add radec_offsets (due to aberration compensation by FGS) to wcs projection

observation_sim/ObservationSim.py

@@ -92,16 +92,21 @@ class Observation(object):
                 input_time_str=time_str
             )
             ra_cen, dec_cen = ra_cen[0], dec_cen[0]
+            ra_offset, dec_offset = pointing.ra - ra_cen, pointing.dec - dec_cen
         else:
             ra_cen = pointing.ra
             dec_cen = pointing.dec
+            ra_offset, dec_offset = 0., 0.
 
         # Prepare necessary chip properties for simulation
         chip = self.prepare_chip_for_exposure(chip, ra_cen, dec_cen, pointing)
 
         # Initialize SimSteps
         sim_steps = SimSteps(overall_config=self.config,
-                             chip_output=chip_output, all_filters=self.all_filters)
+                             chip_output=chip_output,
+                             all_filters=self.all_filters,
+                             ra_offset=ra_offset,
+                             dec_offset=dec_offset)
 
         for step in pointing.obs_param["call_sequence"]:
             if self.config["run_option"]["out_cat_only"]:

observation_sim/mock_objects/MockObject.py

@@ -59,13 +59,13 @@ class MockObject(object):
         flux = self.getFluxFilter(filt)
         return flux * tel.pupil_area * exptime
 
-    def getPosWorld(self):
-        ra = self.param["ra"]
-        dec = self.param["dec"]
+    def getPosWorld(self, ra_offset=0., dec_offset=0.):
+        ra = self.param["ra"] + ra_offset
+        dec = self.param["dec"] + dec_offset
         return galsim.CelestialCoord(ra=ra * galsim.degrees, dec=dec * galsim.degrees)
 
-    def getPosImg_Offset_WCS(self, img, fdmodel=None, chip=None, verbose=True, chip_wcs=None, img_header=None):
-        self.posImg = img.wcs.toImage(self.getPosWorld())
+    def getPosImg_Offset_WCS(self, img, fdmodel=None, chip=None, verbose=True, chip_wcs=None, img_header=None, ra_offset=0., dec_offset=0.):
+        self.posImg = img.wcs.toImage(self.getPosWorld(ra_offset, dec_offset))
         self.localWCS = img.wcs.local(self.posImg)
         # Apply field distortion model
         if (fdmodel is not None) and (chip is not None):

observation_sim/sim_steps/__init__.py

 import os
 
+
 class SimSteps:
-    def __init__(self, overall_config, chip_output, all_filters):
+    def __init__(self, overall_config, chip_output, all_filters, ra_offset=0., dec_offset=0.):
         self.overall_config = overall_config
         self.chip_output = chip_output
         self.all_filters = all_filters
+        self.ra_offset = ra_offset
+        self.dec_offset = dec_offset
 
     from .prepare_headers import prepare_headers, updateHeaderInfo
     from .add_sky_background import add_sky_background_sci, add_sky_flat_calibration, add_sky_background
@@ -15,6 +18,7 @@ class SimSteps:
     from .readout_output import add_prescan_overscan, add_readout_noise, apply_gain, quantization_and_output
     from .add_LED_flat import add_LED_Flat
 
+
 SIM_STEP_TYPES = {
     "scie_obs": "add_objects",
     "sky_background": "add_sky_background",
@@ -31,6 +35,6 @@ SIM_STEP_TYPES = {
     "readout_noise": "add_readout_noise",
     "gain": "apply_gain",
     "quantization_and_output": "quantization_and_output",
-    "led_calib_model":"add_LED_Flat",
-    "sky_flatField":"add_sky_flat_calibration",
+    "led_calib_model": "add_LED_Flat",
+    "sky_flatField": "add_sky_flat_calibration",
 }

observation_sim/sim_steps/add_objects.py

@@ -145,7 +145,7 @@ def add_objects(self, chip, filt, tel, pointing, catalog, obs_param):
 
         # Get position of object on the focal plane
         pos_img, _, _, _, fd_shear = obj.getPosImg_Offset_WCS(
-            img=chip.img, fdmodel=fd_model, chip=chip, verbose=False, chip_wcs=chip_wcs, img_header=self.h_ext)
+            img=chip.img, fdmodel=fd_model, chip=chip, verbose=False, chip_wcs=chip_wcs, img_header=self.h_ext, ra_offset=self.ra_offset, dec_offset=self.dec_offset)
 
         # [TODO] For now, only consider objects which their centers (after field distortion) are projected within the focal plane
         # Otherwise they will be considered missed objects