I enjoyed reading this book; it has confirmed many of the things that I already knew and sharpened my grasp of several topics.However, I think it takes an over-complicated approach to choosing scan resolution. Here's my approach. First, do a test scan as follows: snapshots at 400 dpi, studio portraits at 1200 dpi, and 35 mm slides at 2400 dpi.If you are scanning a roll of film, scan the first snapshot at 400 dpi, then zoom in until you begin to see loss of detail. If this is caused by blurriness in the snapshot, then your 400 dpi scan resolution is capturing all the detail possible. You might lower the scan resolution to 300 dpi, then 'way in on this new image until blurriness occurs. In any case, if blurriness occurs because you are seeing square pixels, raise the scan resolution and try again. I find that 400 dpi works OK for handheld snapshots.Studio portraits are typically much more detailed. I'd go for 1200 dpi. And 35mm slides (which are actually 36mmX24mm) do well at 2400 dpi (taken with a handheld camera).Doing this "zoom test" gives you a higher resolution digital image to work with. Later, you can downsample if needed.You won't want to scan at a modest, space-saving resolution only to find later that you want to crop a detail (like one person's face in a group photo) and find that facial details are pixelated.Processor speeds are fast, and storage is cheap. Use it.
