An image forming apparatus includes an image forming unit, an intermediate transfer member, a power source, and a control unit configured to perform a mode to output a test chart which is formed by transferring a plurality of test toner images from the intermediate transfer member to a plurality of sheets of the recording material. In a case where a jam occurred during execution of the mode, the control unit is configured to resume the mode after the jam has been recovered. In a case where the control unit resumes the mode after the jam has occurred during the execution of the mode, the control unit is configured to resume the mode from a first sheet of the plurality of sheets of the recording material regardless of a number of sheets of the recording material not discharged due to the jam.

An image forming apparatus includes: a gear that transmits a drive force, which is supplied from a drive unit, to a photosensitive drum; a formation processing unit that, at arrival of each of specific formation timings, uses the photosensitive drum thereby to form a to-be-detected toner image that is based on a to-be-detected image having a specific density; an acquisition processing unit that acquires a variation width of a density in the to-be-detected toner image formed by the formation processing unit; and a determination processing unit that determines a failure timing of the gear based on the variation width for each of the formation timings.

An image forming apparatus forms a coverage rate adjustment patch having a coverage rate corresponding to a difference between a coverage rate measured by a coverage rate measurement unit and a coverage rate of an adjustment image pattern together with an adjustment image pattern by using the exposure device and the developing device in the calibration.

An image forming apparatus includes an image forming portion, an image bearing member, a transfer member, a voltage source, a density detecting portion, a display portion, a controller, and an operating portion. The controller is capable of executing an operation in a mode in which a test chart for adjusting a transfer voltage is outputted, and setting information on the transfer voltage set for during transfer on the basis of a detection result when the test chart is detected by the detecting portion is displayed at the display portion and is checked by user. The controller causes the display portion to display setting information on the basis of a correcting value and causes the user to check the setting information in the operation in the mode executed after the correcting value is inputted from the operating portion.

An image forming apparatus includes an image forming unit configured to form an image on an image carrier, a transfer unit configured to transfer the image from the image carrier to a sheet, a reader configured to read a pattern image on the sheet while conveying the sheet, a sensor configured to measure a measuring image on the image carrier, and a controller configured to control the image forming unit to form the pattern image and the measuring image while forming images on a plurality of sheets, control the reader to read the pattern image, control the sensor to measure the measuring image, and generate an image forming condition based on a result of reading the pattern image by the reader and a result of measuring the measuring image by the sensor.

An image forming apparatus includes a platen on which an original is to be placed, a feeder configured to feed an original placed on a tray, a sensor configured to detect a sheet on the tray, a lamp provided to the feeder, a reader configured to read the original placed on the platen and to read the original conveyed by the feeder, an image forming unit configured to form an image on a sheet, and a controller. The controller is configured to control the image forming unit to form a first test image on a sheet, control the reader to read the first test image formed on the sheet placed on the platen, control a density of the image to be formed by the image forming unit based on a reading result of the first test image.

An image forming apparatus, configured to operate in first and second modes of which color gamut is different from each other, includes an exposure unit configured to expose a photosensitive drum; a developing roller configured to form a toner image; a detection unit configured to detect density of the toner image transferred to an intermediate transfer member; and a controller configured to adjust the density based on a value of input image data. A dithering process for the controller's controlling of the exposure unit is different depending on whether the operation is in the first mode or the second mode, and in at least a part of the input image data, the density of the toner image formed by the dithering process in the first mode is higher than the density of the toner image formed by the dithering process in the second mode.

An image forming method, an image forming apparatus, and a storage medium are provided in embodiments of the present disclosure. The method includes rotating an image carrier along a preset direction, where the image carrier at least includes a first region and a second region; and simultaneously applying voltages to a first image forming module and a second image forming module, such that the first image forming module forms a first image on the first region of the image carrier based on the voltages, and the second image forming module forms a second image on the second region of the image carrier based on the voltages. Each of the first image and the second image includes a plurality of patterns with different concentrations; and a quantity of patterns in the first image and the second image is determined based on a first preset distance.

A processor derives a plurality of unit density values which are each an average value of sensed densities for each of a plurality of unit areas sectioned for each unit length in a test toner image. The processor derives a weighted average of the plurality of unit density values to derive a test image density used for adjusting a control parameter in a printing portion. The unit length is a greatest common factor of two target lengths corresponding to perimeters of two types of target rotating members out of the plurality of rotating members. When a number of the plurality of unit areas is represented by n, n is a value obtained by subtracting 1 from an added value of a first constant and a second constant. The first constant and the second constant are values obtained by respectively dividing the two target lengths by the unit length.

An image forming apparatus includes an image bearing member, a transfer device, a voltage applying portion, a fixing device, and a controller. During execution of an operation in an output mode, the controller is capable of selectively executing: an operation in which test images formed on a first side of a first recording material are fixed and then the first recording material is outputted without forming the test images on a second side of the first recording material and then in which a second recording material is passed through the fixing device without forming the test images on a first side of the second recording material and then the test images are transferred onto a second side of the second recording material.