The present invention relates to a method for exposing a photosensitive imaging sheet using a low temperature exposure step. The method includes the steps of:providing an imaging sheet including a substrate having provided on one of its surfaces a layer of microcapsules, said microcapsules containing an image-forming agent and a photohardenable composition comprising a free radical addition polymerizable or cross-linkable compound and a photoinitiator, said photoinitiator being capable of absorbing actinic radiation and producing free radicals which initiate free radical polymerization or cross-linking of said polymerizable or cross-linkable compound;cooling said imaging sheet to a temperature below ambient temperature; andimage-wise exposing said imaging sheet to actinic radiation while said imaging sheet is at said below ambient temperature.