Originally posted by tuco In Lightroom I just cropped the imported image to the size you see. The imaged was scanned at 4000DPI with a size reduction of 2 (averaging 2000DPI and 4000DPI). The scanning software says DPI but I suppose it really is SPI?
Yeah, the second crop I thought looked like 2000. I was just interested in figuring out how small the grain is.
SPI, DPI, PPI all seem to be used interchangeably. I like to use Samples Per Inch for scanning, Pixels Per Inch(300, 360, etc.) for for digital files being sent to print and Dots Per Inch for printing/printers (1440, 2880, etc.). Doesn't really make much difference, it's just a habit.