An image forming apparatus includes a latent image bearer to bear a plurality of halftone images having a same image density and a high-density image located one cycle downstream of the latent image bearer from at least one of the plurality of halftone images, a transferor to apply a predetermined transfer voltage to transfer the plurality of halftone images and the high-density image, a transfer electric field forming target to bear the plurality of halftone images and the high-density image transferred from the latent image bearer, a detector to detect image densities of the plurality of halftone images on the transfer electric field forming target, and a controller to determine a primary transfer voltage applied at a time of image formation, based on image density variations of the plurality of halftone images detected by the detector.

An integrated sensor has a density detection sensor, a sensor board, and a potential sensor pattern. The density detection sensor detects the density of a toner image formed on a toner image carrying member. On the sensor board, the density detection sensor is mounted. The potential sensor pattern is provided on the sensor board, and detects the potential of the toner image.

An image forming apparatus including: a developing roller configured to develop an electrostatic latent image on a photosensitive drum to form a toner image; a belt onto toner image is transferred; a detection unit configured to detect a density of an image for detection formed on the belt; and a controller configured to perform hue adjustment based on a detection result of the detection unit, wherein the image forming apparatus performs image formation in a second mode using a color gamut different from a color gamut in a first mode, and the controller obtains a lookup table, which indicates a correlation between image data to be used and input image data in the second mode, based on the detection result in the first mode and a correlation of density between the first mode and the second mode.

An image forming apparatus comprises a reading section configured to read a first image on a sheet, an image forming section configured to forma second image on the sheet, a fixing section configured to heat the sheet to fix the second image on the sheet, and a processor. The processor is configured to determine a color of the read first image, select a decolorable toner based on the determined color, and set a target temperature of the fixing section to a temperature that is below a decoloring temperature of the decolorable toner, and above both a decoloring temperature of a decolorable toner having the determined color and a fixing temperature for the decolorable toner.

An information processing apparatus includes: a setting unit configured to set one or more colorimetric regions in an image to be formed based on image data; and a transmission unit configured to transmit a print job to an image forming apparatus, the print job including the image data and colorimetric region information indicating the one or more colorimetric regions. The setting unit has a first mode under which the setting unit selects, based on a selection criterion, a colorimetric region in the image to be formed based on the image data, and a second mode under which a user designates the colorimetric region.

An image forming apparatus includes an image forming device, a gradation adjustment mark adder and a hardware processor. The hardware processor monitors and adjusts a gradation characteristic based on a result of scanning a gradation adjustment mark. The hardware processor makes a determination as to whether to form the gradation adjustment mark overlapping an image area of an image based on image data. If it is determined to form the gradation adjustment mark overlapping the image area, the hardware processor controls the gradation adjustment mark adder to add gradation adjustment mark information to the image data in the image area.

An image forming apparatus includes a latent image bearer to bear a plurality of halftone images having a same image density and a high-density image located one cycle downstream of the latent image bearer from at least one of the plurality of halftone images, a transferor to apply a predetermined transfer voltage to transfer the plurality of halftone images and the high-density image, a transfer electric field forming target to bear the plurality of halftone images and the high-density image transferred from the latent image bearer, a detector to detect image densities of the plurality of halftone images on the transfer electric field forming target, and a controller to determine a primary transfer voltage applied at a time of image formation, based on image density variations of the plurality of halftone images detected by the detector.

A specification part of an information processing device specifies, by using image data for a correction chart defining a plurality of patch regions having different color values, a target characteristic indicating a relation between the color value and a first colorimetric value of a first patch image as a laminated image of a special color image and a colored image that correspond to each of the patch regions formed by the device through the 2-path printing. A generation part of the device generates a correction table for correcting the color value so that a measured characteristic comes close to the target characteristic, the measured characteristic indicating a relation between the color value and a second colorimetric value of a second patch image as the laminated image corresponding to each of the patch regions formed by the device through the 1-path printing using the image data for a correction chart.

An image forming apparatus includes: a transfer member which transfers a toner image formed on an image bearing member to a transfer material; a transfer bias application unit which applies bias to the transfer member; a controller capable which executes a mode for making a first bias applied to a first predetermined area arranged at a leading edge of a transfer material with respect to a conveying direction of the transfer material to be less than a second bias applied to a second predetermined area arranged in a central area of the transfer material; and an obtaining portion which obtains image information of an image formed in each area obtained by dividing an area corresponding to the leading edge area into plural pieces in the width direction, wherein the controller controls the first bias based on image information obtained by the obtaining portion at the time of the mode.

An integrated sensor has a density detection sensor, a sensor board, and a potential sensor pattern. The density detection sensor detects the density of a toner image formed on a toner image carrying member. On the sensor board, the density detection sensor is mounted. The potential sensor pattern is provided on the sensor board, and detects the potential of the toner image.