Jitter functionality is incomplete

[josePhoenix]

In the documentation for WebbPSF.JWInstrument, we have

    jitter : string "gaussian" or None
        Type of jitter model to apply. Currently only convolution with a Gaussian kernel of specified
        width `jitter_sigma` is implemented. (default: None)
    jitter_sigma : float
        Width of the jitter kernel in arcseconds (default: 0.007 arcsec)

However, this test code shows no difference between a PSF with jitter enabled and a PSF with no jitter:

import webbpsf
nc = webbpsf.NIRCam()
nc.options['jitter'] = None
psf = nc.calcPSF(nlambda=3)

nc.options['jitter'] = 'gaussian'
psf_jitter = nc.calcPSF(nlambda=3)
webbpsf.display_PSF_difference(psf, psf_jitter)

I think this is because calcPSF is completely rewritten for JWInstrument and doesn't automatically get updates we make to poppy.Instrument. Refactoring that is something to tackle for v0.4.

[mperrin]

Does #47 fix this?

[josePhoenix]

Yes!

Achievement unlocked: we closed all the issues on a milestone.