We investigate the extent to which ultrapowers by normal measures on can be correct about powersets for . We consider two versions of this questions, the capturing property and the local capturing property . holds if there is an ultrapower by a normal measure on which correctly computes . is a weakening of which holds if every subset of is contained in some ultrapower by a normal measure on . After examining the basic properties of these two notions, we identify the exact consistency strength of . Building on results of Cummings, who determined the exact consistency strength of , and using a forcing due to Apter and Shelah, we show that can hold at the least measurable cardinal.

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