HOW TO.

CHOOSE THE CORRECT SCANNING RESOLUTION
At which resolution should we scan a photograph to get the best print quality on an EPSON Photo printer?

Since the required image resolution is highly dependent on the type of output you choose for presenting your work, it
is best to define your requirements before scanning. This will avoid your image data being too big and will also make
sure your resolution is not too low. It may however mean that at a later stage, when another job comes with different
requirements, you will have to scan and process again.

In cases where you know you will apply a couple of changes to the original, it is wise to make a larger scan, make all
the changes you wish and in addition to the larger file you will keep in storage make another that is just right for your
chosen type of output. This way you will not reduce the print time due to a large amount of "unnecessary" data while
at the same time keeping all options open.

In order to find the correct scan resolution for your job, you can either use the utilities included in your scan program
or use the following tips:

The ideal image resolution range is from 250 to 300 dpi for EPSON Photo printers. 

250/300 dpi is the best resolution for a 20 x 30 cm photo where the viewer distance is very close. In the case of
a larger photo, we usually assume that the viewing distance is equal to the document size. This allows the image
resolution to be smaller, which makes the data file smaller. For example, for a 60 X 80 cm photo, 200 dpi image
resolution is acceptable.

Image resolution must also be modified according to the size of the original. In most cases, the original will be
enlarged. You can easily find out the correct scanning resolution by applying the following formulas :


1. (Size of output ) / (Size of original ) = (Enlargement factor)
2. (Enlargement factor) x (Image resolution) = (Scan resolution)

Please note that the image resolution is not the printer resolution itself. This is because of the way images are
formed by drop-on-demand inkjet printers, like EPSON Stylus printers. Here in principal one pixel can only be either
Cyan, Magenta, Yellow or Black or any other color that is ejected out of the nozzle of your printer. The color is than
mixed by the eye. In your data one pixel can be already the mixed color and contains therefore more data. For this
reason the resolution you need for your files is far lower than the resolution your printer needs for supreme output.

The tables below offer a detailed practical explanation of the above:


Printing photo = < 20 x 30 cm ( A4)
Ideal image resolution = 250 � 300 dpi