We interviewed Leif from SignWarehouse Product Support to get his tips on reducing the DPI on images without losing print integrity. Here are his takeaways:
"When dealing with huge or highly detailed raster images, oftentimes the “File Size” (the amount of data being transferred digitally) is a large number. This is a very common problem that causes new printer owners to have their prints stop in the middle or the prints become discolored.
"Here is an example of a raster image I sent to the production manager to show the file size. For most of my prints I try to shoot for 1000-5000k. We are going to lower the DPI.
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First, with your file selected, go do File then Export
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"Next, name your file, select the save type as PDF, and make sure Suppress Options is unchecked
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"Then make sure the scale is set to Full Size. Check the box to Downsample bitmaps, then lower the DPI.
"The DPI starts at 300 by default, but I prefer to divide by 2, until I find a DPI that performs well on the printer.
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"Now back in Production Manager, go to your printer and Add Job. Add the file you just exported.
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"Notice how at the same physical size, our file size is a lot smaller?
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"Those are my tips for reducing the DPI for images. Hope they help you!"