At first I thought you were asking for a comparison of the California (CA) quarter which was produced last year and the District of Columbia (DC) quarter which has been proposed for 2009 but not yet authorized.
Upon further contemplation, I think you might be asking the difference between Deep Cameo (DCAM) and Cameo (CAM) on proof quarters. If that is the case, then the difference is that the CAM proofs have less contrast than the DCAM quarters. The contrast the level of difference between the frosted devices (the raised areas of the coin) and the depth of the mirrors in the fields (the background).
Comments
Upon further contemplation, I think you might be asking the difference between Deep Cameo (DCAM) and Cameo (CAM) on proof quarters. If that is the case, then the difference is that the CAM proofs have less contrast than the DCAM quarters. The contrast the level of difference between the frosted devices (the raised areas of the coin) and the depth of the mirrors in the fields (the background).
WH