In the 18th century the tracery had been replaced by metal fittings and the triforiums and fanlights had been walled up. A plastering of several centimetres was to hide any trace of decay or renovation.

To achieve this it had been necessary to chop off the capitals, curls and frames, which explains why this "brutal camouflage technique" was often abused, although there are some beautiful stucco ornaments. Plastering was masking. The plaster needed to be removed as swiftly as possible to reveal the more beautiful natural stone.

The objective was to restore the original medieval state, so registration was not necessary. The subsequent medieval alterations would be presented as a historic scenario, but the baroque chapter was deleted.

Thanks to a lucky coincidence several polychrome remainders could still be found on the walls of the choir. Only the figurative vaultal paintings of the axis chapel were impressive enough to be integrated.

Almost everyone is of the opinion that the plastered, partially whitewashed stone did not only correspond to the medieval taste but was also most appropriate for the baroque decoration. It is impossible to reconstruct the colours at a given moment in time because there are few colour remainders. The variety of guilds and brotherhoods, who all decorated their chapel and columns according to their own taste, makes it unlikely that the church’s interior was once uniformly painted. We do know for certain that the church was whitewashed at regular intervals during the baroque era.