An image processing device (100 100A 100B 100C) comprising: an acquisition section (110 110A 110B 110C) configured to acquire first still image data and performance information (I1 I2) indicating a printing performance specifying a reflection brightness corresponding to a paper type of a printing device (200 200A 200B), the first still image data being obtained through imaging and having a dynamic range of brightness comprised in a first dynamic range; a converter (120 120C) configured to convert, using the performance information (I1 I2), the first still image data acquired by the acquisition section into second still image data, the second still image data having a dynamic range of brightness comprised in a second dynamic range, said second dynamic range having a smaller dynamic range of brightness than the first dynamic range, and an output section configured to output the second still image data converted by the converter (120 120C) to the printing device (200 200A 200B), characterized in that, the performance information (I1 I2) comprises input from the image processing device, based on a printed result, said printed result being obtained by printing a specific pattern on paper used for printing by the printing device (200 200A 200B), the second dynamic range then comprises a dynamic range of brightness determined for the printed result according to the input from a user, wherein the specific pattern comprises a plurality of numbered patterns in two groups, each pattern comprising an area of either black or white as a comparative reference and each further comprising an area of gray, the patterns of a first group each comprising a black area and respectively reduced in darkness of the gray area and the patterns of a second group comprising a white area and respectively reduced in darkness of the gray area, the numbers of the patterns being arranged as increasing sequentially from the pattern comprising a black area and the darkest gray area to the pattern comprising a white area and the lightest gray area, the input from the user comprising a pair of numbers relating to the smallest pattern number among patterns comprising a black area in which the user can recognize gradation difference between black and gray and the largest pattern number among patterns comprising a white area in which the user can recognize gradation difference between white and gray, the smallest and largest pattern numbers of said input being associated in advance with a brightness range to be selected by the image processing device (100 100A 100B 100C) as the second dynamic range. an acquisition section (110 110A 110B 110C) configured to acquire first still image data and performance information (I1 I2) indicating a printing performance specifying a reflection brightness corresponding to a paper type of a printing device (200 200A 200B), the first still image data being obtained through imaging and having a dynamic range of brightness comprised in a first dynamic range; a converter (120 120C) configured to convert, using the performance information (I1 I2), the first still image data acquired by the acquisition section into second still image data, the second still image data having a dynamic range of brightness comprised in a second dynamic range, said second dynamic range having a smaller dynamic range of brightness than the first dynamic range, and an output section configured to output the second still image data converted by the converter (120 120C) to the printing device (200 200A 200B), the performance information (I1 I2) comprises input from the image processing device, based on a printed result, said printed result being obtained by printing a specific pattern on paper used for printing by the printing device (200 200A 200B), the second dynamic range then comprises a dynamic range of brightness determined for the printed result according to the input from a user, wherein the specific pattern comprises a plurality of numbered patterns in two groups, each pattern comprising an area of either black or white as a comparative reference and each further comprising an area of gray, the patterns of a first group each comprising a black area and respectively reduced in darkness of the gray area and the patterns of a second group comprising a white area and respectively reduced in darkness of the gray area, the numbers of the patterns being arranged as increasing sequentially from the pattern comprising a black area and the darkest gray area to the pattern comprising a white area and the lightest gray area, the input from the user comprising a pair of numbers relating to the smallest pattern number among patterns comprising a black area in which the user can recognize gradation difference between black and gray and the largest pattern number among patterns comprising a white area in which the user can recognize gradation difference between white and gray, the smallest and largest pattern numbers of said input being associated in advance with a brightness range to be selected by the image processing device (100 100A 100B 100C) as the second dynamic range.