Reply To: InDesign/Prepress Myths

@Raphael: You have unfortunately fallen prey to the oldest myth of them all: That scanning at a higher resolution is always better. Like in the health care debate, where some folks erroneously believe that more trips to the doctor or hospital is always better. Not so.

If you scan that map at 1200 dpi, what will happen at print time? Either InDesign will downsample it to a lower resolution or the printer will (depending on your settings). When that happens, it throws away data in a non-intelligent manner, and your image just gets blurrier. Then, if you're printing with halftones, the image gets “downsampled” again in the form of being split up into halftone spots.

I have no problem with you scanning it at 1200 ppi for archival purposes! But placing a 1200 ppi image into InDesign doesn't help, it hurts. 

(You also discount the issue of file size. A 5 x 7 cmyk image at 225 ppi is about 6.5 mb. Increasing it to 300 ppi raises the file size to 12 mb. If you use 1200 ppi, you suddenly have a 192 mb image to play with. That's 185 Mb of wasted data, if you're printing a magazine at 150 lpi. Ten of those images is over a gigabyte of wasted data, of course. Who cares? Disk size, file transfer time, print speeds, pdf creation time… waste not, want not.)