[fitswcs] Status of WCS negotiations

[Mark Calabretta]

On Wed 1998/07/15 14:36:27 -0400, Don Wells wrote
in a message to: fitswcs at fits.cv.nrao.edu

>that we need to implement support for the function widely. I say
>'pixel correction function' because I myself favor perturbing the
>pixel coordinates before applying the linear transformation. I am
>aware that other people prefer polynomial expansions in 'standard
>coordinates' or other functional forms. I hope that we can agree that
>these are mathematically equivalent notations. If any of you believe
>that there is some notational form which is clearly best, please post
>to 'fitswcs' on the subject so that I and others can learn about your
>ideas. If any of you strongly object to some particular notational
>form, please post your objection.  In the end we need to agree on a
>canonical *interchange* notation (we could continue to use private
>conventions in our software, of course).

Plate solutions can be implemented as projection types provided that the
number of projection parameters in G&C is increased.  After the last round of
email discussions on the topic I prepared a note suitable for inclusion in G&C
on how the projection used by the DSS would be handled.  I would also call on
optical astrometrists to specify more general optical plate solutions along
the same lines (or show that this approach is inadequate).  In general, I
view G&C as a framework on which new projection types can be built, either now
or later - better if now since the projection, including the projection codes
assigned, will gain more widespread currency.  Note that plate solution
projection types can co-exist with Pat Wallace's pixel regularization table
(if this is what optical astrometrists want).  The PostScript for the "DSS"
projection is appended.

I have an experimental version of the C incarnation of WCSLIB which handles
100 projection parameters and also the "DSS" projection type.  The change to
the C library for additional projection parameters was isolated to the header
file and should only require a recompile on the part of third-parties.
However, the FORTRAN library would require changing the interfaces and I am
reluctant to do this without general agreement that it would be supported.
If anyone would like to see the C implementation (260 lines of C code appended
to proj.c) I'd be happy to send it.

Mark Calabretta

>>>

%!PS-Adobe-2.0
%%Creator: dvipsk 5.58f Copyright 1986, 1994 Radical Eye Software
%%Title: dss.dvi
%%Pages: 2
%%PageOrder: Ascend
%%BoundingBox: 0 0 596 842
%%DocumentPaperSizes: A4 (double-sided)
%%EndComments
%DVIPSCommandLine: dvips -o dss.ps dss.dvi
%DVIPSParameters: dpi=300, comments removed
%DVIPSSource:  TeX output 1997.03.24:1608
%%BeginProcSet: tex.pro
/TeXDict 250 dict def TeXDict begin /N{def}def /B{bind def}N /S{exch}N
/X{S N}B /TR{translate}N /isls false N /vsize 11 72 mul N /hsize 8.5 72
mul N /landplus90{false}def /@rigin{isls{[0 landplus90{1 -1}{-1 1}
ifelse 0 0 0]concat}if 72 Resolution div 72 VResolution div neg scale
isls{landplus90{VResolution 72 div vsize mul 0 exch}{Resolution -72 div
hsize mul 0}ifelse TR}if Resolution VResolution vsize -72 div 1 add mul
TR[matrix currentmatrix{dup dup round sub abs 0.00001 lt{round}if}
forall round exch round exch]setmatrix}N /@landscape{/isls true N}B
/@manualfeed{statusdict /manualfeed true put}B /@copies{/#copies X}B
/FMat[1 0 0 -1 0 0]N /FBB[0 0 0 0]N /nn 0 N /IE 0 N /ctr 0 N /df-tail{
/nn 8 dict N nn begin /FontType 3 N /FontMatrix fntrx N /FontBBox FBB N
string /base X array /BitMaps X /BuildChar{CharBuilder}N /Encoding IE N
end dup{/foo setfont}2 array copy cvx N load 0 nn put /ctr 0 N[}B /df{
/sf 1 N /fntrx FMat N df-tail}B /dfs{div /sf X /fntrx[sf 0 0 sf neg 0 0]
N df-tail}B /E{pop nn dup definefont setfont}B /ch-width{ch-data dup
length 5 sub get}B /ch-height{ch-data dup length 4 sub get}B /ch-xoff{
128 ch-data dup length 3 sub get sub}B /ch-yoff{ch-data dup length 2 sub
get 127 sub}B /ch-dx{ch-data dup length 1 sub get}B /ch-image{ch-data
dup type /stringtype ne{ctr get /ctr ctr 1 add N}if}B /id 0 N /rw 0 N
/rc 0 N /gp 0 N /cp 0 N /G 0 N /sf 0 N /CharBuilder{save 3 1 roll S dup
/base get 2 index get S /BitMaps get S get /ch-data X pop /ctr 0 N ch-dx
0 ch-xoff ch-yoff ch-height sub ch-xoff ch-width add ch-yoff
setcachedevice ch-width ch-height true[1 0 0 -1 -.1 ch-xoff sub ch-yoff
.1 sub]{ch-image}imagemask restore}B /D{/cc X dup type /stringtype ne{]}
if nn /base get cc ctr put nn /BitMaps get S ctr S sf 1 ne{dup dup
length 1 sub dup 2 index S get sf div put}if put /ctr ctr 1 add N}B /I{
cc 1 add D}B /bop{userdict /bop-hook known{bop-hook}if /SI save N @rigin
0 0 moveto /V matrix currentmatrix dup 1 get dup mul exch 0 get dup mul
add .99 lt{/QV}{/RV}ifelse load def pop pop}N /eop{SI restore userdict
/eop-hook known{eop-hook}if showpage}N /@start{userdict /start-hook
known{start-hook}if pop /VResolution X /Resolution X 1000 div /DVImag X
/IE 256 array N 0 1 255{IE S 1 string dup 0 3 index put cvn put}for
65781.76 div /vsize X 65781.76 div /hsize X}N /p{show}N /RMat[1 0 0 -1 0
0]N /BDot 260 string N /rulex 0 N /ruley 0 N /v{/ruley X /rulex X V}B /V
{}B /RV statusdict begin /product where{pop product dup length 7 ge{0 7
getinterval dup(Display)eq exch 0 4 getinterval(NeXT)eq or}{pop false}
ifelse}{false}ifelse end{{gsave TR -.1 .1 TR 1 1 scale rulex ruley false
RMat{BDot}imagemask grestore}}{{gsave TR -.1 .1 TR rulex ruley scale 1 1
false RMat{BDot}imagemask grestore}}ifelse B /QV{gsave newpath transform
round exch round exch itransform moveto rulex 0 rlineto 0 ruley neg
rlineto rulex neg 0 rlineto fill grestore}B /a{moveto}B /delta 0 N /tail
{dup /delta X 0 rmoveto}B /M{S p delta add tail}B /b{S p tail}B /c{-4 M}
B /d{-3 M}B /e{-2 M}B /f{-1 M}B /g{0 M}B /h{1 M}B /i{2 M}B /j{3 M}B /k{
4 M}B /w{0 rmoveto}B /l{p -4 w}B /m{p -3 w}B /n{p -2 w}B /o{p -1 w}B /q{
p 1 w}B /r{p 2 w}B /s{p 3 w}B /t{p 4 w}B /x{0 S rmoveto}B /y{3 2 roll p
a}B /bos{/SS save N}B /eos{SS restore}B end
%%EndProcSet
TeXDict begin 39158280 55380996 1000 300 300 (dss.dvi)
@start /Fa 3 77 df<FF80FF80FF0009037D880E>45 D<0000200000600000E00000E0
0001E00001F0000270000270000470000870000870001070001070002070004070004070
00803800FFF8010038020038020038040038040038080038180038FE01FF181A7E991D>
65 D<03FF0000700000700000700000E00000E00000E00000E00001C00001C00001C000
01C0000380000380000380000380000700000700100700100700200E00200E00600E0040
0E00C01C0380FFFF80141A7D9918>76 D E /Fb 1 66 df<00C00000C00001E000016000
016000023000023000023000041800041800080C000FFC00080C00100600100600300700
FC1FC012117F9016>65 D E /Fc 14 117 df<FFC0FFC0FFC00A037D890F>45
D<01E307170C0F180F380E300E700E700EE01CE01CE01CE01CE039E039E0396079319A1E
0C10127C9115>97 D<3F00070007000E000E000E000E001C001C001C001C0039E03A183C
0C380C700C700E700E700EE01CE01CE01CE018E038E030E06060C031801E000F1D7C9C13
>I<00F803040E041C0E181C300070007000E000E000E000E000E000E004600860103060
0F800F127C9113>I<0007E00000E00000E00001C00001C00001C00001C0000380000380
00038000038001E7000717000C0F00180F00380E00300E00700E00700E00E01C00E01C00
E01C00E01C00E03900E03900E03900607900319A001E0C00131D7C9C15>I<00F807040C
0418023804300470087FF0E000E000E000E000E00060046008301030600F800F127C9113
>I<0003C0000670000C70001C60001C00001C0000380000380000380000380000380003
FF8000700000700000700000700000700000E00000E00000E00000E00000E00001C00001
C00001C00001C00001C000038000038000038000030000030000070000C60000E60000CC
00007800001425819C0D>I<0FC00001C00001C000038000038000038000038000070000
0700000700000700000E3E000EC3000F03800E03801E03801C03801C03801C0380380700
380700380700380E00700E40700E40701C40701C80E00C80600700121D7E9C15>104
D<1F800380038007000700070007000E000E000E000E001C001C001C001C003800380038
0038007000700070007000E200E200E200E40064003800091D7D9C0B>108
D<1C1E0780266318C04683A0E04703C0E08E0380E08E0380E00E0380E00E0380E01C0701
C01C0701C01C0701C01C070380380E0388380E0388380E0708380E0710701C0320300C01
C01D127C9122>I<383E004CC3004D03804E03809E03809C03801C03801C038038070038
0700380700380E00700E40700E40701C40701C80E00C8060070012127C9117>I<00F800
030C000E06001C0300180300300300700380700380E00700E00700E00700E00E00E00E00
E01C0060180060300030E0000F800011127C9115>I<1C3C2642468747078E068E000E00
0E001C001C001C001C0038003800380038007000300010127C9112>114
D<03000700070007000E000E000E000E00FFE01C001C001C003800380038003800700070
0070007000E080E080E100E100660038000B1A7C990E>116 D E
/Fd 31 91 df<387C7E7E3E0E1E1C78F060070B798416>44 D<70F8F8F8700505788416>
46 D<03E0000FF8001FFC001E3C00380E00780F00700700700700E00380E00380E00380
E00380E00380E00380E00380E00380F00780700700700700780F003C1E001E3C001FFC00
0FF80003E00011197E9816>48 D<0300070007000F001F00FF00FF00E700070007000700
07000700070007000700070007000700070007000700FFF8FFF8FFF80D197B9816>I<07
E0001FF8003FFC00783E00E00700F00780F0038060038000038000038000070000070000
0E00001C0000380000700000E00001C0000380000F00001E03803803807FFF80FFFF807F
FF8011197E9816>I<07E0001FF8003FFC00781E00780700300700000700000700000E00
003E0007FC0007F00007FC00001E00000700000300000380000380600380F00380E00700
781E003FFC001FF80007E00011197E9816>I<3FFE007FFE007FFE007000007000007000
0070000070000070000070000077F0007FFC007FFE00780F003007000003800003806003
80F00380F00380E00700781E003FFC001FF80007E00011197E9816>53
D<00F80003FC0007FE000F07001C0F00380F00780600700000700000E3F800EFFC00FFFE
00F80F00F00700F00380E00380E003807003807003807007803807003C1E001FFC000FF8
0003E00011197E9816>I<00E00001F00001F00001B00001B00003B80003B80003B80003
1800071C00071C00071C00071C00071C000E0E000E0E000FFE000FFE001FFF001C07001C
07001C07007E0FC0FF1FE07E0FC013197F9816>65 D<01F18007FB800FFF801F0F803C07
80380380700380700380F00000E00000E00000E00000E00000E00000E00000E00000F000
007003807003803803803C07001F0F000FFE0007FC0001F00011197E9816>67
D<7FF800FFFE007FFF001C0F001C07801C03C01C01C01C01C01C01E01C00E01C00E01C00
E01C00E01C00E01C00E01C00E01C00E01C01C01C01C01C03C01C07801C0F807FFF00FFFE
007FF8001319809816>I<7FFFC0FFFFC07FFFC01C01C01C01C01C01C01C01C01C00001C
00001C1C001C1C001FFC001FFC001FFC001C1C001C1C001C00001C00E01C00E01C00E01C
00E01C00E07FFFE0FFFFE07FFFE013197F9816>I<7FFFE0FFFFE07FFFE01C00E01C00E0
1C00E01C00E01C00001C00001C1C001C1C001FFC001FFC001FFC001C1C001C1C001C0000
1C00001C00001C00001C00001C00007F8000FFC0007F800013197F9816>I<7F07F0FF8F
F87F07F01C01C01C01C01C01C01C01C01C01C01C01C01C01C01FFFC01FFFC01FFFC01C01
C01C01C01C01C01C01C01C01C01C01C01C01C01C01C01C01C07F07F0FF8FF87F07F01519
809816>72 D<7FFCFFFE7FFC038003800380038003800380038003800380038003800380
03800380038003800380038003807FFCFFFE7FFC0F197D9816>I<01FF0003FF8001FF00
001C00001C00001C00001C00001C00001C00001C00001C00001C00001C00001C00001C00
001C00001C00001C00001C00601C00F01C00F038007FF8007FF0001FC00011197E9816>
I<7F0FE0FF8FF07F0FE01C07801C0F001C0E001C1C001C3C001C78001CF0001CE0001DF0
001FF0001FF8001F38001E1C001C1C001C0E001C0E001C07001C07001C03807F07E0FF8F
F07F07E01419809816>I<FF8000FFC000FF80001C00001C00001C00001C00001C00001C
00001C00001C00001C00001C00001C00001C00001C00001C00001C00401C00E01C00E01C
00E01C00E0FFFFE0FFFFE0FFFFE013197F9816>I<FC07E0FE0FE0FE0FE03A0B803B1B80
3B1B803B1B803B1B803B1B803BBB8039B38039B38039B38039B38039F38038E38038E380
380380380380380380380380380380FE0FE0FE0FE0FE0FE013197F9816>I<7E07F0FF0F
F87F07F01D81C01D81C01D81C01DC1C01CC1C01CE1C01CE1C01C61C01C71C01C71C01C71
C01C31C01C39C01C39C01C19C01C1DC01C0DC01C0DC01C0DC07F07C0FF87C07F03C01519
809816>I<1FFC003FFE007FFF00780F00F00780E00380E00380E00380E00380E00380E0
0380E00380E00380E00380E00380E00380E00380E00380E00380F00780F00780780F007F
FF003FFE001FFC0011197E9816>I<7FF800FFFE007FFF001C0F801C03801C03C01C01C0
1C01C01C01C01C03C01C03801C0F801FFF001FFE001FF8001C00001C00001C00001C0000
1C00001C00001C00007F0000FF80007F000012197F9816>I<1FFC003FFE007FFF00780F
00F00780E00380E00380E00380E00380E00380E00380E00380E00380E00380E00380E003
80E00380E00380E0E380E1E380F0F780787F007FFF003FFE001FFC00001C00001E00000E
00000F00000700000700111F7E9816>I<7FF000FFFC007FFE001C0F001C07801C03801C
03801C03801C03801C07801C0F001FFE001FFC001FFE001C0E001C07001C07001C07001C
07001C07101C07381C07387F03F0FF83F07F01E01519809816>I<07E3001FFF003FFF00
781F00F00700E00700E00700E00000F000007800003F80001FF00007FC0000FE00000F00
000700000380000380600380E00380E00700F80F00FFFE00FFFC00C7F00011197E9816>
I<7FFFE0FFFFE0FFFFE0E0E0E0E0E0E0E0E0E0E0E0E000E00000E00000E00000E00000E0
0000E00000E00000E00000E00000E00000E00000E00000E00000E00000E00007FC000FFE
0007FC0013197F9816>I<7F07F0FF8FF87F07F01C01C01C01C01C01C01C01C01C01C01C
01C01C01C01C01C01C01C01C01C01C01C01C01C01C01C01C01C01C01C01C01C00E03800E
038007070007FF0003FE0000F8001519809816>I<FE0FE0FE0FE0FE0FE03803803C0780
1C07001C07001C07001E0F000E0E000E0E000E0E000E0E00071C00071C00071C00071C00
03180003B80003B80003B80001B00001F00001F00000E00013197F9816>I<7F1F807F3F
C07F1F800E1E000E1C00071C0007380003B80003F00001F00001E00000E00001E00001F0
0003F00003B80007B800071C000F1C000E0E000E0E001C07007E0FC0FF1FE07E0FC01319
7F9816>88 D<FE0FE0FF1FE0FE0FE01C07001C07000E0E000E0E00071C00071C00071C00
03B80003B80001F00001F00000E00000E00000E00000E00000E00000E00000E00000E000
03F80007FC0003F80013197F9816>I<7FFF80FFFF80FFFF80E00700E00F00E01E00E01C
00003C0000780000700000F00001E00001C00003C0000780000700000F00001E03801C03
803C0380780380700380FFFF80FFFF80FFFF8011197E9816>I E
/Fe 1 1 df<FFFFC0FFFFC012027D871A>0 D E /Ff 5 113 df<002000400080010003
00060006000C000C00180018003800300030007000700070006000E000E000E000E000E0
00E000E000E000E000E000E000E000E0006000700070007000300030003800180018000C
000C0006000600030001000080004000200B317A8113>0 D<800040002000100018000C
000C00060006000300030003800180018001C001C001C000C000E000E000E000E000E000
E000E000E000E000E000E000E000E000C001C001C001C001800180038003000300060006
000C000C00180010002000400080000B317F8113>I<FF80FF80C000C000C000C000C000
C000C000C000C000C000C000C000C000C000C000C000C000C000C000C000C000C000C000
C000C000C000C000C000C000C000C000C000C000C000C000C000C000C000C000C000C000
C000C000C000C000C000C000C000C000C000C000C000C000C000C000C000C000C000C000
C000C000C000C000C000C000C000C000C000C000C000FF80FF80094A778114>104
D<FF80FF8001800180018001800180018001800180018001800180018001800180018001
800180018001800180018001800180018001800180018001800180018001800180018001
800180018001800180018001800180018001800180018001800180018001800180018001
800180018001800180018001800180018001800180018001800180018001800180018001
80FF80FF80094A7F8114>I<00000000020000000006000000000C000000000C00000000
180000000018000000003000000000300000000060000000006000000000C000000000C0
0000000180000000018000000003000000000300000000060000000006000000000C0000
00000C000000001800000000180000000030000000003000000000600008000060001C00
00C0003C0000C000CE000180000E000180000E0003000007000300000700060000038006
000003800C000001C00C000001C018000001E018000000E030000000E030000000706000
0000706000000038C000000038C00000001D800000001D800000001F000000000F000000
000E000000000600000027327C812A>112 D E /Fg 10 58 df<0F0030C0606060604020
C030C030C030C030C030C030C030C030C03040206060606030C00F000C137E9211>48
D<0C001C00EC000C000C000C000C000C000C000C000C000C000C000C000C000C000C000C
00FFC00A137D9211>I<1F0060C06060F070F030603000700070006000C001C001800200
04000810101020207FE0FFE00C137E9211>I<0FC030707038703870380038003000E00F
C0007000380018001C601CF01CF018E03860701FC00E137F9211>I<006000E000E00160
026006600C600860106020606060C060FFFC0060006000600060006003FC0E137F9211>
I<60607FC07F8044004000400040004F0070C040E0006000700070E070E070E06040E021
C01F000C137E9211>I<07C00C201070207060006000C000CF00D0C0E060C020C030C030
C03040306020206010C00F000C137E9211>I<40007FFC7FF84010803080200040008001
00010003000200060006000E000E000E000E000E0004000E147E9311>I<0FC010702018
6018601870183C303F600F800FE031F06078C01CC00CC00CC00C601830300FC00E137F92
11>I<0F00308060404060C020C030C030C0304030607030B00F30003000200060E040E0
8041003E000C137E9211>I E /Fh 3 104 df<FFFFFF80FFFFFF8019027D8A20>0
D<003C00E001C00180038003800380038003800380038003800380038003800380038003
0007001C00F0001C00070003000380038003800380038003800380038003800380038003
800380018001C000E0003C0E297D9E15>102 D<F0001C00070003000380038003800380
038003800380038003800380038003800380018001C000E0003C00E001C0018003800380
03800380038003800380038003800380038003800380030007001C00F0000E297D9E15>
I E /Fi 3 122 df<03C00C20187030E0600060006000C000C0004010602030C01F000C
0D7F8C0F>99 D<0E3C13CE238E430C43000300030006000608C608E610CA2071C00F0D7F
8C13>120 D<380C4C0C4C0C8C18981818181818303030303030307018E00F60006000C0
E0C0E18043003C000E137F8C11>I E /Fj 23 122 df<00F800030C000E06041C070438
0308300388700390700390E003A0E003A0E003C0E00380E00380E00380600780600B8830
71900F80E016127E911B>11 D<003800007F0000878001030001000001800001800001C0
0000C00000E00000E00000700000F80003B800063C000C1C00181C00381C00701C00701C
00E01C00E01C00E01C00E01C00E01800E0380060300070600038C0000F8000111E7F9D12
>14 D<3C1F004E61804681C04701C08F01C08E01C00E01C00E01C01C03801C03801C0380
1C0380380700380700380700380700700E00300E00000E00000E00001C00001C00001C00
001C00003800003800003000121B7E9115>17 D<007800CC0186030606060E060C061C07
180738063806300E700E700E7FFEE01CE01CE01CE018E038C038C070C060C060C0C0C180
618062003C00101D7E9C13>I<0180300380700380700380700700E00700E00700E00700
E00E01C00E01C00E01C00E01C01C03881C03881C03881E07883E19903BE0E03800003800
00700000700000700000700000E00000E00000C00000151B7F9119>22
D<001000001000001000001F8000F08001CF000380000700000E00000E00000E00000E00
000E00000E000006FC0003840006FC00080000180000300000200000600000600000E000
00E00000E000007000007C00003F80001FE00003F80000FC00001E00000E00000C000108
0000F0001125809C12>24 D<0FFFF81FFFF83FFFF8608400418400810400010400030C00
030C00020C00060C00060C000E0C000C0C001C0E001C0E00380E0018060015127E9118>
I<000100000200000200000200000200000400000400000400000400000800000800007E
0001C9800710E00C1060181070381030702030702030E02070E02070E04070E040E0E040
E06041C06083803086001C9C0007E0000100000100000100000100000200000200000200
0002000014257E9C19>30 D<60F0F06004047C830C>58 D<60F0F0701010101020204080
040C7C830C>I<00010003000600060006000C000C000C00180018001800300030003000
60006000C000C000C0018001800180030003000300060006000C000C000C001800180018
00300030003000600060006000C000C00010297E9E15>61 D<003E0000C3000100C00200
C003006007806007807003003000003000003000003000FC700382700601700C01701800
F03800E03000E07000E07001C0E001C0E001C0E00180E00380E00300E00600E00600600C
003018001860000F8000141F7E9D16>64 D<01FFC0003C00003800003800003800003800
00700000700000700000700000E00000E00000E00000E00001C00001C00001C00001C000
0380000380000380000380000700000700000700000700000F0000FFE000121C7E9B12>
73 D<001FFC0001E00001C00001C00001C00001C0000380000380000380000380000700
000700000700000700000E00000E00000E00000E00001C00001C00001C00201C00703800
F03800E0300080700040E0006180001F0000161D7D9B17>I<01FFC0FF80001E003C0000
1C003000000E002000000E004000000F0080000007010000000782000000038400000003
CC00000001D800000001F000000001E000000000E000000000F000000001700000000278
00000004380000000838000000103C000000201C000000401E000000800E000001000F00
00020007000006000700001E000F8000FF803FF000211C7F9B22>88
D<FFE007F80F0001E00F0001800F00010007000200078004000380080003C0180003C010
0001C0200001E0400000E0800000F1000000F2000000760000007C000000380000003800
000070000000700000007000000070000000E0000000E0000000E0000000E0000001C000
001FFC00001D1C7F9B18>I<01E3000717000C0F00180F00380E00300E00700E00700E00
E01C00E01C00E01C00E01C00E03880E03880E038806078803199001E0E0011127E9116>
97 D<3F00070007000E000E000E000E001C001C001C001C0039E03A303C183818701870
1C701C701CE038E038E038E030E070E060E0C061C023001E000E1D7E9C12>I<01C003C0
03C001800000000000000000000000001C00270047004700870087000E000E001C001C00
1C003800388038807080710032001C000A1C7E9B0E>105 D<0007000F000F0006000000
0000000000000000000078009C010C020C021C041C001C001C0038003800380038007000
700070007000E000E000E000E001C061C0F180F300E6007C001024809B11>I<07878009
C86008D03008E03011C03011C03801C03801C0380380700380700380700380600700E007
00C00701800783000E86000E78000E00000E00001C00001C00001C00001C00003C0000FF
0000151A819115>112 D<07878008C84010F0C020F1E020E3C040E18000E00000E00001
C00001C00001C00001C000638080F38080F38100E5810084C60078780013127E9118>
120 D<1C00C02701C04701C04701C08703808703800E03800E03801C07001C07001C0700
1C0700180E00180E00180E001C1E000C3C0007DC00001C00001800603800F03000F06000
E0C0004180003E0000121A7E9114>I E /Fk 68 123 df<007E1F0001C1B1800303E3C0
0703C3C00E03C1800E01C0000E01C0000E01C0000E01C0000E01C0000E01C000FFFFFC00
0E01C0000E01C0000E01C0000E01C0000E01C0000E01C0000E01C0000E01C0000E01C000
0E01C0000E01C0000E01C0000E01C0000E01C0000E01C0000E01C0007F87FC001A1D809C
18>11 D<007E0001C1800301800703C00E03C00E01800E00000E00000E00000E00000E00
00FFFFC00E01C00E01C00E01C00E01C00E01C00E01C00E01C00E01C00E01C00E01C00E01
C00E01C00E01C00E01C00E01C00E01C07F87F8151D809C17>I<003F07E00001C09C1800
0380F018000701F03C000E01E03C000E00E018000E00E000000E00E000000E00E000000E
00E000000E00E00000FFFFFFFC000E00E01C000E00E01C000E00E01C000E00E01C000E00
E01C000E00E01C000E00E01C000E00E01C000E00E01C000E00E01C000E00E01C000E00E0
1C000E00E01C000E00E01C000E00E01C000E00E01C007FC7FCFF80211D809C23>14
D<6060F0F0F8F86868080808080808101010102020404080800D0C7F9C15>34
D<00800100020006000C000C00180018003000300030006000600060006000E000E000E0
00E000E000E000E000E000E000E000E000E0006000600060006000300030003000180018
000C000C000600020001000080092A7C9E10>40 D<8000400020003000180018000C000C
000600060006000300030003000300038003800380038003800380038003800380038003
80038003000300030003000600060006000C000C00180018003000200040008000092A7E
9E10>I<0006000000060000000600000006000000060000000600000006000000060000
0006000000060000000600000006000000060000FFFFFFE0FFFFFFE00006000000060000
000600000006000000060000000600000006000000060000000600000006000000060000
00060000000600001B1C7E9720>43 D<60F0F0701010101020204080040C7C830C>I<FF
E0FFE00B0280890E>I<60F0F06004047C830C>I<00010003000600060006000C000C000C
0018001800180030003000300060006000C000C000C00180018001800300030003000600
06000C000C000C00180018001800300030003000600060006000C000C00010297E9E15>
I<03C00C301818300C300C700E60066006E007E007E007E007E007E007E007E007E007E0
07E007E007E00760066006700E300C300C18180C3007E0101D7E9B15>I<010007003F00
C70007000700070007000700070007000700070007000700070007000700070007000700
070007000700070007000700FFF80D1C7C9B15>I<07C01830201C400C400EF00FF80FF8
07F8077007000F000E000E001C001C00380070006000C00180030006010C01180110023F
FE7FFEFFFE101C7E9B15>I<07E01830201C201C781E780E781E381E001C001C00180030
006007C00030001C001C000E000F000F700FF80FF80FF80FF00E401C201C183007C0101D
7E9B15>I<000C00000C00001C00003C00003C00005C0000DC00009C00011C00031C0002
1C00041C000C1C00081C00101C00301C00201C00401C00C01C00FFFFC0001C00001C0000
1C00001C00001C00001C00001C0001FFC0121C7F9B15>I<300C3FF83FF03FC020002000
200020002000200023E02C303018301C200E000E000F000F000F600FF00FF00FF00F800E
401E401C2038187007C0101D7E9B15>I<00F0030C04040C0E181E301E300C7000700060
00E3E0E430E818F00CF00EE006E007E007E007E007E007600760077006300E300C18180C
3003E0101D7E9B15>I<4000007FFF807FFF007FFF004002008004008004008008000010
0000100000200000600000400000C00000C00001C0000180000180000380000380000380
00038000078000078000078000078000078000078000030000111D7E9B15>I<03E00C30
1008200C200660066006700670067C0C3E183FB01FE007F007F818FC307E601E600FC007
C003C003C003C00360026004300C1C1007E0101D7E9B15>I<03C00C301818300C700C60
0EE006E006E007E007E007E007E0076007700F300F18170C2707C700060006000E300C78
0C78187018203010C00F80101D7E9B15>I<7FFFFFC0FFFFFFE000000000000000000000
00000000000000000000000000000000000000000000FFFFFFE07FFFFFC01B0C7E8F20>
61 D<000600000006000000060000000F0000000F0000000F0000001780000017800000
37C0000023C0000023C0000043E0000041E0000041E0000080F0000080F0000080F00001
0078000100780001FFF80002003C0002003C0002003C0004001E0004001E000C001F000C
000F001E001F00FF00FFF01C1D7F9C1F>65 D<001F808000E0618001801980070007800E
0003801C0003801C00018038000180780000807800008070000080F0000000F0000000F0
000000F0000000F0000000F0000000F0000000F000000070000080780000807800008038
0000801C0001001C0001000E000200070004000180080000E03000001FC000191E7E9C1E
>67 D<FFFFC0000F00F0000F003C000F000E000F0007000F0007000F0003800F0003C00F
0001C00F0001C00F0001E00F0001E00F0001E00F0001E00F0001E00F0001E00F0001E00F
0001E00F0001C00F0001C00F0003C00F0003800F0007800F0007000F000E000F001C000F
007000FFFFC0001B1C7E9B20>I<FFFFFC0F003C0F000C0F00040F00040F00060F00020F
00020F01020F01000F01000F01000F03000FFF000F03000F01000F01000F01000F01010F
00010F00020F00020F00020F00060F00060F000C0F003CFFFFFC181C7E9B1C>I<FFFFF8
0F00780F00180F00080F00080F000C0F00040F00040F01040F01000F01000F01000F0300
0FFF000F03000F01000F01000F01000F01000F00000F00000F00000F00000F00000F0000
0F00000F0000FFF800161C7E9B1B>I<001F808000E0618001801980070007800E000380
1C0003801C00018038000180780000807800008070000080F0000000F0000000F0000000
F0000000F0000000F0000000F000FFF0F0000F8070000780780007807800078038000780
1C0007801C0007800E00078007000B800180118000E06080001F80001C1E7E9C21>I<FF
F0FFF00F000F000F000F000F000F000F000F000F000F000F000F000F000F000F000F000F
000F000F000F000F000F000F000F000FFFFF000F000F000F000F000F000F000F000F000F
000F000F000F000F000F000F000F000F000F000F000F000F000F000F000F000F000F00FF
F0FFF01C1C7F9B1F>I<FFF00F000F000F000F000F000F000F000F000F000F000F000F00
0F000F000F000F000F000F000F000F000F000F000F000F000F000F00FFF00C1C7F9B0F>
I<07FF80007C00003C00003C00003C00003C00003C00003C00003C00003C00003C00003C
00003C00003C00003C00003C00003C00003C00003C00003C00003C00703C00F83C00F83C
00F8380070780040700030E0000F8000111D7F9B15>I<FFF01FE00F0007800F0006000F
0004000F0008000F0010000F0020000F0040000F0080000F0100000F0200000F0600000F
0F00000F1780000F2780000F43C0000F81E0000F01E0000F00F0000F0078000F0078000F
003C000F003E000F001E000F000F000F000F800F000FC0FFF03FF01C1C7F9B20>I<FF80
00FF800F8000F8000F8000F8000BC00178000BC00178000BC001780009E002780009E002
780008F004780008F004780008F0047800087808780008780878000878087800083C1078
00083C107800083C107800081E207800081E207800081E207800080F407800080F407800
08078078000807807800080780780008030078001C03007800FF8307FF80211C7E9B26>
77 D<003F800000E0E0000380380007001C000E000E001C0007003C0007803800038078
0003C0780003C0700001C0F00001E0F00001E0F00001E0F00001E0F00001E0F00001E0F0
0001E0F00001E0700001C0780003C0780003C0380003803C0007801C0007000E000E0007
001C000380380000E0E000003F80001B1E7E9C20>79 D<FFFF800F00E00F00780F003C0F
001C0F001E0F001E0F001E0F001E0F001E0F001C0F003C0F00780F00E00FFF800F00000F
00000F00000F00000F00000F00000F00000F00000F00000F00000F00000F0000FFF00017
1C7E9B1C>I<FFFF00000F01E0000F0078000F003C000F001C000F001E000F001E000F00
1E000F001E000F001C000F003C000F0078000F01E0000FFF00000F01E0000F0070000F00
78000F003C000F003C000F003C000F003C000F003C000F003C000F003C100F003C100F00
1C100F001C10FFF00E20000003C01C1D7E9B1F>82 D<07E0801C19803005803003806001
80E00180E00080E00080E00080F00000F800007C00007FC0003FF8001FFE0007FF0000FF
80000F800007C00003C00001C08001C08001C08001C0C00180C00180E00300D00200CC0C
0083F800121E7E9C17>I<7FFFFFC0700F01C0600F00C0400F0040400F0040C00F002080
0F0020800F0020800F0020000F0000000F0000000F0000000F0000000F0000000F000000
0F0000000F0000000F0000000F0000000F0000000F0000000F0000000F0000000F000000
0F0000000F0000001F800003FFFC001B1C7F9B1E>I<FFF01FF00F0003800F0001000F00
01000F0001000F0001000F0001000F0001000F0001000F0001000F0001000F0001000F00
01000F0001000F0001000F0001000F0001000F0001000F0001000F0001000F0001000F00
010007000200078002000380040001C0040000E0180000706000000F80001C1D7F9B1F>
I<FEFEC0C0C0C0C0C0C0C0C0C0C0C0C0C0C0C0C0C0C0C0C0C0C0C0C0C0C0C0C0C0C0C0C0
C0C0C0C0FEFE07297C9E0C>91 D<08081010202040404040808080808080B0B0F8F87878
30300D0C7A9C15>I<FEFE06060606060606060606060606060606060606060606060606
060606060606060606060606FEFE0729809E0C>I<1FC000307000783800781C00301C00
001C00001C0001FC000F1C00381C00701C00601C00E01C40E01C40E01C40603C40304E80
1F870012127E9115>97 D<FC00001C00001C00001C00001C00001C00001C00001C00001C
00001C00001C00001C7C001D87001E01801C00C01C00E01C00601C00701C00701C00701C
00701C00701C00701C00601C00E01C00C01E018019070010FC00141D7F9C17>I<03F80C
0C181E301E700C6000E000E000E000E000E000E00060007002300218040C1803E00F127F
9112>I<001F800003800003800003800003800003800003800003800003800003800003
8003F3800E0B80180780300380700380600380E00380E00380E00380E00380E00380E003
806003807003803003801807800E1B8003E3F0141D7F9C17>I<07E00C301818300C700E
6006E006FFFEE000E000E000E00060007002300218040C1803E00F127F9112>I<00F801
8C071E061E0E0C0E000E000E000E000E000E00FFE00E000E000E000E000E000E000E000E
000E000E000E000E000E000E000E000E007FE00F1D809C0D>I<00038007C4C01C78C038
3880301800701C00701C00701C00701C003018003838001C700027C00020000020000030
00003FF8001FFF001FFF802003806001C0C000C0C000C0C000C06001803003001C0E0007
F800121C7F9215>I<FC00001C00001C00001C00001C00001C00001C00001C00001C0000
1C00001C00001C7C001C87001D03001E03801C03801C03801C03801C03801C03801C0380
1C03801C03801C03801C03801C03801C03801C0380FF9FF0141D7F9C17>I<18003C003C
0018000000000000000000000000000000FC001C001C001C001C001C001C001C001C001C
001C001C001C001C001C001C001C00FF80091D7F9C0C>I<00C001E001E000C000000000
0000000000000000000007E000E000E000E000E000E000E000E000E000E000E000E000E0
00E000E000E000E000E000E000E000E060E0F0C0F1C061803E000B25839C0D>I<FC0000
1C00001C00001C00001C00001C00001C00001C00001C00001C00001C00001C0FE01C0780
1C06001C0C001C10001C20001C40001CE0001DE0001E70001C78001C38001C3C001C1C00
1C0E001C0F001C0F80FF9FE0131D7F9C16>I<FC001C001C001C001C001C001C001C001C
001C001C001C001C001C001C001C001C001C001C001C001C001C001C001C001C001C001C
001C00FF80091D7F9C0C>I<FC7E07E0001C838838001D019018001E01E01C001C01C01C
001C01C01C001C01C01C001C01C01C001C01C01C001C01C01C001C01C01C001C01C01C00
1C01C01C001C01C01C001C01C01C001C01C01C001C01C01C00FF8FF8FF8021127F9124>
I<FC7C001C87001D03001E03801C03801C03801C03801C03801C03801C03801C03801C03
801C03801C03801C03801C03801C0380FF9FF014127F9117>I<03F0000E1C0018060030
0300700380600180E001C0E001C0E001C0E001C0E001C0E001C060018070038030030018
06000E1C0003F00012127F9115>I<FC7C001D87001E01801C01C01C00E01C00E01C0070
1C00701C00701C00701C00701C00701C00E01C00E01C01C01E01801D07001CFC001C0000
1C00001C00001C00001C00001C00001C0000FF8000141A7F9117>I<03E0800E19801805
80380780700380700380E00380E00380E00380E00380E00380E003807003807003803807
801807800E1B8003E380000380000380000380000380000380000380000380001FF0141A
7F9116>I<FCE01D381E781E781C301C001C001C001C001C001C001C001C001C001C001C
001C00FFC00D127F9110>I<1F9020704030C010C010E010F8007F803FE00FF000F88038
8018C018C018E010D0608FC00D127F9110>I<04000400040004000C000C001C003C00FF
E01C001C001C001C001C001C001C001C001C001C101C101C101C101C100C100E2003C00C
1A7F9910>I<FC1F801C03801C03801C03801C03801C03801C03801C03801C03801C0380
1C03801C03801C03801C03801C07800C07800E1B8003E3F014127F9117>I<FF07E03C03
801C01001C01000E02000E02000F060007040007040003880003880003C80001D00001D0
0000E00000E00000E00000400013127F9116>I<FF3FC7E03C0703C01C0701801C070100
1C0B01000E0B82000E0B82000E1182000711C4000711C4000720C40003A0E80003A0E800
03C0680001C0700001C0700001803000008020001B127F911E>I<FF0FE01E07001C0600
0E040007080003900003B00001E00000E00000F00001F000013800021C00041C000C0E00
1807003C0780FE1FF014127F9116>I<FF07E03C03801C01001C01000E02000E02000F06
0007040007040003880003880003C80001D00001D00000E00000E00000E0000040000040
00008000008000F08000F10000F30000660000380000131A7F9116>I<7FFC7038603840
7040F040E041C003C0038007000F040E041C043C0C380870087038FFF80E127F9112>I
E /Fl 33 122 df<00FE000381000601800E03801C01001C00001C00001C00001C00001C
0000FFFF801C03801C03801C03801C03801C03801C03801C03801C03801C03801C03801C
03801C03801C03801C0380FF8FF0141A809915>12 D<01C0000003200000061000000E10
00000E1000000E1000000E1000000E2000000E4000000E40000007807F8007001E000700
0800078010000B80100011C0200031E0200060E0400060708000E0788000E03D0000E01E
0080E00E0080701F01003861C3000F807C00191A7E991E>38 D<FFC0FFC00A0280880D>
45 D<60F0F06004047D830B>I<03000700FF000700070007000700070007000700070007
00070007000700070007000700070007000700070007007FF80D187D9713>49
D<0F80106020304038803CC01CE01C401C003C003800380070006000C001800100020004
040804100430083FF87FF8FFF80E187E9713>I<07E01838201C601E700E201E001E001C
001C0038007007E00038001C000E000F000FE00FE00FC00F400E601C183807E010187F97
13>I<000C0000000C0000000C0000001E0000001E0000002F0000002700000027000000
43800000438000004380000081C0000081C0000181E0000100E0000100E00003FFF00002
0070000200700004003800040038000400380008001C0008001C003C001E00FF00FFC01A
1A7F991D>65 D<FFFFF80E00380E00180E00080E000C0E00040E00040E00040E01000E01
000E01000E03000FFF000E03000E01000E01000E01000E00020E00020E00020E00060E00
040E00040E000C0E003CFFFFFC171A7F991A>69 D<FFE0000E00000E00000E00000E0000
0E00000E00000E00000E00000E00000E00000E00000E00000E00000E00000E00000E0000
0E00080E00080E00080E00180E00100E00300E00700E00F0FFFFF0151A7F9918>76
D<0FC21836200E6006C006C002C002C002E00070007E003FE01FF803FC007E000E000700
03800380038003C002C006E004D81887E0101A7E9915>83 D<7FFFFF00701C0700401C01
00401C0100C01C0180801C0080801C0080801C0080001C0000001C0000001C0000001C00
00001C0000001C0000001C0000001C0000001C0000001C0000001C0000001C0000001C00
00001C0000001C0000001C0000001C000003FFE000191A7F991C>I<FF801FC01C000700
1C0006000E0004000E0004000E0004000700080007000800038010000380100003801000
01C0200001C0200000E0400000E0400000E0400000708000007080000079800000390000
00390000001E0000001E0000001E0000000C0000000C00001A1A7F991D>86
D<FFC0FF800F003C000F001000070020000380200003C0400001C0800000E1800000F100
00007A0000003E0000001C0000001E0000001E00000017000000278000004380000041C0
000081E0000100E0000300700002007800040038000C001C001E003E00FF007FC01A1A7F
991D>88 D<1FC000387000383800101C00001C00001C0003FC001E1C00381C00701C00E0
1C00E01C80E01C80E03C80705F801F8F0011107F8F13>97 D<FC00001C00001C00001C00
001C00001C00001C00001C00001C00001C00001CFC001D07001E03801C01C01C00C01C00
E01C00E01C00E01C00E01C00E01C00E01C01C01C01801E030019060010F800131A809915
>I<07F81C1C381C70087000E000E000E000E000E000E0007000700438081C1807E00E10
7F8F11>I<003F0000070000070000070000070000070000070000070000070000070003
E7000C1700180F00300700700700E00700E00700E00700E00700E00700E0070060070070
0700380F001C370007C7E0131A7F9915>I<07C01C3030187018600CE00CFFFCE000E000
E000E0006000700438081C1807E00E107F8F11>I<0FCF00187180303000703800703800
7038007038003030001860002FC0006000006000007000003FF0003FFC001FFE00600F00
C00300C00300C00300C00300600600381C0007E00011187F8F13>103
D<FC00001C00001C00001C00001C00001C00001C00001C00001C00001C00001C7C001D87
001E03801E03801C03801C03801C03801C03801C03801C03801C03801C03801C03801C03
801C0380FF9FF0141A809915>I<183C3C18000000000000FC1C1C1C1C1C1C1C1C1C1C1C
1C1C1CFF081A80990A>I<FC001C001C001C001C001C001C001C001C001C001C001C001C
001C001C001C001C001C001C001C001C001C001C001C001C00FF80091A80990A>108
D<FC7C001D87001E03801E03801C03801C03801C03801C03801C03801C03801C03801C03
801C03801C03801C0380FF9FF01410808F15>110 D<07E01C38300C700E6006E007E007
E007E007E007E0076006700E381C1C3807E010107F8F13>I<FCFC001D07001E03801C01
C01C01C01C00E01C00E01C00E01C00E01C00E01C00E01C01C01C01801E03001D06001CF8
001C00001C00001C00001C00001C00001C0000FF80001317808F15>I<FC781D9C1E1C1E
081C001C001C001C001C001C001C001C001C001C001C00FF800E10808F0F>114
D<1F2060E04020C020C020F0007F003FC01FE000F080708030C030C020F0408F800C107F
8F0F>I<0800080008000800180018003800FFC038003800380038003800380038003800
382038203820382018201C4007800B177F960F>I<FC1F801C03801C03801C03801C0380
1C03801C03801C03801C03801C03801C03801C03801C07800C07800E0B8003F3F0141080
8F15>I<FF0F803C07001C06001C04001C04000E08000E080007100007100007100003A0
0003A00001C00001C00001C00000800011107F8F14>I<FE7F1F80381C07003C1C06001C
0C04001C0E04000E1608000E1708000E170800072310000723900007A3900003C1A00003
C1E0000180C0000180C0000180C00019107F8F1C>I<FF0F803C07001C06001C04001C04
000E08000E080007100007100007100003A00003A00001C00001C00001C0000080000080
00010000010000E10000E20000E4000078000011177F8F14>121
D E end
%%EndProlog
%%BeginSetup
%%Feature: *Resolution 300dpi
TeXDict begin
%%BeginPaperSize: A4 (double-sided)
statusdict /a4tray known {statusdict begin a4tray end} stopped {} if
statusdict /setduplexmode known {statusdict begin true setduplexmode end} if
%%EndPaperSize

%%EndSetup
%%Page: 1 1
1 0 bop 937 -192 a Fl(1)-54 -93 y Fk(4.4.10)12 b(DSS)h(\(Digitized)h
(Sky)f(Surv)o(ey\))-54 -16 y(In)j(creating)h(the)g(Guide)f(Star)h
(Catalogue)e(for)i(the)g(Hubble)-116 34 y(Space)g(T)m(elescop)q(e)h
(\(HST\),)e(the)i(Space)f(T)m(elescop)q(e)h(Science)g(In-)-116
84 y(stitute)g(\(STScI\))g(digitized)e(the)i(optical)e(plates)i(of)e
(the)i(SER)o(C)-116 134 y(Southern)e(Sky)g(Surv)o(ey)g(obtained)g(b)o
(y)f(the)i(UK)f(Sc)o(hmidt)e(T)m(ele-)-116 184 y(scop)q(e)20
b(together)h(with)e(the)h(P)o(alomar)d(Observ)n(atory)j(Sky)g(Sur-)-116
233 y(v)o(ey)c(\(POSS\))i(of)e(the)h(northern)h(sky)e(obtained)h(b)o(y)
f(the)h(Osc)o(hin)-116 283 y(Sc)o(hmidt)12 b(T)m(elescop)q(e.)-54
360 y(The)e(resulting)g(Digitized)g(Sky)g(Surv)o(ey)g(\(DSS\))g(whic)o
(h)g(co)o(v)o(ers)-116 410 y(the)g(en)o(tire)g(sky)g(is)f(generally)h
(a)o(v)n(ailable)d(as)j(a)f(set)i(of)e(102)g(CDR)o(OM)-116
460 y(disks)14 b(and)g(constitutes)i(an)e(extremely)g(v)n(aluable)f
(astronomical)-116 510 y(resource.)-54 587 y(The)h(co)q(ordinate)g
(system)f(asso)q(ciated)h(with)g(the)g(DSS)f(is)h(de-)-116
637 y(scrib)q(ed)g(in)f(the)g(b)q(o)q(oklets)g(pro)o(vided)g(with)g
(the)h(CDR)o(OM)e(set.)i(It)-116 687 y(is)g(established)h(b)o(y)f(a)g
(set)i(of)d(co)q(e\016cien)o(ts)j(whic)o(h)e(de\014ne)i(a)e(p)q(oly-)
-116 737 y(nomial)h(plate)k(solution.)e(The)i(co)q(e\016cien)o(ts)g
(are)g(enco)q(ded)h(in)e(a)-116 786 y(set)e(of)f(FITS)g(header)h(cards)
g(and)g(sp)q(ecial)f(purp)q(ose)i(soft)o(w)o(are)e(is)-116
836 y(pro)o(vided)e(to)h(implemen)o(t)d(the)k(co)q(ordinate)f(system.)
-54 913 y(As)e(describ)q(ed)i(in)d(the)h(DSS)g(b)q(o)q(oklet,)f(the)i
(\014rst)f(step)h(in)e(com-)-116 963 y(puting)19 b(celestial)g(co)q
(ordinates)h(from)e(DSS)h(pixel)g(co)q(ordinates)-116
1013 y(\()p Fj(I)s(;)7 b(J)t Fk(\))12 b(is)h(to)f(compute)g(linear)g
(o\013sets)i(\()p Fj(X)q(;)7 b(Y)i Fk(\))k(measured)g(in)f(mm)-116
1063 y(from)g(the)i(plate)g(cen)o(tre)-116 1209 y Fj(X)24
b Fk(=)d(\()p Fj(X)45 1215 y Fi(c)72 1209 y Fh(\000)9
b Fj(p)134 1215 y Fi(x)155 1209 y Fj(I)s Fk(\))p Fj(=)p
Fk(1000)p Fj(;)561 b Fk(\(1\))-112 1271 y Fj(Y)30 b Fk(=)21
b(\()p Fj(p)32 1277 y Fi(y)52 1271 y Fj(J)13 b Fh(\000)d
Fj(Y)154 1277 y Fi(c)171 1271 y Fk(\))p Fj(=)p Fk(1000)p
Fj(;)566 b Fk(\(2\))-116 1417 y(where)12 b(\()p Fj(X)51
1423 y Fi(c)68 1417 y Fj(;)7 b(Y)111 1423 y Fi(c)128
1417 y Fk(\))k(are)g(the)h(plate)e(cen)o(tre)j(co)q(ordinates)f(in)e
Fj(\026)p Fk(m,)f(and)-116 1467 y(\()p Fj(p)-79 1473
y Fi(x)-59 1467 y Fj(;)e(p)-19 1473 y Fi(y)1 1467 y Fk(\))18
b(are)h(the)g Fj(x)p Fk(-,)f(and)g Fj(y)q Fk(-dimensions)g(of)g(a)g
(pixel,)g(in)g Fj(\026)p Fk(m.)-116 1517 y(Standard)c(co)q(ordinates)g
(are)g(computed)g(via)-114 1663 y Fj(\030)22 b Fk(=)f
Fj(a)1 1669 y Fg(1)20 1663 y Fj(X)13 b Fk(+)c Fj(a)130
1669 y Fg(2)149 1663 y Fj(Y)19 b Fk(+)9 b Fj(a)255 1669
y Fg(3)283 1663 y Fk(+)g Fj(a)346 1669 y Fg(4)365 1663
y Fj(X)402 1646 y Fg(2)430 1663 y Fk(+)h Fj(a)494 1669
y Fg(5)512 1663 y Fj(X)s(Y)20 b Fk(+)9 b Fj(a)656 1669
y Fg(6)675 1663 y Fj(Y)708 1646 y Fg(2)736 1663 y Fk(+)-21
1725 y Fj(a)1 1731 y Fg(7)27 1691 y Ff(\000)46 1725 y
Fj(X)83 1708 y Fg(2)111 1725 y Fk(+)h Fj(Y)186 1708 y
Fg(2)205 1691 y Ff(\001)233 1725 y Fk(+)g Fj(a)297 1731
y Fg(8)315 1725 y Fj(X)352 1708 y Fg(3)381 1725 y Fk(+)f
Fj(a)444 1731 y Fg(9)463 1725 y Fj(X)500 1708 y Fg(2)519
1725 y Fj(Y)19 b Fk(+)9 b Fj(a)625 1731 y Fg(10)660 1725
y Fj(X)s(Y)731 1708 y Fg(2)759 1725 y Fk(+)-21 1801 y
Fj(a)1 1807 y Fg(11)37 1801 y Fj(Y)70 1783 y Fg(3)98
1801 y Fk(+)g Fj(a)161 1807 y Fg(12)196 1801 y Fj(X)241
1767 y Ff(\000)260 1801 y Fj(X)297 1783 y Fg(2)325 1801
y Fk(+)h Fj(Y)400 1783 y Fg(2)419 1767 y Ff(\001)447
1801 y Fk(+)g Fj(a)511 1807 y Fg(13)546 1801 y Fj(X)590
1767 y Ff(\000)609 1801 y Fj(X)646 1783 y Fg(2)675 1801
y Fk(+)f Fj(Y)750 1783 y Fg(2)768 1767 y Ff(\001)787
1775 y Fg(2)813 1801 y Fj(;)45 b Fk(\(3\))-116 1868 y
Fj(\021)21 b Fk(=)g Fj(b)-3 1874 y Fg(1)16 1868 y Fj(Y)d
Fk(+)10 b Fj(b)118 1874 y Fg(2)136 1868 y Fj(X)j Fk(+)d
Fj(b)243 1874 y Fg(3)270 1868 y Fk(+)g Fj(b)330 1874
y Fg(4)348 1868 y Fj(Y)382 1850 y Fg(2)410 1868 y Fk(+)f
Fj(b)469 1874 y Fg(5)488 1868 y Fj(X)s(Y)19 b Fk(+)9
b Fj(b)627 1874 y Fg(6)646 1868 y Fj(X)683 1850 y Fg(2)711
1868 y Fk(+)-21 1930 y Fj(b)-3 1936 y Fg(7)23 1896 y
Ff(\000)42 1930 y Fj(X)79 1913 y Fg(2)107 1930 y Fk(+)h
Fj(Y)182 1913 y Fg(2)201 1896 y Ff(\001)229 1930 y Fk(+)g
Fj(b)289 1936 y Fg(8)307 1930 y Fj(Y)340 1913 y Fg(3)368
1930 y Fk(+)g Fj(b)428 1936 y Fg(9)446 1930 y Fj(X)s(Y)517
1913 y Fg(2)545 1930 y Fk(+)f Fj(b)604 1936 y Fg(10)639
1930 y Fj(X)676 1913 y Fg(2)696 1930 y Fj(Y)18 b Fk(+)-21
2005 y Fj(b)-3 2011 y Fg(11)32 2005 y Fj(X)69 1988 y
Fg(3)98 2005 y Fk(+)9 b Fj(b)157 2011 y Fg(12)192 2005
y Fj(Y)233 1972 y Ff(\000)252 2005 y Fj(X)289 1988 y
Fg(2)317 2005 y Fk(+)h Fj(Y)392 1988 y Fg(2)411 1972
y Ff(\001)439 2005 y Fk(+)f Fj(b)498 2011 y Fg(13)533
2005 y Fj(Y)574 1972 y Ff(\000)593 2005 y Fj(X)630 1988
y Fg(2)658 2005 y Fk(+)h Fj(Y)733 1988 y Fg(2)752 1972
y Ff(\001)771 1980 y Fg(2)796 2005 y Fj(;)62 b Fk(\(4\))-116
2151 y(and)19 b(the)h(J2000)e(righ)o(t)h(ascension)h(and)f(declination)
g(are)g(then)-116 2201 y(giv)o(en)13 b(b)o(y)-116 2347
y Fj(\013)20 b Fk(=)h(tan)44 2330 y Fe(\000)p Fg(1)96
2347 y Fk([)o(\()p Fj(\030)r(=)7 b Fk(cos)g Fj(\016)251
2353 y Fi(c)269 2347 y Fk(\))g Fj(=)g Fk(\(1)i Fh(\000)g
Fj(\021)f Fk(tan)f Fj(\016)521 2353 y Fi(c)538 2347 y
Fk(\))q(])h(+)i Fj(\013)644 2353 y Fi(c)660 2347 y Fj(;)198
b Fk(\(5\))-110 2410 y Fj(\016)23 b Fk(=)e(tan)44 2392
y Fe(\000)p Fg(1)89 2410 y Fh(f)p Fk([)o(\()p Fj(\021)10
b Fk(+)g(tan)d Fj(\016)295 2416 y Fi(c)312 2410 y Fk(\))g(cos)h(\()p
Fj(\013)h Fh(\000)g Fj(\013)518 2416 y Fi(c)535 2410
y Fk(\)])d Fj(=)h Fk([1)h Fh(\000)i Fj(\021)e Fk(tan)f
Fj(\016)794 2416 y Fi(c)811 2410 y Fk(])p Fh(g)p Fj(;)14
b Fk(\(6\))-116 2556 y(where)f(\()p Fj(\013)45 2562 y
Fi(c)62 2556 y Fj(;)7 b(\016)99 2562 y Fi(c)116 2556
y Fk(\))12 b(are)h(the)g(plate)f(cen)o(tre)i(J2000.0)d(righ)o(t)h
(ascension)-116 2605 y(and)e(declination.)g(These)j(co)q(e\016cien)o
(ts)f(are)f(enco)q(ded)i(in)d(the)i(DSS)-116 2655 y(FITS)i(header)g
(via)f(the)i(follo)o(wing)c(k)o(eyw)o(ords)1130 -99 y
Fj(X)1164 -93 y Fi(c)1237 -99 y Fd(PP03)1130 -50 y Fj(Y)1154
-44 y Fi(c)1237 -50 y Fd(PP06)1130 0 y Fj(p)1151 6 y
Fi(x)1237 0 y Fd(XPIXELSZ)1130 50 y Fj(p)1151 56 y Fi(y)1237
50 y Fd(YPIXELSZ)1130 100 y Fj(a)1152 106 y Fg(1)1237
100 y Fd(AMDX1)1130 144 y Fk(.)1130 161 y(.)1130 177
y(.)1237 144 y(.)1237 161 y(.)1237 177 y(.)1130 227 y
Fj(a)1152 233 y Fg(13)1237 227 y Fd(AMDX13)1130 277 y
Fj(b)1148 283 y Fg(1)1237 277 y Fd(AMDY1)1130 321 y Fk(.)1130
338 y(.)1130 354 y(.)1237 321 y(.)1237 338 y(.)1237 354
y(.)1130 404 y Fj(b)1148 410 y Fg(13)1237 404 y Fd(AMDY13)1130
454 y Fj(\013)1157 460 y Fi(c)1237 454 y Fd(PLTRAH,)20
b(PLTRAM,)g(PLTRAS)1130 504 y Fj(\016)1148 510 y Fi(c)1237
504 y Fd(PLTDECSN,)g(PLTDECD,)g(PLTDECM,)1237 554 y(PLTDECS)1032
647 y Fk(In)k(translating)f(the)h(DSS)g(co)q(ordinate)g(system)f(in)o
(to)g(the)970 697 y(presen)o(t)f(formalism)17 b(w)o(e)k(\014rst)g(note)
g(that)g(the)g(DSS)f(transfor-)970 747 y(mation)11 b(is)i(de\014ned)h
(as)f(a)g(depro)r(jection.)g(That)g(is,)g(the)g(prescrip-)970
796 y(tion)e(giv)o(en)h(is)f(that)h(for)g(computing)e(celestial)i(co)q
(ordinates)g(from)970 846 y(Cartesian)i(co)q(ordinates)h(in)e(the)i
(plane)e(of)g(pro)r(jection.)h(Compu-)970 896 y(tation)d(of)h(the)g
(forw)o(ard)f(pro)r(jection)i(requires)g(iterativ)o(e)e(solution)970
946 y(of)i(the)i(p)q(olynomial)10 b(equations)k(3)g(and)g(4.)1032
997 y(The)19 b(DSS)f(pixel)g(co)q(ordinates)h(\()p Fj(I)s(;)7
b(J)t Fk(\))19 b(are)g(measured)f(with)970 1047 y(resp)q(ect)g(to)d
(the)g Fc(b)n(ottom)h(left-hand)g(c)n(orner)f Fk(of)g(a)g(pixel)f
(whereas)970 1097 y(the)k(\()p Fj(i;)7 b(j)r Fk(\))18
b(pixel)f(co)q(ordinates)h(used)h(here)f(are)g(measured)g(with)970
1146 y(resp)q(ect)c(to)d(the)h Fc(c)n(entr)n(e)f Fk(of)f(a)h(pixel.)g
(Also,)f(the)i(b)q(ottom)e(left-hand)970 1196 y(corner)i(of)e(the)i
(\014rst)g(pixel)e(in)g(a)h(DSS)f(subimage)g(has)h(co)q(ordinates)970
1246 y(de\014ned)17 b(b)o(y)e(the)h Fd(CNPIX1)e Fk(and)h
Fd(CNPIX2)f Fk(header)i(cards)g(whereas)970 1296 y(the)g(\()p
Fj(i;)7 b(j)r Fk(\))16 b(pixel)f(co)q(ordinates)h(of)f(the)h(cen)o(tre)
h(of)e(the)h(\014rst)g(pixel)970 1346 y(are)e(alw)o(a)o(ys)f(\(1)p
Fj(;)7 b Fk(1\).)13 b(Hence)976 1440 y Fj(I)24 b Fk(=)d
Fj(i)10 b Fk(+)f(\()p Fd(CNPIX1)f Fh(\000)i Fk(0)p Fj(:)p
Fk(5\))c Fj(;)535 b Fk(\(7\))970 1502 y Fj(J)25 b Fk(=)c
Fj(j)12 b Fk(+)d(\()p Fd(CNPIX2)f Fh(\000)i Fk(0)p Fj(:)p
Fk(5\))c Fj(:)530 b Fk(\(8\))1032 1597 y(Substituting)12
b(Eqs.)g(7)f(and)h(8)f(in)o(to)g(1)g(and)h(2)f(to)h(\014nd)g(the)g(\()p
Fj(i;)7 b(j)r Fk(\))970 1647 y(co)q(ordinates)17 b(whic)o(h)f(corresp)q
(ond)h(to)f(\()p Fj(X)q(;)7 b(Y)i Fk(\))16 b(=)f(\(0)p
Fj(;)7 b Fk(0\))15 b(w)o(e)h(ma)o(y)970 1697 y(write)970
1791 y Fd(CRPIX1)k Fk(=)h Fj(x)1199 1797 y Fi(c)1215
1791 y Fj(=p)1257 1797 y Fi(x)1287 1791 y Fh(\000)10
b Fk(\()p Fd(CNPIX1)e Fh(\000)h Fk(0)p Fj(:)p Fk(5\))d
Fj(;)343 b Fk(\(9\))970 1853 y Fd(CRPIX2)20 b Fk(=)h
Fj(y)1195 1859 y Fi(c)1212 1853 y Fj(=p)1254 1859 y Fi(y)1283
1853 y Fh(\000)9 b Fk(\()p Fd(CNPIX2)f Fh(\000)i Fk(0)p
Fj(:)p Fk(5\))c Fj(:)326 b Fk(\(10\))1032 1948 y(The)13
b(co)q(ordinate)f(incremen)o(ts)g(giv)o(en)g(b)o(y)g
Fj(p)1709 1954 y Fi(x)1741 1948 y Fk(and)g Fj(p)1841
1954 y Fi(y)1873 1948 y Fk(in)f(units)970 1998 y(of)18
b(mm/pixel)e(ma)o(y)h(b)q(e)i(con)o(v)o(erted)h(to)f(the)g(required)h
(units)f(of)970 2048 y(degree/pixel)11 b(b)o(y)g(ev)n(aluating)e
Fj(@)r(\030)r(=@)r(X)14 b Fk(and)d Fj(@)r(\021)q(=@)r(Y)20
b Fk(at)10 b(the)i(plate)970 2098 y(cen)o(tre)k(to)d(\014nd)h(the)h
(appropriate)f(scaling)f(factors,)h(whence)970 2192 y
Fd(CDELT1)20 b Fk(=)h Fh(\000)p Fj(a)1229 2198 y Fg(1)1248
2192 y Fj(p)1269 2198 y Fi(x)1289 2192 y Fj(=)p Fk(3600000)p
Fj(;)467 b Fk(\(11\))970 2254 y Fd(CDELT2)20 b Fk(=)h
Fj(b)1193 2260 y Fg(1)1211 2254 y Fj(p)1232 2260 y Fi(y)1252
2254 y Fj(=)p Fk(3600000)p Fj(:)504 b Fk(\(12\))1032
2350 y(F)m(rom)19 b(Eqs.)i(5)f(and)h(6)f(it)h(can)f(b)q(e)i(sho)o(wn)e
(that)h(the)g(stan-)970 2399 y(dard)15 b(co)q(ordinates,)h(\()p
Fj(\030)r(;)7 b(\021)q Fk(\),)14 b(are)i(Cartesian)f(co)q(ordinates)h
(in)f(the)970 2449 y(plane)10 b(of)f(a)h(gnomonic)d(pro)r(jection)k
(with)e(tangen)o(t)h(p)q(oin)o(t)f(\()p Fj(\013)1911
2455 y Fi(c)1928 2449 y Fj(;)e(\016)1965 2455 y Fi(c)1982
2449 y Fk(\).)970 2499 y(Hence)16 b(w)o(e)e(m)o(ust)f(mak)o(e)f(the)i
(asso)q(ciation)970 2593 y Fd(CRVAL1)20 b Fk(=)h Fj(\013)1202
2599 y Fi(c)1218 2593 y Fj(;)706 b Fk(\(13\))970 2655
y Fd(CRVAL2)20 b Fk(=)h Fj(\016)1193 2661 y Fi(c)1210
2655 y Fj(:)714 b Fk(\(14\))p eop
%%Page: 2 2
2 1 bop 937 -192 a Fl(2)-116 -93 y Fk(Ho)o(w)o(ev)o(er,)12
b(in)g(this)h(regard,)f(w)o(e)h(note)g(that)f(there)i(is)f(an)f
(inconsis-)-116 -43 y(tency)i(in)e(what)h(the)h(DSS)f(form)o(ulation)d
(refers)k(to)f(as)h(the)f(\\plate)-116 7 y(cen)o(ter".)d(Eqs.)h(5)e
(and)h(6)g(giv)o(e)f(\()p Fj(\013;)e(\016)r Fk(\))k(=)h(\()p
Fj(\013)539 13 y Fi(c)556 7 y Fj(;)7 b(\016)593 13 y
Fi(c)609 7 y Fk(\))k(at)e(\()p Fj(\030)r(;)e(\021)q Fk(\))12
b(=)g(\(0)p Fj(;)7 b Fk(0\))-116 57 y(but)25 b(from)e(Eqs.)j(3)f(and)g
(4)g(w)o(e)g(ha)o(v)o(e)g(\()p Fj(\030)r(;)7 b(\021)q
Fk(\))30 b(=)h(\()p Fj(a)771 63 y Fg(3)790 57 y Fj(;)7
b(b)827 63 y Fg(3)845 57 y Fk(\))25 b(at)-116 106 y(\()p
Fj(X)q(;)7 b(Y)i Fk(\))22 b(=)g(\(0)p Fj(;)7 b Fk(0\).)18
b(The)j(o\013sets)g(\()p Fj(a)464 112 y Fg(3)483 106
y Fj(;)7 b(b)520 112 y Fg(3)537 106 y Fk(\))21 b(v)n(ary)e(from)f
(plate)i(to)-116 156 y(plate)13 b(but)h(are)g(t)o(ypically)f(ab)q(out)g
(1)h(arcsec)h(in)e(magnitude.)f(This)-116 206 y(should)g(not)g(in)o
(tro)q(duce)i(an)e(error)i(pro)o(vided)e(that)h(a)f(full)f(compu-)-116
256 y(tation)i(of)g(co)q(ordinates)i(is)e(done.)-54 306
y(The)j(\()p Fj(x;)7 b(y)q Fk(\))16 b(co)q(ordinates)g(obtained)g(from)
e(the)i(ab)q(o)o(v)o(e)g(stan-)-116 356 y(dard)j(header)g(cards)h(will)
d(b)q(e)j(in)e(units)h(of)g(degrees)h(and)f(m)o(ust)-116
405 y(b)q(e)f(con)o(v)o(erted)h(to)f(\()p Fj(X)q(;)7
b(Y)i Fk(\))18 b(in)f(mm)e(b)q(efore)k(applying)e(the)h(DSS)-116
455 y(p)q(olynomial)10 b(form)o(ulae)i(of)h(Eqs.)h(3)g(and)f(4)-116
546 y Fj(X)24 b Fk(=)d(3600)p Fj(=a)122 552 y Fg(1)139
546 y Fj(x;)674 b Fk(\(15\))-112 609 y Fj(Y)30 b Fk(=)21
b(3600)p Fj(=b)118 615 y Fg(1)135 609 y Fj(y)q(:)681
b Fk(\(16\))-116 700 y(Once)15 b(\()p Fj(X)q(;)7 b(Y)i
Fk(\))15 b(ha)o(v)o(e)f(b)q(een)h(obtained)f(and)g(\()p
Fj(\030)r(;)7 b(\021)q Fk(\))14 b(computed)g(via)-116
750 y(Eqs.)d(3)g(and)g(4)g(the)h(nativ)o(e)f(spherical)g(co)q
(ordinates)h(ma)o(y)d(b)q(e)j(com-)-116 800 y(puted)i(as)g(an)g(in)o(v)
o(erse)g(gnomonic)e(pro)r(jection)-116 891 y Fj(\036)20
b Fk(=)h(arg)7 b(\()q Fh(\000)p Fj(\021)q(;)g(\030)r
Fk(\))f Fj(;)658 b Fk(\(17\))-112 966 y Fj(\022)22 b
Fk(=)f(tan)42 949 y Fe(\000)p Fg(1)94 920 y Ff(h)113
966 y Fk(\(648000)p Fj(=\031)q Fk(\))p Fj(=)338 927 y
Ff(p)p 378 927 131 2 v 378 966 a Fj(\030)398 954 y Fg(2)426
966 y Fk(+)10 b Fj(\021)490 954 y Fg(2)508 920 y Ff(i)535
966 y Fj(:)302 b Fk(\(18\))-116 1067 y(The)14 b(equations)g(for)f(the)i
(forw)o(ard)e(gnomonic)f(pro)r(jection)i(are)-114 1159
y Fj(\030)22 b Fk(=)f(\(648000)p Fj(=\031)q Fk(\))7 b(sin)f
Fj(\036)h Fk(cot)g Fj(\022)q(;)476 b Fk(\(19\))-116 1221
y Fj(\021)21 b Fk(=)g Fh(\000)p Fk(\(648000)p Fj(=\031)q
Fk(\))7 b(cos)g Fj(\036)g Fk(cot)g Fj(\022)q(:)439 b
Fk(\(20\))-54 1312 y(The)14 b(remainder)g(of)g(the)g(translation)g
(consists)h(of)f(assigning)-116 1362 y(the)g(DSS)g(p)q(olynomial)c(co)q
(e\016cien)o(ts)15 b(to)f(the)h Fd(PROJP)p Fc(n)e Fk(as)h(follo)o(ws)
155 1451 y Fd(PROJP1)70 b Fj(a)379 1457 y Fg(1)464 1451
y Fk(\()p Fd(AMDX1)p Fk(\))155 1495 y(.)155 1511 y(.)155
1528 y(.)357 1495 y(.)357 1511 y(.)357 1528 y(.)464 1495
y(.)464 1511 y(.)464 1528 y(.)155 1578 y Fd(PROJP13)48
b Fj(a)379 1584 y Fg(13)464 1578 y Fk(\()p Fd(AMDX13)p
Fk(\))155 1628 y Fd(PROJP21)g Fj(b)375 1634 y Fg(1)464
1628 y Fk(\()p Fd(AMDY1)p Fk(\))155 1672 y(.)155 1688
y(.)155 1705 y(.)357 1672 y(.)357 1688 y(.)357 1705 y(.)464
1672 y(.)464 1688 y(.)464 1705 y(.)155 1755 y Fd(PROJP33)g
Fj(b)375 1761 y Fg(13)464 1755 y Fk(\()p Fd(AMDY13)p
Fk(\))-116 1844 y(The)11 b Fd(RADECSYS)e Fk(card)i(should)f(also)g(b)q
(e)h(sp)q(eci\014ed)i(as)d(\\)p Fd(FK5)p Fk(",)f(with)-116
1894 y(the)14 b Fd(EQUINOX)e Fk(card)j(set)g(to)e Fd(2000.0)p
Fk(.)-116 2602 y Fl(This)e(article)i(w)o(as)d(pro)q(cessed)j(b)o(y)e
(the)g(author)h(using)g(Springer-V)m(erlag)-116 2647
y(L)-106 2639 y Fb(A)-89 2647 y Fl(T)-67 2655 y(E)-47
2647 y(X)h(A&A)f(st)o(yle)i(\014le)g Fa(L-AA)d Fl(v)o(ersion)k(3.)p
eop
%%Trailer
end
userdict /end-hook known{end-hook}if
%%EOF