An image forming apparatus that is capable of finding density of an output image with high accuracy even if reflectance of an image bearing member varies. A conversion unit converts image data based on a conversion condition. An image forming unit forms an image based on the converted image data. A measurement unit measures irregular reflection light from a measurement image on the image bearing member. A controller controls the image forming unit to form measurement images, controls the measurement unit to measure irregular reflection light from an area on the image bearing member where the measurement images are not formed, controls the measurement unit to measure the irregular reflection light from the measurement images, selects a measurement result from among measurement results of the measurement images based on the measurement result of the area, and generates the conversion condition based on the selected measurement result.

A developing device includes a hardware processor that performs control not to cause an image to be formed on an image bearing member by a first developer bearing member and to cause a first image to be formed on the image beating member by a second developer bearing member, in which the hardware processor corrects developing conditions of the plural developer bearing members based on a developability detection result of the first image formed by the second developer bearing member.

An image forming apparatus includes a latent image bearer configured to bear a latent image and a developing device configured to develop the latent image on the latent image bearer with developer. The developing device includes a plurality of developer bearers configured to bear the developer. The image forming apparatus further includes a rotation position detector configured to detect a rotation position of at least one of the plurality of developer bearers, a common power source configured to apply a developing bias to each of the plurality of developer bearers, and circuitry configured to cause the common power source to periodically vary the developing bias. The circuitry is configured to cause the plurality of developer bearers to rotate in a same rotation period; and vary an output value of the developing bias in a same period as the rotation period based on a detection result by the rotation position detector.

An image forming apparatus forms a first image by adjusting a photosensitive member potential to a first charging potential and adjusting a developing potential to a first developing potential, and forms a second image by adjusting the member potential to a second charging potential and adjusting the developing potential to a second developing potential, but not causing an exposure unit to expose a photosensitive member, and forms a third image by adjusting the developing potential to a third developing potential, but not causing a charging unit to charge the member and not causing the exposure unit to expose the member. The apparatus detects a streak image based on read data of the first, second and third images, and read data corresponding to a non-image region of the test sheet.

An image forming apparatus includes an image forming unit configured to form an image on a sheet based on an image forming condition; an image reader configured to read an image for adjustment of the image forming condition, which is formed on the sheet; and a controller configured to control, in a case of a job for which printing of the image for adjustment is set, the image forming unit to form the image for adjustment on the sheet, and generate a correction value for the image forming condition based on a reading result of the image for adjustment, which has been obtained by the image reader, to thereby adjust the image forming condition based on the correction value.

An image forming apparatus includes an image forming unit to form an image based on an image forming condition; a sensor to measure a measurement image formed by the image forming unit; and a controller to obtain information correlated with a change in density of an image to be formed by the image forming unit, control the sensor to measure the measurement image, determine first data related to density of the image to be formed by the image forming unit, determine, based on a result of measuring the measurement image, second data related to density of the image to be formed by the image forming unit, and generate the image forming condition based on a weighted average of the first data and the second data.

An image forming apparatus includes: an image carrier to which a lubricant is applied; a developing device that develops an electrostatic latent image carried on the image carrier with toner, and includes a casing accommodating a toner-containing developer and a developing sleeve supplying the image carrier with the toner contained in the developer accommodated in the casing; and a hardware processor that detects information indicating a state of lubricant adhesion to the developing sleeve, and performs, based on a result of the detection by the hardware processor, a lubricant removing operation as an operation for removing the lubricant adhering to the developing sleeve.

An image forming apparatus includes a controller configured to control a first image forming unit such that while a plurality of images are being sequentially formed, a first pattern image is formed in a first sheet-to-sheet area between a first black image and a second black image among the plurality of images on a first photosensitive body, and control the second image forming unit such that while the plurality of images is being sequentially formed, a second pattern image are formed in a second sheet-to-sheet area between a first color image and a second color image among the plurality of images on a second photosensitive body. The first sheet-to-sheet area in a case where the first pattern image is formed without the second pattern image being formed is narrower than the first sheet-to-sheet area in a case where the first pattern image and the second pattern image are formed.

An image forming apparatus includes an image bearing member, a transfer roller, a power feeding rotary member, and a controller. The controller is configured to execute the cleaning mode such that a period in which the cleaning mode is executed comprises a first application period during which a reverse polarity bias having a polarity reverse to that of the transfer bias is continuously applied to the power feeding rotary member, and a second application period during which a same polarity bias having a same polarity with that of the transfer bias is continuously applied to the power feeding rotary member.

An image forming apparatus includes one or more developing units, a detector, a voltage application unit, one or more exposure units, an image conveying member, one or more primary transfer members, a sensor, and a setting unit. The one or more developing units each include a photosensitive member and a developing member. The detector detects the one or more developing units. The voltage application unit applies a development voltage to the developing member. The one or more exposure units each expose the photosensitive member. The one or more primary transfer members each transfer, onto the image conveying member, a developer image. The sensor detects a developer amount on the image conveying member. The setting unit acquires developing unit information on a detection result from the detector, and sets a first-developing-unit development voltage, first-developing-unit exposure energy, or both on a detection result from the sensor and the developing unit information.