An imaging device comprising: a signal processor configured to perform a first signal processing to temporarily store a series of continuously acquired first image data in buffer memory (51, 52) at a first rate in response to a user pressing a first release button, the first image data comprising a plurality of pieces of picture data, to read out the first image data from the buffer memory (51, 52), and to perform a second signal processing on the first image data at a second rate which is slower than the first rate to generate second image data, the second image data comprising a plurality of pieces of picture data, to store the second image data in the buffer memory (51, 52); and to perform a third signal processing to read out the second image data from the buffer memory (51, 52) for recording, by a recording unit, on a recording medium; and a controller configured to determine that a remaining storage capacity of the buffer memory (51, 52) is less than a predetermined amount and to detect that the user has pressed the first release button whilst simultaneously pressing a second forced return button to indicate a return to continuous acquisition, the second forced release button being separate and distinct from the first release button, and in response to determining that the remaining storage capacity of the buffer memory (51, 52) is less than a predetermined amount whilst detecting that the user has indicated the return to continuous acquisition, to delete one or more pieces of picture data of both of the first image data and the second image data stored in the buffer memory (51, 52) in response to the user operation indicating the return to continuous operation, which is performed while the second image data is recorded on the recording medium and is performed while unprocessed first image data is left in the buffer memory (51, 52) and before image data corresponding to all of the second image data stored in the buffer memory (51, 52) has been recorded on the recording medium. a signal processor configured to perform a first signal processing to temporarily store a series of continuously acquired first image data in buffer memory (51, 52) at a first rate in response to a user pressing a first release button, the first image data comprising a plurality of pieces of picture data, to read out the first image data from the buffer memory (51, 52), and to perform a second signal processing on the first image data at a second rate which is slower than the first rate to generate second image data, the second image data comprising a plurality of pieces of picture data, to store the second image data in the buffer memory (51, 52); and to perform a third signal processing to read out the second image data from the buffer memory (51, 52) for recording, by a recording unit, on a recording medium; and a controller configured to determine that a remaining storage capacity of the buffer memory (51, 52) is less than a predetermined amount and to detect that the user has pressed the first release button whilst simultaneously pressing a second forced return button to indicate a return to continuous acquisition, the second forced release button being separate and distinct from the first release button, and in response to determining that the remaining storage capacity of the buffer memory (51, 52) is less than a predetermined amount whilst detecting that the user has indicated the return to continuous acquisition, to delete one or more pieces of picture data of both of the first image data and the second image data stored in the buffer memory (51, 52) in response to the user operation indicating the return to continuous operation, which is performed while the second image data is recorded on the recording medium and is performed while unprocessed first image data is left in the buffer memory (51, 52) and before image data corresponding to all of the second image data stored in the buffer memory (51, 52) has been recorded on the recording medium.