In article , Mayayana
wrote:

| You just have to match it up to the printer. For
| instance, a typical photo should be printed at
| least 300 dpi.
|
| Not on the 'photo' Epsons. They use 360 dpi. It pays to check the dpi
| of the printer you plan to use.

It's just an example. The R2880 here defaults to
1440, but it doesn't have to be used that way.

it's actually 5760x1440 dpi.

You should have read the rest of what I wrote....

| That means to get a 5x7 print you
| need 1500x2100 pixels. It doesn't matter what size
| the image is and what dpi the printer is set for.
| You just need to coordinate the two so that it
| will print the size you intend. 300 dpi will give you
| nicer edges on letters, but I guess that probably
| doesn't matter much.

you should read about printing, in particular, the difference between
dpi and ppi.