JPL SIRTF Science Talks Tutorial Speaker Peter Eisenhardt (JPL ) Title SIRTF (Observing ) Proposal

Hires: Super-resolution for the Spitzer Space TelescopeCharles BackusVelu VelusamyTim ThompsonJohn ArballoDescription of hires algorithmSome hires tactical considerationsExamples of hires resultsCharles.Backus@jpl.nasa.govOctober, 2004 ADASS XIV O1.3 1Why Yet Another Deconvolution Program?Spitzer provides good SNR, critically sampled, with relativelysmall telescope, 85cm.Observation strategies provide redundant coverage.Goal: Pool the information from redundant coverage, increase resolution.Requirements:- Statistically appropriate use of redundant coverage- Photometric accuracy- Speed- Large data quantities mandate a fast program- Distortion management- Required by Spitzer optics - Ease of use- Turnkey program run in batch modeOctober, 2004 ADASS XIV O1.3 2Hires: Richardson-Lucy Algorithm for Redundant CoverageSingle coverageD acquired image D~n n−1 P assumed PSF, * is convolution~~f = f ∗PP(v)=P(−v)reflected psf, P n−1nf ∗Pfnth image estimate Redundant coverage- A simple extension using weighted averagingNimages D~j ~∗P  c (P *u )∑ jn−1∑ jk j jkf ∗Pj=1  jj,kn n−1   n−1f = f = f~ ~P *U P *u∑ ∑j j j jkj j,kAssume spatially invariant psf’s and uniform pixel noise.Linearities enable evaluation using twoconvolutions for each psf orientation.u same as data jkUse FFT’s for convolutions.pixels but set to 1.October, 2004 ADASS XIV O1.3 3Important Properties of hires ...