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imshift

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Shift the reference pixel of a CASA image header by a specified angle in RA/Dec. See also normallizeImage, scaleImage, and imageRegister.

Usage: 

au.imshift(img, rashift, decshift, copyimage=True, absolute=False)
  • rashift: value in arcsec to subtract from CRPIX1
  • decshift: value in arcsec to subtract from CRPIX2
  • copyimage: if True, then first copy the image to *.imshift (to avoid changing the original)
  • absolute: if True, then treat rashift and decshift as absolute degrees; or, if they are strings, then treat as HH:MM:SS.S and DD:MM:SS.S

Example: 

CASA <2>: au.imshift('hpacs_3HPPPPB_273.57_-17.50_v1.0_1396014183448.image',+1.29,-2.75)
Copied image to  hpacs_3HPPPPB_273.57_-17.50_v1.0_1396014183448.image.imshift           
Shifting RA  by +1.290000 arcsec = -0.645000 pixels                                     
Shifting Dec by -2.750000 arcsec = -1.375000 pixels

-- ToddHunter - 2014-06-07
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Topic revision: r4 - 2015-04-13, CrystalBrogan
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