A downtime relating to formation and detection of a detection image is reduced. An image forming apparatus includes a controller configured to calculate a first conversion unit to convert a gradation of input image data so that density output for the input image data becomes a first density output characteristic based on a first detection result of the detection image detected by a density sensor in a first mode. The controller generates a second conversion unit to convert the gradation of the input image data so that the density output for the input image data becomes a second density output characteristic in a second mode based on the detection result in the first mode and correction information, and further updates the correction information based on a second detection result of the detection image detected by the density sensor in the second mode and the first detection result.

An image forming apparatus includes a storage unit and a charging amount acquisition unit. The charging amount acquisition unit forms a measurement toner image on the image carrier while changing the frequency of the alternating current voltage of the development bias, acquires a tilt of a measurement straight line representing a relationship between the change amount of the frequency and a density change amount of the measurement toner image based on the change amount of the frequency and a result of detecting density of the measurement toner image in the density detecting unit, and acquires the charging amount of the toner based on the acquired tilt of the measurement straight line and the reference information in the storage unit.

An electrophotographic imaging device having a method of printing which includes determining whether a duty cycle state in the imaging device has changed; selecting one of a full toner density calibration and a partial toner density calibration based on the determining; performing the one of the full toner density calibration and the partial toner density calibration; identifying a toner density to be applied during printing as a result of the performing; developing a toned image having a toner density equal to the toner density identified; and printing the toned image on a media sheet, wherein the full toner density calibration is skipped upon at least a determination that the duty cycle state has remained the same.

An electrophotographic imaging device having a method of printing which includes determining whether a duty cycle state in the imaging device has changed; selecting one of a full toner density calibration and a partial toner density calibration based on the determining; performing the one of the full toner density calibration and the partial toner density calibration; identifying a toner density to be applied during printing as a result of the performing; developing a toned image having a toner density equal to the toner density identified; and printing the toned image on a media sheet, wherein the full toner density calibration is skipped upon at least a determination that the duty cycle state has remained the same.

A downtime relating to formation and detection of a detection image is reduced. An image forming apparatus includes a controller configured to calculate a first conversion unit to convert a gradation of input image data so that density output for the input image data becomes a first density output characteristic based on a first detection result of the detection image detected by a density sensor in a first mode. The controller generates a second conversion unit to convert the gradation of the input image data so that the density output for the input image data becomes a second density output characteristic in the second mode based on the detection result in the first mode and correction information, and further updates the correction information based on a second detection result of the detection image detected by the density sensor in the second mode and the first detection result.

An electrophotographic imaging device having a method of printing which includes determining whether a duty cycle state in the imaging device has changed; selecting one of a full toner density calibration and a partial toner density calibration based on the determining; performing the one of the full toner density calibration and the partial toner density calibration; identifying a toner density to be applied during printing as a result of the performing; developing a toned image having a toner density equal to the toner density identified; and printing the toned image on a media sheet, wherein the full toner density calibration is skipped upon at least a determination that the duty cycle state has remained the same.

An image forming apparatus includes: an image forming portion that includes a developing portion configured to supply toner to an image bearing member bearing an electrostatic latent image formed thereon to develop the electrostatic latent image as a toner image, and is configured to form a toner image on a long paper sheet; a notification portion configured to notify a user about information; and a control portion configured to calculate, in accordance with coverage of a toner image that is a target of image formation, a toner image formation distance with which successive image formation is possible without forcibly discharging degraded toner from the developing portion, and to control the notification portion to notify the calculated toner image formation distance as a first toner image formation distance.

An image forming apparatus includes an image carrier that holds an image, which is formed by developing a latent image and which is transferred onto a recording medium, a developing device that is disposed adjacent to the image carrier and that develops the latent image, a light-reflection-type sensing unit that is disposed below the developing device in a vertical direction and that detects the image on the image carrier, and a guiding member that guides the recording medium, which is transported between the developing device and the sensing unit, and that covers an upper side of the sensing unit in the vertical direction in a state where a space is ensured on an optical path of the sensing unit.

An image forming apparatus receives a print setting for image data, determines a density correction table to be applied to a position of a pixel in the image data based on the received print setting from among a plurality of stored density correction tables, and corrects a density of the image data using the determined density correction table.

An image forming apparatus includes: an image forming unit configured to form an image pattern on a medium, a predetermined image repeatedly appearing in a first cycle in a sub scanning direction in the image pattern; a density detector configured to optically detect a density of the image pattern in the sub scanning direction; a cyclic image detector configured to detect a feature image having a second cycle corresponding to the first cycle in accordance with a result of the detection; and a state determining unit configured to determine whether a cycle depending on an outer circumference of a rotary member included in the image forming apparatus corresponds to the second cycle when the feature image is detected by the cyclic image detector, and determine that a state of the rotary member has deteriorated when the cycle depending on the outer circumference is determined to correspond to the second cycle.