The optimum scanning resolution for any given size of photograph is shown below.  At best, our eyes can resolve detail as fine as 180 dots per inch, but lets say 200dpi* to be sure.  Scanning above this figure will only add to the file size, not perceived image quality.

This basic rule holds for all occasions where the scanned original and the final print are the same size.

If the final print is to be larger than the scanned original, then you need to scan at more dpi.  Conversely, if the final print is to be smaller than the scanned original, you need to scan at a lower dpi, if the optimum file size is to be maintained.

The following table shows the size of restored prints available from PhotoTec and the resolution you should scan at, in dpi, based on the size of your original.

NB: Please scan all originals in full colour

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*Dots Per Inch. Printers quoting resolutions >1000dpi do so because, in order to represent millions of colours, the printer squirts up to 8 dots superimposed on each other from the coloured ink jets in the print head. This is counted as 1 dot as far as our eyes are concerned, or up to 8 dots if you are a printer manufacturer!