In one example of the disclosure, a first print engine is to print a first image in a first area of a web substrate, and is to leave blank a second area of the web substrate. The printed first image includes a set of fiducials 1-n. For each of fiducials 1-n, a fiducial position error is determined based upon a comparison of the detected position and a predicted position for a subject fiducial. A substrate advancement error is calculated based upon an average of the determined fiducial position errors. An insertion point is determined based upon the substrate advancement error. The insertion point is a point at which a second print engine in-line with the first print engine is to begin printing a second image in the second area.

An example printing apparatus is illustrated. The printing apparatus includes a print engine assembly. The print engine assembly further includes a bottom chassis portion. The print engine assembly also includes a top chassis portion. The print engine assembly also includes a print head positioned within the top chassis portion. The print engine assembly also includes a plurality of offset pins coupled to the print head, where the plurality of offset pins abuts the bottom chassis portion, and where the plurality of offset pins enables the print head to be positioned at a predetermined distance from the bottom chassis portion.

An image forming apparatus is provided, including a conveying member configured to convey a long paper along a paper path; an image forming unit which forms an image on the long paper being conveyed by the conveying member along the paper path; an image reading unit which reads a surface of the long paper, the surface having the image formed by the image forming unit; and a color sample member which is arrangeable at a position facing the image reading unit, such that the long paper is conveyed by the conveying member to avoid passing through between the image reading unit and the color sample member. Also included is a switch between a first arrangement in which the image reading unit reads the long paper and a second arrangement in which the image reading unit faces the long paper via the color sample member and reads the color sample member, the switch being made by moving the image reading unit or by moving the color sample member and the conveying member.

Certain examples described herein relate to splice detection. In certain cases, a splice is detected in a web being conveyed towards a transfer member of the printing system. In certain cases, a print frame is identified from a sequence of pending print frames using successive repeat lengths of the sequence and a distance of the splice from the transfer member. The identified print frame is to be transferred from the transfer member across the splice. In certain cases, writing of the identified print frame onto a photo-imaging plate of the printing system is deferred. In certain examples, the web is disengaged from the transfer member following transfer of an image of a print frame preceding the identified print frame. The web is re-engaged with the transfer member so as to transfer an image of the identified print frame to the web from the transfer member after the splice is conveyed beyond the transfer member.

An image forming apparatus includes a supplying unit that supplies a continuous recording material, an image forming unit that forms an image on the recording material supplied from the supplying unit, a fixing unit that fixes the image formed on the recording material by the image forming unit, a collecting unit that collects the recording material having passed through the fixing unit, a detecting device that detects a change in tension of the recording material running between the image forming unit and the fixing unit, and a tension adjusting device that adjusts the tension acting on the recording material such that the change in the tension of the recording material falls within a permissible range if the change in the tension of the recording material that is detected by the detecting device exceeds the predetermined permissible range.

An image formation apparatus according to an embodiment includes: a medium conveyance device that conveys a continuous medium; an image formation unit that forms a developer image on the medium to print on the medium; a used condition detector that detects a used condition of the image formation unit; and a controller that controls the medium controller, the image formation unit, and the used condition detector. When it is determined that the image formation unit comes to a time for replacement during a printing operation, the controller selects whether to continue the printing operation based on the detection by the used condition detector.

A base material processing apparatus includes first and second edge sensors and a displacement amount calculation part. The first edge sensor acquires a first detection result (R1) by detecting the position of an edge of a base material in a width direction at a first detection position. The second edge sensor acquires a second detection result (R2) by detecting the position of the edge of the base material at a second detection position. The displacement amount calculation part calculates the amount of displacement in the position of the base material in the transport direction or the amount of difference in the transporting speed of the base material on the basis of the first and second detection results (R1, R2). Thus, the amount of displacement in the position or the amount of difference in the transporting speed can be detected without depending on images such as register marks.

An image forming apparatus includes a first conveyor, a cutter, a second conveyor, a detection image forming section, a detector, and a controller. The first conveyor conveys a print medium. The cutter cuts the conveyed print medium. The second conveyor conveys, in a first direction, the print medium cut by the cutter. The detection image forming section forms a detection image on the print medium and the second conveyor. The detector detects, at two positions in a second direction, the detection image formed on the print medium or the detection image formed on the second conveyor. The controller varies one or both of a conveying speed of the print medium to be conveyed by the first conveyor and a cutting speed of the print medium to be cut by the cutter, on the basis of a comparison of the detection image detected at the two positions.

A roll-paper printing apparatus includes a paper feeder that feeds roll paper, a printer that forms an image based on a job on the roll paper, an image scanner that scans the image formed on the roll paper, and a reeler that reels the roll paper, and the roll-paper printing apparatus includes a hardware processor that acquires the image scanned by the image scanner and detects an abnormal output in comparison between the image based on the job and the scanned image, and determines whether output of the job continues or stops, in accordance with a previously set condition, wherein, when the roll paper is cut in a passage direction of the roll paper into a plurality of lanes arrayed in a width direction of the roll paper, the hardware processor continues, in a case where the abnormal output is detected on a lane, the output of the job.

An image forming apparatus includes: a conveyer that conveys continuous paper through a conveying path; a detector that detects a mark on the continuous paper conveyed by the conveyer; an image former that is provided on a subsequent stage side of the detector and forms an image on the continuous paper; and a hardware processor that causes the image former to start forming an image according to a position setting for forming an image on the continuous paper using the image former after a mark on the continuous paper is detected, wherein the hardware processor adjusts the position setting on the basis of a start position determined according to an image formation state.