Photometric redshifts can be routinely obtained to accuracies of better than 0.1 in \Delta z/ ( 1+z ) .
However , the issue of dust extinction is one that has still not been well quantified .
In this paper the success of two template-fitting photometric redshift codes ( I MP Z and HYPERZ ) at reliably returning A _ { V } in addition to redshift is explored .
New data on the CNOC2 spectroscopic sample of 0.2 < z < 0.7 galaxies are presented .
These data allow us to estimate A _ { V } values from the observed Balmer decrements .
We also investigate whether the empirical value of \gamma = 0.44 , the ratio between gas- and star- derived extinction , as determined by ( ) , is necessarily the best value for this sample .

When comparing the two codes to the Balmer-derived A _ { V } , a correlation between the photometrically derived A _ { V } , Phot-A _ { V } , and the Balmer-A _ { V } is found .
The correlation is improved when the empirical value of \gamma = 0.44 is allowed to vary .
From least-squares-fitting the minimum in the reduced \chi ^ { 2 } distribution is found for \gamma \sim 0.25 \pm 0.2 .
For the sample of galaxies here , the factor of two difference in covering factor implied by the Calzetti ratio is found to be plausible .
The CNOC2 galaxies with detected Balmer lines have some preference for an increased covering factor difference , which would perhaps imply they are undergoing more rapid , ‘ bursty ’ star formation than the galaxies Calzetti used in her derivation .