No printing software "sees" centimeters or inches. The dimensions of an
image is in pixels only and this is the only thing the printing software
sees about your image. No inches or centimeters (see my answer to your
message of 5:44AM).
When you print, you must select a size in inches or centimeters. The
software takes the dimensions of your image in pixels and prints the size
you select.
For a very good print, take the dimensions of your image in pixels and
divide by 300 to get an idea of how large a print you can make, if you want
a smaller print than the answer below there is no problem.
So if the dimensions of your image are 5000 x 4000 pixels, you can print at
16.6 x 13.3 inches. You can reduce 300 down to 200 and still get a decent
print of a larger size. Below 200 the quality of the print will deteriorate
pretty quickly.
Faststone will give you the options such as "fit to page" or "specified
size". It will give you a "preview" of how the image will be printed on the
page by your printer.
However, there is another problem that you must solve before you print. You
must fit the aspect ratio of your image to the aspect ratio of the paper
size you select.
The aspect ratio is simply dividing the width by the height of the pixel
dimensions.
In the example above it would be 5000/4000= 1.25.
So if you print on 10 x 8 in. paper size, 10/8= 1.25 and the image will fit
perfectly.
If you print on 6 x 4 in. paper size, 6/4= 1.5. The image will not fit and
Faststone will show you (in the print preview window) how the image will be
automatically cropped to fit the size you selected. If this is not to your
liking. after you open the image with Faststone, use the crop tool. Crop the
image to the paper size you want to use, placing the crop where you want it,
then print using the paper size you cropped the image with. Faststone will
also let you save the cropped image, with no alteration to your original
file. Go with this option since you may want to print at a different size in
the future and you will want to crop the original image.
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