Abstract: In one example, a print zone heater includes a structure defining a plenum, a heating element, a fan to move air over the heating element into the plenum, and a conduit from the plenum to carry heated air into the print zone.

Abstract: A method of printing includes identifying vertical edges in a halftone image. The method also includes determining whether a lightness of color of a first predetermined area to a left side of a respective vertical edge is substantially equal to, less than, or greater than the lightness of color of a second predetermined area to a right side of the respective vertical edge. The method also includes categorizing respective vertical edges left vertical edges, right vertical edges, and neutral vertical edges to prioritize a print direction thereof.

Abstract: A printer control section arranged to control a printhead, is operable to cause the printhead to: perform a plurality of passes over a swath of a print medium, the plurality of passes including first and second treatment passes; apply treatment to the print medium in each of the treatment passes, the treatment in each treatment pass being applied according to a respective treatment mask, wherein each treatment mask indicates a corresponding set of pixels to which the treatment may be applied in a pass to which the treatment mask is applied, the treatment mask having a weight indicative of the proportion of pixels in the corresponding set of pixels, and the treatment masks of the first and second passes are such that a weight of the first treatment mask is different from a weight of the second treatment mask.

Abstract: A printing system comprises a processor to obtain image data comprising first image data defining a first color plane of the image and comprising second image data defining a second color plane of the image. The processor is to manipulate the image data such that the second color plane is shifted relative to the first color plane in a media axis direction of a printer. The printing system comprises a printer to print the manipulated image data with the printer.

Abstract: Provided in one example is a printing system. The system includes a printing zone including a platen (50). The system includes a drive to move a medium (58) through the printing zone. The system includes a suction force generator (78) to generate a suction force to hold down the medium onto the platen while the drive moves the medium through the printing zone. The system includes a sensor (52) to monitor the movement of the medium through the printing zone in a medium advance direction. The system includes a controller to determine that the suction force generated by the suction source generator is insufficient based on an output of the sensor.

Abstract: In one example, a method for wiping the face of a printhead includes wiping across the face of the printhead and then wiping along the face of the printhead with a web of cleaning material. In another example, a wiper for wiping a face of a printhead includes a rotatable shaft having an axis of rotation and a helical blade affixed to the shaft. The helical blade is simultaneously rotatable on the shaft against the face of the printhead and translatable along the face of the printhead in a direction parallel to the axis of rotation.

Abstract: A method is described in which a first color is detected at a user-selected arbitrary position of a first print; a second color is detected at a user-selected arbitrary position of a second print printed by a printer; a color difference between the first color and the second color is determined; and settings of the printer are changed to reduce the color difference in further prints printed by the printer.

Abstract: Examples associated with drop velocity aberrancy detection are disclosed. One example includes firing ink through nozzles of a print-head past sensors to identify drop velocities of the nozzles. A target drop velocity is selected based on the drop velocities of the nozzles. An aberrant nozzles is detected when a nozzle has a drop velocity that deviates from the target drop velocity by a selected threshold. The aberrant nozzle is deactivated, and a good nozzle that will travel over locations traversed by the aberrant nozzle is configured to print portions of a job that would have been printed by the aberrant nozzle.

Abstract: A drive signal may be determined to drive a printhead to a series of target temperatures during respective portions of a print pass by the printhead. Each of the target temperatures may be the greater of a temperature of the printhead caused by printing a quantity of printing fluid to be printed during the respective portion and a predetermined threshold temperature. A drive signal may be provided to warm the printhead to the series of target temperatures during the respective portions of the print pass.

Abstract: According to one example there is provided an accessory for a printing system. The accessory comprises a cylindrical core on which a web of media may be wound, and a flexible sheet having a first end attached to the core and a second free end opposite the first end having a media connector attached thereto, the media connector to connect a free end of a web of media thereto.

Abstract: A method for controlling the amount of printing fluid deposited by a printhead for a plurality of passes of a swath width of a printing process is described. The printing process may include periodic servicing of the printhead. The method may include determining an amount of printing fluid to be deposited for each pass of the swath width; identifying which pass of the swath width servicing is to occur; and reducing the determined amount of printing fluid deposited during a first pass immediately following servicing of the printhead.

Abstract: In some examples, a method includes, in response to a fluid firing unit being operated according to a normal printing mode, applying a first voltage to the fluid firing unit to fire the fluid firing unit during a printing operation. The method further includes determining, using a sensor, whether a predetermined condition is met, and in response to determining that the predetermined condition is met, operating the fluid firing unit according to a recovery mode in which a second voltage higher than the first voltage is applied to the fluid firing unit to clean the fluid firing unit.

Abstract: A method of printing a pattern from at least two rows of fluid ejection nozzles, said nozzles ejecting a first fluid in a multi-pass printing mode, the method comprising: dividing the pattern to be printed between the rows of fluid ejection nozzles; applying masks to the rows of fluid ejection nozzles for printing with selected nozzles of each of the rows of fluid ejection nozzles during each pass; wherein a first mask for printing from a first row of fluid ejection nozzles during an n-th pass is different from a second mask for printing from a second row of fluid ejection nozzles during said n-th pass.

Abstract: In an embodiment, a method of maintaining nozzles in a print-ready condition includes determining image content to be printed in an upcoming print swath, and for each ink color present within the image content, constructing an inked portion of an associated spit bar adjacent to the upcoming print swath to include the present ink color. For each ink color not present within the image content, an empty portion of an associated spit bar is constructed adjacent to the upcoming print swath.

Abstract: Example implementations relate to color compensation. Some examples may print a calibration target background on a non-opaque media. The calibration target background may have a color that increases a dynamic range of a set of color measurements of a calibration target foreground. Some examples may print the calibration target foreground over the calibration target background. Additionally, some examples may measure an optical density of the calibration target foreground with a reflective sensor and may calibrate a printer based on the measured optical density.

Abstract: A drive signal may be determined to drive a printhead to a series of target temperatures during respective portions of a print pass by the printhead. Each of the target temperatures may be the greater of a temperature of the printhead caused by printing a quantity of printing fluid to be printed during the respective portion and a predetermined threshold temperature. A drive signal may be provided to warm the printhead to the series of target temperatures during the respective portions of the print pass.

Abstract: The present disclosure discloses a method implemented by a printer to control a fluid firing unit of a printhead, when said printhead is coupled to the printer, to operate according to any one of a normal printing mode and a recovery mode. According to the method, if the fluid firing unit is operated according to the normal printing mode, a first voltage is applied to the fluid firing unit to fire the fluid firing unit during a printing operation; and if the fluid firing unit is operated according to the recovery mode, a second voltage higher than the first voltage is applied to the fluid firing unit to clean the fluid firing unit.

Abstract: In one example, a method for wiping the face of a printhead includes wiping across the face of the printhead and then wiping along the face of the printhead with a web of cleaning material. In another example, a wiper for wiping a face of a printhead includes a rotatable shaft having an axis of rotation and a helical blade affixed to the shaft. The helical blade is simultaneously rotatable on the shaft against the face of the printhead and translatable along the face of the printhead in a direction parallel to the axis of rotation.

Abstract: A cleaning module includes an actuator device, a fluid chamber, and a wiper member. The actuator device may enter an activation state based on a movement of at least a portion of the actuator device in response to an engagement with the printhead. The fluid chamber may store and supply fluid to the porous wipe material in response to the activation state of the actuator device. The wiper member may apply pressure to a porous wipe material including the fluid therein to wipe the printhead.

Abstract: Herein, techniques are described for printing an image on a print media by operation of a printhead to eject a print fluid over the print media. In at least some examples, a printhead temperature parameter is acquired, the parameter being indicative of a temperature at the printhead during printing; alignment of the printhead is corrected based on the printhead temperature parameter; printing is performed on the print media via the printhead according to the corrected alignment.