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We compare the rms contrast in observed speckle reconstructed G-band imageswith synthetic filtergrams computed from two magneto-hydrodynamic simulationsnapshots. The observations consist of 103 bursts of 80 frames each taken atthe Dunn Solar Telescope (DST), sampled at twice the diffraction limit of thetelescope. The speckle reconstructions account for the performance of theAdaptive Optics (AO) system at the DST to supply reliable photometry. We find aconsiderable discrepancy in the observed rms contrast of 14.1% for the bestreconstructed images, and the synthetic rms contrast of 21.5% in a simulationsnapshot thought to be representative of the quiet Sun. The areas of featuresin the synthetic filtergrams that have positive or negative contrast beyond theminimum and maximum values in the reconstructed images have spatial scales thatshould be resolved. This leads us to conclude that there are fundamentaldifferences in the rms G-band contrast between observed and computedfiltergrams. On the basis of the substantially reduced granular contrast of16.3% in the synthetic plage filtergram we speculate that the quiet-Sun maycontain more weak magnetic field than previously thought.

The discrepancy in G-band contrast: Where is the quiet Sun?