Markzware develops FlightCheck electronic preflight application to check Adobe InDesign CS5 and many more file types. Here is a view of upsampling to increase image resolution. This is an area often flagged during electronic preflight to check InDesign and other DTP files:
Image resolution refers to the measurement of the number of squares (called pixels) of color information in an inch. Below is an illustration of how the same image might appear at a different pixel image resolution.
Image Source: Graphics Depot, Inc.
Design guidelines tell how to increase image resolution during electronic preflight. (Preflighting helps to prepare files, such as graphic design color layouts in InDesign CS, for printing.) These design guidelines describe and advise against upsampling to improve image resolution (per the design guidelines section called, “Upsampling in Photoshop to Improve an Image“). The recommendation to increase image resolution with 72 dpi image upsampling to 300 dpi would produce documents of inferior print quality and is not recommended.
Naturally, design guidelines, file preparation manuals and customer service representatives are all great. Nothing will better help you, as a print-buyer, than to check Adobe InDesign CS5 layouts (or Quark, Adobe Illustrator, etc.) during prepress. Prepare Adobe InDesign files for printing with Markzware FlightCheck, before sending them to the printer. The latest version was just released for Macintosh and now FlightCheck can check Adobe CS5 files!
For further information on image resolution, including information on high-resolution and low-resolution for images, see the section of the FlightCheck Manual on Image Resolution. Check out the FlightCheck page for preflight software that will check image resolution.