An imaging apparatus comprising: a common terminal; a photography mode setting unit capable of setting a certain photography mode from among a plurality of photography modes including a first photography mode and a second photography mode; and a function setting unit configured, when the photography mode setting unit sets the certain photography mode to the first photography mode, to achieve a first function using the common terminal, and to not achieve a second function, and configured, when the photography mode setting unit sets the certain photography mode to the second photography mode, to achieve the second function using the common terminal, and to not achieve the first function, wherein the first photography mode is a photography mode for a moving image, the second photography mode is a photography mode for a still image, characterized in that: when the photography mode setting unit sets the certain photography mode to the photography mode for the moving image, the function setting unit causes the common terminal to function as either of an input terminal inputting a synchronizing signal for the moving image, the synchronizing signal being for pairing a timing of photographing of a plurality of imaging apparatuses including the imaging apparatus, and an output terminal outputting a synchronizing signal for the moving image, the synchronizing signal being for pairing a timing of photographing of the plurality of imaging apparatuses including the imaging apparatus, to achieve the first function, and, when the photography mode setting unit sets the certain photography mode to the photography mode for the still image, the function setting unit causes the common terminal to function as a trigger signal output terminal to achieve the second function, wherein the trigger signal is for causing an electronic flash to emit light. a common terminal; a photography mode setting unit capable of setting a certain photography mode from among a plurality of photography modes including a first photography mode and a second photography mode; and a function setting unit configured, when the photography mode setting unit sets the certain photography mode to the first photography mode, to achieve a first function using the common terminal, and to not achieve a second function, and configured, when the photography mode setting unit sets the certain photography mode to the second photography mode, to achieve the second function using the common terminal, and to not achieve the first function, wherein the first photography mode is a photography mode for a moving image, the second photography mode is a photography mode for a still image, characterized in that: when the photography mode setting unit sets the certain photography mode to the photography mode for the moving image, the function setting unit causes the common terminal to function as either of an input terminal inputting a synchronizing signal for the moving image, the synchronizing signal being for pairing a timing of photographing of a plurality of imaging apparatuses including the imaging apparatus, and an output terminal outputting a synchronizing signal for the moving image, the synchronizing signal being for pairing a timing of photographing of the plurality of imaging apparatuses including the imaging apparatus, to achieve the first function, and, when the photography mode setting unit sets the certain photography mode to the photography mode for the still image, the function setting unit causes the common terminal to function as a trigger signal output terminal to achieve the second function, wherein the trigger signal is for causing an electronic flash to emit light. when the photography mode setting unit sets the certain photography mode to the photography mode for the moving image, the function setting unit causes the common terminal to function as either of an input terminal inputting a synchronizing signal for the moving image, the synchronizing signal being for pairing a timing of photographing of a plurality of imaging apparatuses including the imaging apparatus, and an output terminal outputting a synchronizing signal for the moving image, the synchronizing signal being for pairing a timing of photographing of the plurality of imaging apparatuses including the imaging apparatus, to achieve the first function, and, when the photography mode setting unit sets the certain photography mode to the photography mode for the still image, the function setting unit causes the common terminal to function as a trigger signal output terminal to achieve the second function, wherein the trigger signal is for causing an electronic flash to emit light.