Abstract: An image forming apparatus includes a toner image forming device for forming a color image. The toner image forming device forms a first color test image and a second color test image superposedly on an image conveying member so that at least one of a screen angle and a screen ruling with respect to the first color test image is different from that with respect to the second color test image. The image forming apparatus further includes a detecting device for detecting a distribution of heights of the first and second color test images formed superposedly on the image conveying member by the toner image forming device, and a control device for controlling a toner image forming condition of the toner image forming device on the basis of the distribution detected by the detecting device.

Abstract: A set of adjustment pattern images includes first adjustment pattern images and second adjustment pattern images to be formed on a first side and a second side of a recording sheet, respectively, by an image forming apparatus. The set of adjustment pattern images is employed to adjust an image forming position by the image forming apparatus such that an image forming position of the first adjustment pattern images is aligned with an image forming position of the second adjustment pattern images. The set of adjustment pattern images includes at least two first adjustment pattern images that are spaced from each other and at least two second adjustment pattern images that are spaced from each other, and the first adjustment pattern images on the first side and the second adjustment pattern images on the second side are arranged alternately with each other.

Abstract: An image forming apparatus includes an image forming unit configured to from a measurement image on a recording paper by a color material, a fixing unit configured to fix the measurement image onto the recording paper by heating, a measurement unit configured to measure the measurement image fixed onto the recording paper downstream of the fixing unit in a conveyance direction of the recording paper, and a control unit configured to perform control such that a period of time from when the recording paper passes through the fixing unit until the measurement unit measures color of the measurement image is longer than a period of time from when the recording paper passes through the fixing unit until the measurement unit measures density of the measurement image.

Abstract: An image forming apparatus includes an image forming unit, a decision unit, an output unit, a control unit, and a setting unit. The image forming unit forms an image on an image bearing member. The decision unit decides a first image forming condition of the image forming unit for forming the image at a width that is wider than a predetermined width. The output unit outputs a signal in accordance with the thickness of the image. The control unit causes the image forming unit to form a measurement image having a width that is narrower than or equal to the predetermined width. The setting unit sets a second image forming condition of the image forming unit so that the thickness of the image that is narrower than or equal to the predetermined width becomes thinner than or equal to the predetermined thickness.

Abstract: Disclosed herein is an image forming apparatus that has a developing unit, an intermediate transfer body, and a transfer roller and may prevent contamination of the transfer roller and a printing medium by the toner remaining in a test pattern forming area of the intermediate transfer body. The image forming apparatus includes a developing unit to allow an image to be formed by a developing agent, an intermediate transfer body provided with an image forming area and a test pattern forming area, the image being transferred from the developing unit to the image forming area and the test pattern forming area, and a transfer roller allowing the image to be transferred from the image forming area to a printing medium, wherein a maximum transfer length of the transfer roller is less than a maximum image forming length of the developing unit.

Abstract: An image forming apparatus includes a secondary transfer belt that rotates, an imaging unit for forming a patch image of toner on the secondary transfer belt, and an upstream brush and a downstream brush coming into contact with the secondary transfer belt in a rotating state to remove the patch image from on the secondary transfer belt. A length p of the patch image formed by the imaging unit along a rotational direction of the secondary transfer belt, a distance b1 over which the secondary transfer belt rotates while the upstream brush makes one turn, and a distance b2 over which the secondary transfer belt rotates while the downstream brush makes one turn satisfy an expression: p?|b1?b2|.

Abstract: The image forming apparatus detects a color deviation amount in a timing when a developing roller separates from or contacts a photosensitive drum to set a difference in peripheral velocities between the photosensitive drum and an intermediate transfer belt or a transfer material conveying belt based on the color deviation amount and information about the use degree of the intermediate transfer belt.

Abstract: An image processing method for generating a halftone pattern for forming an image according to input image data includes a step of forming first and second shade patterns to be developed by first and second toners, respectively. The second toner is identical in color to the first toner and different in shade from the first toner, and the second shade pattern is shifted from the first shade pattern.

Abstract: One aspect of the present invention provides an information processing apparatus for determining a height of a toner image formed on a carrier, the apparatus comprising: a control unit configured to control an amount of irradiation light based on whether laser light irradiated by an irradiation unit is irradiated onto the toner image; an acquisition unit configured to acquire an image obtained by capturing reflected light of the laser light irradiated by the irradiation unit; and a determination unit configured to determine the height of the toner image based on the acquired image.

Abstract: An image forming apparatus can transfer a plurality of color component images onto a surface of a recording medium to form an image on the recording medium. The image forming apparatus includes a pattern generation part to generate information about an alignment pattern to be used for a calibration of an image forming, a plurality of stations each including a photosensitive drum to form an alignment pattern corresponding to each of a plurality of color components onto a carry belt or the recording medium, and a read part to detect a plurality of alignment patterns formed by the plurality of stations.

Abstract: An image forming apparatus includes an intermediate transfer body; a generating unit generating test pattern data; a storage unit storing a color displacement amount; a correcting unit correcting the test pattern data and image data based on the color displacement amount currently stored in the storage unit; a forming unit forming a test pattern based on the test pattern data corrected by the correcting unit on the intermediate transfer body at predetermined intervals, and forming an image based on the image data corrected by the correcting unit on the intermediate transfer body; a detecting unit detecting the test pattern formed on the intermediate transfer body; an updating unit determining an amount of change of the color displacement amount from a result of detection by the detecting unit, and updating the color displacement amount stored in the storage unit by using the amount of change of the color displacement amount.

Abstract: An image forming apparatus includes an image bearing member configured to bear an image with a toner, a transfer unit configured to transfer the image from the image bearing member onto a recording material, a conveying unit configured to convey the recording material having the image on a first side thereof to transfer the image onto a second side of the recording material, and a control unit configured to control an operation for forming a test image in an interval region between a first image, formed on the image bearing member, and a second image formed subsequently to the first image on the image bearing member. The control unit is configured to permit formation of the test image in the image interval region when the second image is an image to be transferred onto a first side of the recording material and configured to prevent formation of the test image in the image interval region when the second image is an image to be transferred onto a second side of the recording material.

Abstract: According to an embodiment, provided is an image forming apparatus that forms an image on a moving body using toner. The image forming apparatus includes a pattern creating device that creates a first pattern for toner density detection and a second pattern for positional deviation detection on the moving body, the first pattern and second pattern being disposed to be arrayed in a main-scanning direction; a reflecting optical sensor including an emitting system that includes at least three light-emitting elements of which positions at least in the second direction are different and a light-receiving system that includes at least three light-receiving elements that receive light beams that are emitted from the emitting system and reflected from the first pattern and second pattern; and a processing device that obtains toner density information and positional deviation information simultaneously based on an output signal of the light-receiving system.

Abstract: An image forming apparatus includes an image carrier; an image forming unit; a processor for controlling the image forming unit according to a predetermined image forming condition setting data; an image density sensor to detect an image density of the toner pattern formed on the image carrier; a reference rotary position detector; an image density fluctuation data acquisition unit to obtain an image density fluctuation data of more than one circumferential length of the photoreceptor drum with reference to the reference rotary position detected by the reference rotary position detector based on a result related to the toner pattern formed on the image carrier detected by the image density sensor; and a correction data generator to generate a correction data to correct a reference image forming condition setting data with a correction amount corresponding to each rotary position of the rotary member to thus reduce the image density fluctuation.

Abstract: An image forming apparatus includes an image bearer, a toner image forming unit, a detector, and a controller to adjust an image forming condition based on a detection result by the detector. During a non-printing period, multiple toner patterns are formed in an end and center portions of the image bearer in a direction perpendicular to a direction in which the image bearer moves, and a smaller number of toner patterns selected from the multiple toner patterns are formed in a non-image area, in the end portion of the image bearer, during a printing period. The controller determines a target density X of the smaller number of toner patterns by X=H (a mean detected density of the multiple toner patterns formed in the end portion)×J (a predetermined reference value)/I(a mean detected density of the multiple toner patterns formed in the end portion and in the center portion).

Abstract: The image forming apparatus includes a CPU that performs control to form an inspection image for determining whether or not banding is suppressed to be smaller than a predetermined threshold value; and a density sensor that detects an intensity of banding periodically occurring in a sub-scanning direction of the formed inspection image. If based the detected banding intensity, the CPU has determined that the banding is not suppressed to be smaller than the predetermined threshold value, the CPU performs control to not perform banding correction or performs control to re-set a relationship between a phase of a rotary member and correction information.

Abstract: An image forming apparatus includes an image bearing member, an image forming unit configured to form a toner image on the image bearing member, a conveyance member configured to transfer the toner image formed on the image bearing member onto a recording material and to convey the recording material, a detection member configured to detect the toner image on the conveyance member, and a control portion configured to set a position of a toner image, to be formed by the image forming unit, relative to the recording material based on a result obtained by forming a test toner image so as to extend over the conveyance member and an end portion of the recording material, transferring the formed test toner image onto the conveyance member and the recording material, and causing the detection member to detect the test toner image transferred onto the conveyance member.

Abstract: An image forming apparatus includes a patch image generation unit which generates a patch image for image density detection disposed between toner images, and a patch density sensor which detects a density of the patch image. In order to prevent the output quality of a printed image from varying with the type of paper use, a correction unit performs correction processing to match a detected density and a target density by comparing the detected density of the patch image detected by the patch density sensor and the target density of the patch image which is set in advance, a toner deposit control unit controls a toner deposit when the image forming unit forms an image based upon image data and when the patch image generation unit generates the patch image, and a paper interval control unit controls an interval between consecutive papers.

Abstract: An image forming apparatus includes an image bearing body, a latent image forming section that forms a latent image on the image bearing body, a development section that develops the latent image using toner, a transfer section that transfers a toner image to a transferred body, a pressuring and contacting section that pressures and contact the transfer section against and with the image bearing body via the transferred body, a cleaning blade that removes residual toner, and a controller. The controller analyzes a print pattern of the image to be formed on the sheet. The controller controls the pressuring and contacting section to change a contact state between the image bearing body and the transferred body while adjusting an image patch formed in a domain corresponding to an inter-sheet portion between the sheet and the next sheet on the image bearing body according to an analysis result.

Abstract: An image forming device includes an image forming section, a CPU and memory storing executable instructions that, when executed by the CPU, cause the image forming device to provide functions including a data acquisition section, a mismatch correction section and a control section. The data acquisition section is configured to acquire a variation in factor that causes a mismatch of a parameter. The control section is configured to estimate an amount of mismatch of the parameter based on the variation and to send a request for measuring the amount of mismatch to the mismatch correction section when the estimated amount is equal to or larger than a reference value. The control section is also configured to alter at least one of calculation factors used for estimating the amount of mismatch and the reference value according to the measured amount.

Abstract: When an input image is to be formed on a sheet conveyed to a transfer roller, the exposure section is controlled and deviation correction is performed to offset the image forming position across the width of the sheet in response to the result of detection by a deviation sensor. By contrast, when pattern images are to be formed on a sheet in response to the instruction of the main control section, the image forming control section does not perform deviation correction in the process of forming a pattern image.

Abstract: Electrophotographic (EP) streaking compensation is performed. A tonescale is measured for each column and a per-column gain computed to compensate for variations. An adjustment tonescale is determined and a per-column adjustment-tonescale gain computed to correct for remaining error after the per-column gain is applied. The two corrections are used together to provide improved compensation quality.

Abstract: An image forming apparatus includes an image bearing member to bear a toner image, a transfer device to transfer the toner image onto a recording medium, and a moving device controller to control a moving device that moves the transfer device such that the moving device moves the transfer device to contact the image bearing member during transfer of the toner image on the image bearing member to the recording medium; separates the transfer device from the image bearing member as a toner patch on the image bearing member passes through the transfer area; and maintains the transfer device in contact with the image bearing member from a preceding transfer of a toner image to a succeeding transfer of a toner image during continuous printing, as at least one of areas between successive toner images on the image bearing member without the toner patch passes through the transfer area.

Abstract: In a registration mark, when toners of plural colors are divided into two groups of a low-reflectance group having a relatively low spectral reflectance and a high-reflectance group having a relatively high spectral reflectance in accordance with high and low levels of spectral reflectances with respect to light emitted by an optical sensor, a toner pattern that gives information of a toner-image formation position of a toner-image forming unit using the toner that belongs to the low-reflectance group includes a first pattern in which the toner that belongs to the high-reflectance group is distributed without a gap in a moving direction of the transferred member, and second patterns formed with the toner used by the toner-image forming unit, the second patterns being arranged on both sides of the first pattern in the moving direction of the transferred member without a gap with respect to the first pattern.

Abstract: When reading calibration chevrons during mark-on-belt (MOB) sensor timing calibration, cyan portions or legs of printed chevrons are detected in order to determine a timing window offset adjustment. Depending on which of the six cyan legs on the left side of the chevrons are detected, a determination can be made regarding whether the window needs to be started earlier or later. If only the first two cyan legs on the left side of the chevron are detected, then the MOB sensor timing window is beginning (and ending) too early and an appropriate adjustment can be made to cause the timing window to initiate later. If only the last two cyan legs on the left side of the chevron are detected, then the MOB sensor timing window is beginning (and ending) too late, and appropriate adjustment can be made to cause the timing window to initiate earlier.

Abstract: The development roller adheres toner to an electrostatic latent image on the photo conductor drum in order to develop a toner image. The pattern image generating unit develops two pattern images that are two sets of plural test patches for calibration on the photo conductor drum. Each one of the pattern images includes the test patches corresponding to densities in gradation. Further, the pattern image generating unit sets an interval between a top of the first pattern image and a top of the second pattern image so that a remainder for the interval divided by a density fluctuation pitch is larger than a length of the test patch. The density fluctuation pitch is the product of a periphery length of the development roller and a ratio between a rotating speed of the development roller and a rotating speed of the photo conductor drum.

Abstract: In the image processing device, the color conversion part converts the input value to an output value by using a color profile. The correction part corrects the output value to a corrected value by using a correction table. The update part updates the correction table based on a density patch. The first and second amount is an estimated amount of the color material to be consumed when corrected image data corrected by either using the updated correction table or using an initial correction table, respectively, is printed. When the amount determining part determines that the first amount is greater than the second amount, the modifying part modifies the color profile such that the output value in the modified color profile specifies a less amount of color material than an amount of color material specified by the output value in the unmodified color profile.

Abstract: An image forming apparatus includes an imaging unit configured to form pattern images in areas corresponding to positions at which toners including a specific color toner of a specific color are provided; a reading unit configured to read the formed pattern images; a color information detection unit configured to analyze color information of the read pattern images and detect the color information of the specific color toner; a position determination unit configured to determine the position at which the specific color toner is provided from a position at which the pattern image of the specific color is formed in the read pattern images; and a recording unit configured to record the detected color information of the specific color toner and the position at which the specific color toner is provided.

Abstract: There is provided an image processing apparatus which can suppress degradation of an image quality in a recording material save mode processing and obtain an effect of consumption amount reduction of recording material desired by a user at low costs. A recording material consumption amount at the time of applying first color conversion processing unit is predicted corresponding to inputted image data. The setting of a second color conversion processing is changed from a prediction value and a target value of the recording material consumption amount.

Abstract: An image forming apparatus includes an image forming device to form a toner image according to image data, a density adjustment toner pattern, and a timing adjustment toner pattern on an image bearer, a detector to detect the density adjustment toner pattern and the timing adjustment toner pattern, and an image density adjustment unit to execute image density adjustment based on an amount of toner adhering to the density adjustment toner pattern detected by the toner amount detector. The image density adjustment unit causes the image forming device to form the timing adjustment toner pattern before the density adjustment toner pattern is formed, and the image density adjustment unit adjusts a detection timing of the density adjustment toner pattern based on a detection timing of the timing adjustment toner pattern detected by the toner amount detector.

Abstract: A representative configuration of an image forming apparatus has a plurality of developing devices, each of which develops an electrostatic latent image formed on a photosensitive drum into a toner image using developer of plural colors. The image forming apparatus includes a density sensor which detects the amount of toner of the toner image for each color. In a case where it is determined that the amount of toner of any color departs from a predetermined range based on the detection result of the density sensor, development conditions of the rest of the developing devices, other than the developing device departing from the predetermined range, are changed such that the image densities developed by the respective developing devices are equal to each other.

Abstract: An image forming apparatus includes a printing unit configured to print an input print job including a plurality of pages, wherein, if it is determined that a remaining amount of a recording agent in a cartridge is less than or equal to a threshold value, the printing unit prints a portion of print data in the print job, temporarily stops printing, and displays a toner out message on a display unit to prompt a user to replace the cartridge, and repeats, if the user does not replace the cartridge after the toner out message is displayed, printing a portion of print data in the print job that is different from the print data that the printing unit has already printed, temporarily stopping printing, and displaying on the display unit the toner out message.

Abstract: A plurality of test patches each including a dark and light image which has density unevenness of a predetermined period in which the plurality of test patches are differentiated in phase difference relative to a phase of density unevenness induced by rotational unevenness occurring at a predetermined period in the motor for driving a photosensitive drum is formed. Then, density information of the plurality of test patches with is detected by a density sensor 41, and the phase of the density unevenness is obtained based on detection results (density information) of the plurality of test patches as well as based on a phase difference corresponding to a test patch whose density unevenness is a predetermined value in amplitude.

Abstract: An image forming apparatus has a detector that includes a toner density sensor arranged on the downstream side of a fixing section. When performing a control to determine an image forming condition of an image forming section based on the detection result of an image-adjusting pattern image obtained by the detector, the temperatures of a plurality of points in the axial direction of the fixing section are detected by a fixing temperature detector. Further, based on the temperature detection values obtained by the fixing temperature detector, a controller sets a detection area of the detector in a place where the fixing temperature is equal to a desired temperature, so that the detector detects the information about the image-adjusting pattern image at such place.

Abstract: In an image forming apparatus, a density adjustment unit causes to form a cleaner toner image on a surface of an image carrier and remove the cleaner toner image for density adjustment, and causes to form a test pattern after removing the cleaner toner image. The cleaner toner image is formed to cover a whole area on which the test pattern may be formed.

Abstract: In the case where a peripheral velocity of photosensitive drums differs from a peripheral velocity of an intermediate transfer belt, the peripheral velocity of the intermediate transfer belt or the peripheral velocity of the photosensitive drums is corrected. The velocity of the intermediate transfer belt is transiently varied in an image forming operation. Accordingly, a plurality of tonner patch patterns including toner patches are formed on the intermediate transfer belt, and the difference in peripheral velocity between the intermediate transfer belt and the photosensitive drums is estimated based on a difference between the displacements in the tonner patch patterns.

Abstract: An image forming apparatus includes: a detection unit detecting information about an image-adjusting pattern image fixed to a paper; a determination unit which, on the basis of an image-noise detecting pattern image that is formed on the paper prior to forming the image-adjusting pattern image, determines the presence or absence of an image noise generated in the image-adjusting pattern image; and a control unit. On the basis of the determination result of the determination unit, the control unit sets a detection region where the detection unit detects information about the image-adjusting pattern image, to a region where the image noise is not generated, and determines the image forming condition by using the information detected in the detection region.

Abstract: An image forming apparatus includes recording heads for ejecting recording liquids of colors onto a recording medium. The apparatus includes a reference-patch forming unit that records a reference patch, the reference patch being formed by overlaying dot array patterns recorded with the recording liquids of different colors, the dot array patterns having no correlation therebetween; a detection-patch-group forming unit that records a detection patch group including detection patches, each of the detection patches being formed by overlaying dot array patterns recorded with the recording liquids of the different colors, the dot array patterns having a same cycle of regular dot array, the detection patches being allocated with different misregistration amounts of the dot array patterns; and a color-misregistration correcting unit that corrects color misregistration based on results of comparison between color tone of the reference patch and color tone of each of the detection patches.

Abstract: An image forming apparatus includes movable first and second image bearing members, latent image forming units that form electrostatic latent images and latent index patterns, a movable belt member contacting the image bearing members, toner image transfer members that transfer toner images, obtained by depositing toner on the latent images, onto the belt member, latent pattern detectors that detect the latent index patterns, an adjusting portion that adjusts relative positions between the latent index patterns on the basis of detection results of the detectors, and a setting portion that sets a latent pattern transfer voltage, during image formation, on the basis of a detection result of one of the latent pattern detectors on condition that a plurality of test voltages are applied to one of the latent pattern transfer member during non-image formation.

Abstract: A spectral colorimetric apparatus for detecting a color of an image of a subject, including: an illumination optical system illuminating the subject on a detection surface; a spectral optical system including a spectral element spectrally separating the beam diffused by the subject and a light receiving element array detecting a spectral intensity distribution; and a guiding optical system for guiding a beam diffused by the subject, wherein: the detection surface is parallel to a spectral plane including a principal ray of a beam entering the spectral optical system and a principal ray of a beam spectrally separated; the principal ray of the beam enters the spectral optical system within the spectral plane obliquely to a line joining a center of the light receiving element array with a surface vertex of the spectral element; and a light receiving surface of the light receiving element array is orthogonal to the spectral plane.

Abstract: An image processing apparatus includes an image forming unit, an image control unit, a sensor, and a correction unit. The image control unit controls the image forming unit to perform toner refresh which is an operation of outputting deteriorated toner at a high density, and controls the image forming unit to form a predetermined pattern. The sensor measures a density value of the formed image. The correction unit corrects the toner density for a high-density operation using the value measured from the image formed during the toner refresh and corrects the toner density for at least a low-density operation using the value measured from the predetermined pattern.

Abstract: An image forming apparatus includes an image forming unit that forms, on an image bearing member, an image for adjusting operations of the image forming apparatus, a container that contains toner removed from the image bearing member, and a controller that controls formation of the image for adjusting the operations of the image forming apparatus so that after an amount of toner contained in the container reaches a threshold value, an amount of toner removed from the image bearing member and to be contained in the container is reduced to less than before the amount of toner contained in the container reaches the threshold value.

Abstract: An image forming apparatus includes: an image forming unit that forms a pattern image for image quality adjustment on an image carrier; a detection unit that detects the pattern image for the image quality adjustment; an image quality adjustment control unit that controls an image quality adjustment process in accordance with a result of detection of the detection unit; a reception unit that receives a color mode selected from among a plurality of kinds of color modes; and a calculation unit that calculates a total pattern length so that a total length of the pattern image for the image quality adjustment in a sub-scanning direction is equal in any of the color modes, wherein the image forming unit forms the pattern image for the image quality adjustment so that the total length of the pattern image for the image quality adjustment is equal to the calculated total pattern length.

Abstract: Various systems, methods, and programs embodied in computer readable media are provided for calibration of at least one half-tone density in a printer. In one approach, a method is provided comprising the steps of acquiring a plurality of half-tone density values from a respective plurality of test patches generated on a belt in the printer over a period of time, each of the test patches embodying an intended half-tone density, generating a mathematically smoothed half-tone density value from the half-tone density values, and calibrating a half-tone density in the printer based upon the mathematically smoothed half-tone density value.

Abstract: An image forming apparatus includes an image forming unit configured to form a measurement image on a sheet, a measurement unit configured to radiate light on the measurement image via a transparent window, and measure the light reflected from the measurement image, a white reference plate of which a white level is measured by the measurement unit, a black member of which a black level is measured by the measurement unit, and a determination unit configured to determine, based on a change in a measurement result of the white reference plate and a change in a measurement result of the black member measured by the measurement unit, whether the white reference plate, the black member, or the window is soiled.

Abstract: An image forming apparatus performs pseudo gradation processing using dithering, and includes an image carrier; a plurality of light-emitting element arrays arranged in a main-scanning direction and including a plurality of light-emitting elements; an image forming unit performing lighting control of the arrays and forming a pattern image on the image carrier; a detecting unit detecting a density of the pattern image; a position detecting unit detecting a position in the main-scanning direction of the detecting unit with respect to the light-emitting element arrays; a determining unit that, based on the detected position, determines whether the detecting unit is positioned at a proper detection position with respect to the pattern image on which noise has no effect; and an operation control unit that, when the detecting unit is positioned at the proper detection position, performs an image density detection operation on the pattern image using the detecting unit.

Abstract: Disclosed is an image forming apparatus includes: an image forming section, a control section, and a magnification factor adjusting section. The control section employs an index signal based on a detected result of a light beam irradiation, for controlling an operation timing of the image forming section in the toner image area; and when forming the band-shaped toner image on the area between the toner image areas being adjacent to each other, while controlling the magnification factor adjusting section to implement an operation for adjusting the image magnification factors in parallel, the control section employs a timing signal, created otherwise without depending on the detected result of the light beam irradiation, for controlling the operation timing of the image forming section.

Abstract: An image forming system is provided. The image forming system includes an image forming apparatus configured to form a mark for detecting at least one of a position deviation and a density deviation and obtains a correction amount by detecting the mark, the image forming system comprising: an identification unit configured to identify an image characteristic of an image to be printed according to at least one of a positional relationship between colors, a gradation distribution and a resolution, and a selecting unit configured to select a choice from multiple choices containing at least two choices of: only position deviation; only density deviation; and both position deviation and density deviation, according to the image characteristic identified by the identification unit, wherein the image forming apparatus is configured to form the mark for obtaining the correction amount according to the choice selected by the selecting unit.

Abstract: An image forming apparatus uses the difference in time taken for each patch to reach a color sensor, which occurs upon reversing the conveyance direction of a printing material. Due to this difference in time, the temperature of the printing material in detection by the color sensor differs among the respective patches. The error of a colorimetric value due to thermochromism is reduced by placing a patch with a colorimetric value which has a low temperature dependence so as to be detected earlier, and a patch with a colorimetric value which has a high temperature dependence so as to be detected later.

Abstract: Embodiments described herein include a multi-color printing system in which color-to-color registration errors due to cyclical belt motion errors are minimized. A belt for transporting a substrate media or at least a partial image into a plurality of panels is segmented. A first one of the panels has a first location on the belt for receiving substrate media or a partial image. A first belt motion error value corresponding to the first one of the panels on the belt is identified and at least one image marking unit is calibrated to counteract the first belt motion error corresponding to the first one of the panels.