updateVariance¶
- lsst.ip.isr.updateVariance(maskedImage, gain, readNoise, replace=True)¶
Set the variance plane based on the image plane.
The maskedImage must have units of
adu(if gain != 1.0) or electron (if gain == 1.0). This routine will always produce a variance plane in the same units as the image.- Parameters:
- maskedImage
lsst.afw.image.MaskedImage Image to process. The variance plane is modified.
- gainscalar
The amplifier gain in electron/adu.
- readNoisescalar
The amplifier read noise in electron/pixel.
- replace
bool, optional Replace the current variance? If False, the image variance will be added to the current variance plane.
- maskedImage