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Some JSA tiles considered by astoverlap to be identical #21

Closed grahambell closed 10 years ago

grahambell commented 10 years ago

If the regions output by TILEINFO for the tiles at the southern corners of facets 6 and 4 (the equatorial facets at RA 12 and 0) are given to ASTOVERLAP, it considers them to be identical:

$ tileinfo instrument="SCUBA-2(850)" itile=24576 region=24576.ast
$ tileinfo instrument="SCUBA-2(850)" itile=16384 region=16384.ast
$ astoverlap 24576.ast 16384.ast

The Regions are identical to within their uncertainties.

Maybe it's not looking at the different reference position for tile 6? Because this is one of the differences between the region files:

$ diff -U0 24576.ast 16384.ast
[...]
@@ -77 +77 @@
-                SRef1 = 3.14159265358979   # Ref. pos. RA 12:00:00.0
+                SRef1 = 0  # Ref. pos. RA 0:00:00.0
[...]

The same is true for some other pairs such as 24579 and 16387.

grahambell commented 10 years ago

It looks like this might have been fixed by the abfacf01495dcaad3b3b03ad0fd4c1a28e3835be commit.