Yeah, the idea is that you get back from your shoot with hundreds of photos, you import them into Lightroom/Aperture where you can scroll through them all easily, selecting one and quickly rotating/cropping, or correcting exposure and white balance, then you move onto the next, rating each as you go whilst discarding some (except they just get hidden from the default view).
Once you've pruned hundreds of shots down to a dozen or so you end up with a nice library of your best shots. Then, if you want to something fancy with one of them, you fire up Photoshop.
Once you've pruned hundreds of shots down to a dozen or so you end up with a nice library of your best shots. Then, if you want to something fancy with one of them, you fire up Photoshop.