According to an embodiment, an image forming apparatus executes, if an execution frequency setting of positional deviation correction in setting information is equal to or larger than a reference value, the positional deviation correction by using an image pattern for positional deviation measurement that is formed to be equal to or larger than one cycle of a transfer belt. Further, the image forming apparatus executes, if the execution frequency setting of the positional deviation correction in the setting information is less than the reference value, the positional deviation correction by using an image pattern for positional deviation measurement that is formed to be smaller than one cycle of the transfer belt.

According to an embodiment, an image forming apparatus executes, if an execution frequency setting of positional deviation correction in setting information is equal to or larger than a reference value, the positional deviation correction by using an image pattern for positional deviation measurement that is formed to be equal to or larger than one cycle of a transfer belt. Further, the image forming apparatus executes, if the execution frequency setting of the positional deviation correction in the setting information is less than the reference value, the positional deviation correction by using an image pattern for positional deviation measurement that is formed to be smaller than one cycle of the transfer belt.

An image forming apparatus includes a light emitter; a photoconductor to form a latent image on a surface of the photoconductor; a deflector to deflect light at a write start timing; an optical sensor; and circuitry. The optical sensor detects the scanning light scanning, with one of multiple sensitivities. The circuitry adjusts a light intensity of the emitted light and the write start timing based on the detection signal; switches from the one of multiple sensitivities to other of multiple sensitivities or from the other of multiple sensitivities to the one of multiple sensitivities based on the light intensity adjusted; and determines whether to perform a color misregistration correction based on a shift in the write start timing caused by a switch from the one of multiple sensitivities to the other of multiple sensitivities or from the other of multiple sensitivities to the one of multiple sensitivities.

According to an embodiment, an image forming apparatus executes, if an execution frequency setting of positional deviation correction in setting information is equal to or larger than a reference value, the positional deviation correction by using an image pattern for positional deviation measurement that is formed to be equal to or larger than one cycle of a transfer belt. Further, the image forming apparatus executes, if the execution frequency setting of the positional deviation correction in the setting information is less than the reference value, the positional deviation correction by using an image pattern for positional deviation measurement that is formed to be smaller than one cycle of the transfer belt.

An image forming apparatus includes a hardware processor that functions as a registration corrector and an information presenter; and a first storage. With a registration sensor, the registration corrector detects a formation manner of a registration pattern of each color formed on the intermediate transfer belt, and corrects a color shift amount of each color based on a detection result. The first storage stores measurement data of the color shift amount of each color measured by the registration corrector. The information presenter presents operation assistance information to the operator based on the measurement data stored in the first storage when the registration corrector indicates an error.

An image forming apparatus includes: a control unit configured to form, onto an image carrier, a detection pattern including a first image group including a plurality of first images and a second image group including a plurality of second images, and determine a color misregistration amount in a rotational direction and a width direction orthogonal to the rotational direction based on a detection result of the detection pattern. The detection pattern includes a plurality of basic patterns arranged at a first interval in the rotational direction, and each of the plurality of basic patterns includes the first image group and the second image group arranged at a second interval in the rotational direction, and the first image group and the second image group arranged at a third interval different from the second interval in the rotational direction.