A method for correcting tone-level non-uniformities in a digital printing system includes printing a test target having a set of uniform test patches. The printed test target is automatically analyzed to determine tone-level errors as a function of cross-track position for each of the test patches. A tone-level correction function is determined and represented using a set of one-dimensional feature vectors which specifies tone-level corrections as a function of cross-track position, pixel value and time. Corrected image data is determined by using the tone-level correction function to determine a tone-level correction value for each image pixel responsive to the input pixel value, cross-track position and time. The corrected image data is printed using the digital printing system to provide a printed image with reduced tone-level errors.

An image forming apparatus includes a first display portion to display a ratio of an amount of toner accommodated in the developer container to a maximum amount of toner that the developer container is capable of accommodating, and a controller to, in a case where a replenishment operation, in which toner is supplied from the replenishment container to the replenishment port, is performed when a second display portion is in a second state, switch the second display portion from the second state to a first state and perform a display processing of displaying, on the first display portion, the ratio corresponding to an amount of toner accommodated in the developer container after the replenishment operation.

An image forming apparatus includes an apparatus body, a cartridge attachable to and detachable from the apparatus body, a replenishment restriction portion configured to switch between a restricting state in which toner replenishment through a replenishment port is restricted and an allowing state in which toner replenishment through the replenishment port is allowed, a toner remainder amount detection portion, and a controller. The controller is configured to, when the replenishment container is attached to the replenishment port, maintain the replenishment restriction portion in the restricting state in a case where a second printable sheet number is larger than a first printable sheet number, with the first printable sheet number being obtained from a lifetime of the cartridge, and the second printable sheet number being obtained from a sum of the amount of toner accommodated in the developer container and an amount of toner accommodated in the replenishment container.

An image forming apparatus includes a photosensitive member; an exposure portion configured to expose the photosensitive member to light depending on image information to form a latent image on the photosensitive member; a developing portion configured to develop the latent image into a toner image with toner; and a transfer portion configured to transfer the toner image from the photosensitive member onto a recording material. The image forming apparatus changes a surface movement speed of the photosensitive member at timing prior to predetermined timing, when a moving speed of a recording material at the transfer portion changes, by a predetermined time.

A moisture detecting apparatus includes: a light emitting unit including a first light source configured to emit light having a first wavelength as a peak wavelength, and a second light source configured to emit light having a second wavelength as a peak wavelength; a detecting unit configured to detect a first detection value indicating an extent to which the light emitted from the first light source is transmitted through a recording material, and a second detection value indicating an extent to which the light emitted by the second light source is transmitted through the recording material, based on a light receiving result of a light receiving unit; and a determination unit configured to determine a value related to a moisture content of the recording material based on the first detection value and the second detection value.

An image forming device includes an image forming unit, a conveying unit, a first image detecting unit, a second image detecting unit, and a controller, wherein the controller includes a detecting unit correcting mode in which the first image detecting unit is corrected by using an image detection result by the second image detecting unit, and in the detecting unit correcting mode, a transfer paper conveying speed at the time of image reading by the second image detecting unit is changed to the transfer paper conveying speed different from a normal transfer paper conveying speed at the time of image formation and the first image detecting unit is corrected based on read results of the same image by the first and second image detecting units.

The present invention is to provide a binding processing apparatus that prevents easy unbinding regardless of thickness of a sheet bundle to be bound and that lessens influence of damage on sheets. In the present sheet binding processing apparatus, a pair of pressurizing faces for pressure-nipping a sheet bundle are formed to have tooth forms each having a convex shape and a concave shape, the tooth forms being engaged with each other along a predetermined tooth width, and the tooth forms are shaped so that an engagement depth between a tooth top and a tooth root is varied along a tooth width direction toward a sheet end edge.

The image forming apparatus has a fixing belt, a heater, a switch, a breaker, and a controller. The fixing belt is configured to circulate. The fixing belt is positioned to contact a sheet to which a toner image is transferred. The heater is configured to heat the fixing belt and thereby heat the toner image via the fixing belt. The switch is configured to selectively supply the heater with electric power provided by a power source. The breaker is connected between the power source and the switch. The breaker is operable in an OFF state and an ON state. The controller is configured to (i) switch the breaker to the OFF state from the ON state and (ii) maintain the breaker in the OFF state when (i) the state of the breaker is in the OFF state and (ii) circulation of the fixing belt is stopped.

An image forming apparatus includes an image formation unit, a detection unit, a storage unit, and a control unit. When the detection unit outputs a second output value when a second recording material, which is different from a first recording material is detected, in a state where the storage unit stores a first output value output by the detection unit upon detection of the first recording material, the control unit controls an image forming condition based on at least the first output value if a differential value between the first output value and the second output value is smaller than a predetermined threshold value and controls the image forming condition based on the second output value without using the first output value if the differential value is greater than the predetermined threshold value.

An image heating apparatus includes an endless belt, a temperature raising portion, a first detecting portion configured to detect the temperature of the endless belt at a widthwise central portion, a controller configured to control energization to the temperature raising portion depending on an output of the first detecting portion, a second detecting portion configured to detect the temperature of the endless belt at a widthwise one end portion, an air blowing portion configured to blow air depending on an output of the second detecting portion to cool the widthwise one end portion of the endless belt, and a discriminating portion configured to discriminate whether or not the endless belt is broken on the basis of the output of the second detecting portion when the air blowing portion is operated while effecting the energization to the temperature raising portion.