRALIA
LATITUDE: -029° 07' 53.0''
LONGITUDE: +140° 53' 50.0''
ALTITUDE: 120 meters

With a

PREDICTED (see note on post-facto delta-T correction)
PENUMBRAL DURATION = 01:51:00.9
UMBRAL DURATION    = 00:00:26.6
MAXIMUM MAGNITUDE  = 1.004

and a

PREDICTED (see note post-facto delta-T correction)
Cnt hh:mm:ss.f Alt°  P.A°
1ST 08:14:38.0 +13.1 274.9
2ND 09:11:25.3 +01.5 086.4
MID 09:11:38.6 +01.5
3RD 09:11:51.8 +01.4 266.5
4TH 10:05:38.9 -08.9 093.2
With Lunar Limb Corrections Applied.



The photographic sequence executed for both cameras was as follows:

EXECUTED UMBRAPHILE 2.4.1A EXPOSURE SEQUENCE
## T-cont T-mid  T+CII UT of EXP DURAT 1/DUR
 1  -9.00 -22.29 -9.00 091116.26 0.100 10.00
 2  -8.00 -21.29 -8.00 091117.26 0.100 10.00
 3  -7.00 -20.29 -7.00 091118.26 0.100 10.00
 4  -6.00 -19.29 -6.00 091119.26 0.100 10.00
 5  -5.00 -18.29 -5.00 091120.26 0.100 10.00
 6  -4.00 -17.29 -4.00 091121.26 0.100 10.00
 7  -3.00 -16.29 -3.00 091122.26 0.100 10.00
 8  -2.00 -15.29 -2.00 091123.26 0.100 10.00
 9  -1.00 -14.29 -1.00 091124.26 0.100 10.00
10   0.00 -13.29  0.00 091125.26 0.050 20.00
11   2.05 -11.25  2.05 091127.31 0.088 11.35
12   4.09  -9.20  4.09 091129.35 0.155  6.44
13   6.14  -7.16  6.14 091131.40 0.274  3.65
14   8.18  -5.11  8.18 091133.44 0.483  2.07
15  10.23  -3.07 10.23 091135.49 0.851  1.18
16  12.27  -1.02 12.27 091137.53 1.500  0.67
17  12.27   1.02 14.32 091139.58 1.500  0.67
18  10.23   3.07 16.36 091141.62 0.851  1.18
19   8.18   5.11 18.41 091143.67 0.483  2.07
20   6.14   7.16 20.45 091145.71 0.274  3.65
21   4.09   9.20 22.50 091147.76 0.155  6.44
22   2.05  11.25 24.54 091149.80 0.088 11.35
23   0.00  13.29 26.59 091151.85 0.050 20.00
24  -1.00  14.29 27.59 091152.85 0.100 10.00
25  -2.00  15.29 28.59 091153.85 0.100 10.00
26  -3.00  16.29 29.59 091154.85 0.100 10.00
27  -4.00  17.29 30.59 091155.85 0.100 10.00
28  -5.00  18.29 31.59 091156.85 0.100 10.00
29  -6.00  19.29 32.59 091157.85 0.100 10.00
30  -7.00  20.29 33.59 091158.85 0.100 10.00
31  -8.00  21.29 34.59 091159.85 0.100 10.00
32  -9.00  22.29 35.59 091200.85 0.100 10.00

As defined by the Umbraphile Data File used:

Exposures 33-38 of sunset partial eclipse (unfiltered)
were triggered manually and exposed at 0.01s (1/100th second)



Note on Image Presentation

Images presented here are from low (512x768 pixel) resolution scans (1.13Mb per original file).
Negatives are currently being scanned to 2048x3072 and higher resolution digitized images will be available soon.
NO color correction, transformations or brightness/contrast adjustments have been made.

ALL images are JPEG compressed (but at "best" quality) for web display, and do
not reflect the quality of the original photographic negatives.



High Resolution (1200 mm) Images

CLICK HERE TO SEE THE PHOTO GALLERY FROM THE "HI-RES" CAMERA

If your browser does not support frames the individual images may be found in the Hi-Res Directory.

HI-RES images have been registered and cropped, partial phases rotated to compensate for camera tilt.

UMBRAPHILE 2002: THE MOVIE (QUICKTIME, 33.4Mbytes) in Real Elapsed Time



High Resolution (1200 mm) Images - Reprocessed

Using the above images I have done a bit of image processing to compensate for the facts that:

a) The exposure sequence was not temporally centered at mid-eclipse because of the 2.5s delta-T error (mea culpa)
b) The totality exposures had a cadence of 1 frame per 2.05s, while the diamond ring (DR) exposures were 1 frame per second
c) The planned CII and CIII exposures are shorter (by design) than the totality and DR images on either side of them
d) The star and end of the logarithmic ramps are very slightly shorter exposures then the DR exposures.

This sequence would have been optimal for my needs IF it were not offset from mid-eclipse.  What I did was:

a) Adjust apply multiplicative scaling constants to a few selected frames to achieve (approximately) logarithmically smooth transitions as the
background increased or decreased due to the change in the photospheric extent but asymmetrically w.r.t. the contacts and the planned ramps
b) applied a gamma correction to those frames to re-stretch the contrast appropriately for the adjusted dynamic range
c) augmented one frame which had excessive jitter by using the chromospheric and prominence data from it weighted and combined with radial gradient masking of the images on either side of it.

Then: For those frames with exposure start times spaced by 2 seconds, I created linerly-weighted (by signal-to-noise on a pixel by pixel basis) interpolated images, to "create" intermediate frames from their immediate neighbors.

It still is not perfect, I suspect because my solenoid control was probably not accurate in exposure time to better than 5-10% and some empirical adjustment may still be necessary.  However, for a first unbiased crack at processing I  am quite pleased with the results.  Here is a:

CONTACT SHEET OF THE HI-RES DATA WITH REPROCESSING AS DESCRIBED ABOVE

And here is UMBRAPHILE 2002: THE SEQUEL (QUICKTIME, 5.0 Mbytes) in Real Elapsed Time.  Yes, more frames but virtually the same size.  Beats me how QUICKTIME can do that - but it all was lossless w.r.t. the input resolution.   I think you will find it much improved over the original.  Indeed, I think you would be hard pressed to identify which were the interpolated frames - so I put an "I" after the timecode which identifies them by name.  Now, have fun moving the QuickTime slider after you see the movie.

Don't Miss This "Movie"!



Wide Field (400mm) Images

CLICK HERE TO SEE THE PHOTO GALLERY FROM THE "LO-RES" CAMERA

If your browser does not support frames the individual images may be found in the Wide Field Directory.

LO-RES images are raw scans from the CD.  Artifacts are from scan, not on negatives.



; UMBRAPHILE DATA FILE FOR 04 DECEMBER 2002 TOTAL SOLAR ECLIPSE
; FOR UMBRAPHILE 2.4.1B (OK for earlier versions, *MUST* use this file for 2.3.0+)
; For an explanation see: http://balder.prohosting.com/stouch/UMBRAPHILE.html
;
SOURCE   = 'USNOAA' ; Must be 'USNOAA' or 'NASARP'
DTYPE    = 'TRIG'   ; Must be 'TRIG' or 'DIRECT'
;
; PARAMETERS FOR COMPUTING BESSELIAN ELEMENTS - USNO STYLE
;
Range    =  -0.208, 5.350 ; Range in TDT for valid coefficients
T0       =   5 ; Base time for series expansion
DELTAT   =   0.0 ; Delta-T in seconds (0 if U.T. elements*)
XCOEF    =  -1.46281091,  0.55292625,  0.00009327, -0.00000870
YCOEF    =   0.03729996, -0.13193164,  0.00016091,  0.00000221
SINDCOEF =  -0.37801298, -0.00008614,  0.00000009,  0.00000000
COSDCOEF =   0.92580030, -0.00003518,  0.00000004,  0.00000000
MUCOEF   = 257.48810107, 14.99728461, -0.00000176, -0.00000002, -0.00417807
l1COEF   =   0.54382912,  0.00015788, -0.00001252,  0.00000001
l2COEF   =  -0.00254395,  0.00015709, -0.00001246,  0.00000001
tanf1    =   0.004747    ; Umbral Shadow
tanf2    =   0.004720    ; Penumbral Shadow
SD       = -22, 30, 31.0 ; Solar Declination at Mid-Eclipse
MUP      =   0.261752    ; Time derivative of MU in radians/hour
;
; Notes: (1) Delta-T = +67.0 seconds is "built-in" to these polynomial
; representations of the Besselian elements. For a different value
; of absolute Delta-T set DELTAT = Delta-T minus 67.0.
; (2) A correction of (+0.50", - 0.25") has been applied to the
; latitude and longitude of the moon to compensate for the
; displacement of the mean center of figure from the dynamical
; center of mass.
;
*POST-FACTO: Delta-T on 04 Dec 2002 = 64.47s
; *DELTAT = -2.47 should have been used
; *All predictions would move LATER in time by 2.53s
; *Exposure Sequence Executed with UT Times based on Delta-T = 67s
;
; ANCILLARY INFORMATION
; UT of Mid-Eclipse (geocentric conjunction) = 07h 38m 40.890s
;
; CAMERA CONTROLLER PARAMETERS
NUMEXP     = 32   ; Number of Exposures (*MUST* be even)
MAXEXP     = 1.5  ; Maximum Exposure Time (seconds)
MINEXP     = 0.05 ; Minimum Exposure Time (seconds)
MAXDCYC    = 100  ; Maximum Solenoid Duty Cycle - Warn if exceeded
FILTERWARN = 20   ; Pre-CII Filter Removal Alarm (seconds)
;
; Note: Set MAXDCYC = 100 to always supress warning
;
; DIAMOND RING/CONTACT II+III PARAMETERS
CIIOFF   = -1.2 ; Contact II offset from smooth dynamical limb
CIIIOFF  = -1.0 ; Contact III offset from smooth dynamical limb
DRNUM    = 9    ; Number of CII and CIII Diamond Ring Exposures (MUST be even)
DREXP    = 0.1  ; Duration (seconds) for Diamond Ring Exposures
DRSEQII  = -9,-8,-7,-6,-5,-4,-3,-2,-1 ; Delta-Times for DREXP wrt
DRSEQIII = 1,2,3,4,5,6,7,8,9 ; Delta-Times for DREXP Relative to CIII