derive the probability of a $z<5$ source to be 15%. @Dunlop instead adopt marginal detections of the source in the $Viz$ bandpasses which we discuss in Secion 3.2. Any significant detection of the galaxy at optical wavelengths would rule out a photometric redshift solution which favors $z>6$. @Dunlop find a minimum in the $\chi^{2}$ distribution at $z\sim2.2$.

The detection of HUDF-JD2 in the deep GOODS 24$\mu$m images did not break the degeneracy. @Mobasher suggests the hot dust emission is from an obscured AGN in the galaxy. Alternately, the 24[$\mu$m]{} emission could be dominated from polycyclic aromatic hydrocarbon (PAH) features which would be present if the object is an extremely red, dusty starburst galaxy at $z\sim2.5$ [@Yan:04; @Stern:06]. Inclusion of the 16 and 22[$\mu$m]{} data allows us to measure a photometric redshift from the mid-infrared which could potentially break this degeneracy, independent of the optical/near-infrared SED fits. Although fitting optical to mid-infrared simultaneously is more elegant, it is virtually impossible since there is virtually no correlation between optical/near-infrared SEDs and mid-infrared SEDs of galaxies.

Mid-Infrared Photometric Redshifts
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The mid-infrared SED of a star-forming galaxy is a complicated interplay of warm dust continuum, PAH emission and silicate absorption features. The ratio 