just to save any confusion, the "dots per inch" resolution that you're
working with while building and editing your image can be considered a
little like the zoom level when you're working with RGB. More dots per
inch is very much like more pixels per inch, it means you're more zoomed
out and looking at a smaller sharper image.
This need not bear any relationship to the dpi setting when you screen
your print ready files. Unless you're using default settings and letting
the software figure it out itself.
It's not unreasonable to work with 600 dpi images for a sharper
resolution across the page, then apply a 133 dpi screen when you're
finished. It actually helps the quality if the dpi setting of your image
is not a factor of the dpi setting for your screen. So if you work at
399 dpi then use a 133 dpi screen you may as well just use the default
Going the other way can be a little tragic though.