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Question: What are the current ACS/WFC aperture locations?

Reply:The ACS Instrument Handbook table 8.1 is updated below updated with the current WFC aperture parameters. Please especially note the updates for the WFC1-IRAMP and WFC2-ORAMP reference pixel and reference V2,V3 entries.


Table 8.1: WFC Aperture Parameters
Aperture Name
active area
Extent
(arcsec)
Reference
pixel
Reference
V2,V3
(arcsec)
x-axis angle
y-axis angle
(degrees from V3 through V2)
WFC
4096 × 4096
202 × 202
(2072,200)
on WFC1
(258,239)
92.2
177.5
WFC-FIX
4096 × 4096
202 × 202
(2072, 200)
(259,239)
92.2
177.5
WFCENTER
4096 × 4096
202 × 202
(2114, 2029)
(261,252)
92.1
177.5
WFC1
4096 × 2048
202 × 102
(2072, 1024)
(261,198)
92.5
177.3
WFC1-FIX
4096 × 2048
202 × 102
(2072, 1024)
(261,198)
92.5
177.3
WFC2
4096 × 2048
202 × 102
(2072, 1024)
(257,302)
91.7
177.8
WFC2-FIX
4096 × 2048
202 × 102
(2072, 1024)
(257,302)
91.7
177.8
WFC1-IRAMP
600 × 1500
45 × 85
(680,1325)
(194,187)
93.1
176.6
WFC1-MRAMP
600 × 1500
65 × 100
(3096,1024)
(312,196)
92.2
177.8
WFC2-MRAMP
600 × 150
65 × 100
(1048,1024)
(206,303)
91.9
177.5
WFC2-ORAMP
600 × 1500
60 × 85
(3494,708)
(328,316)
91.4
178.2
WFC1-SMFL
1024 × 1024
72 × 72
(3096,1024)
(312,196)
92.2
177.8
WFC2-SMFL
1024 × 1024
72 × 72
(1048,1024)
(206,304)
91.9
177.5