A control apparatus comprising: a display; and a central processing unit that is configured to: cause the display to display a plurality of jobs as a list on a screen; receive, via the screen, a selection of an adjustment target job, as a first job, from among the jobs in the list; obtain first document image data associated with the first job; obtain read image data of a color sample associated with the first document image data; generate a first color conversion parameter regarding a color conversion of the first document image data based on the first document image data and the read image data; automatically update a setting of the first job in a state corresponding to the first color conversion parameter by setting the first color conversion parameter in the first job; and add prohibiting information to the first color conversion parameter to prohibit the first color conversion parameter from being set in a job other than the first job, wherein when setting a color conversion parameter for the first job, the CPU is configured to cause the display to display a setting screen where the first color conversion parameter is displayed as an option, and when setting a color conversion parameter for the other job, the CPU is configured to cause the display to display a setting screen of the color conversion parameter for the other job and to prohibit the first color conversion parameter to be displayed as an option. a display; and a central processing unit that is configured to: cause the display to display a plurality of jobs as a list on a screen; receive, via the screen, a selection of an adjustment target job, as a first job, from among the jobs in the list; obtain first document image data associated with the first job; obtain read image data of a color sample associated with the first document image data; generate a first color conversion parameter regarding a color conversion of the first document image data based on the first document image data and the read image data; automatically update a setting of the first job in a state corresponding to the first color conversion parameter by setting the first color conversion parameter in the first job; and add prohibiting information to the first color conversion parameter to prohibit the first color conversion parameter from being set in a job other than the first job, wherein cause the display to display a plurality of jobs as a list on a screen; receive, via the screen, a selection of an adjustment target job, as a first job, from among the jobs in the list; obtain first document image data associated with the first job; obtain read image data of a color sample associated with the first document image data; generate a first color conversion parameter regarding a color conversion of the first document image data based on the first document image data and the read image data; automatically update a setting of the first job in a state corresponding to the first color conversion parameter by setting the first color conversion parameter in the first job; and add prohibiting information to the first color conversion parameter to prohibit the first color conversion parameter from being set in a job other than the first job, wherein when setting a color conversion parameter for the first job, the CPU is configured to cause the display to display a setting screen where the first color conversion parameter is displayed as an option, and when setting a color conversion parameter for the other job, the CPU is configured to cause the display to display a setting screen of the color conversion parameter for the other job and to prohibit the first color conversion parameter to be displayed as an option.