What is usually involved? How much processing is required to have a good final product? If we're talking about a few small adjustments, it's no big deal. On the other end of the spectrum, several hours of tweaking in PS would be a little much and I'd question the capabilities of the camera or operator.
That's entirely up to you, your skills as a photographer, your mastery of Photoshop, and of course, the element of luck.
I doubt I've ever taken a digital photograph that didn't require at least a little work in Photoshop, and can assure you I never worked with a scanned transparency that didn't require at least a certain amount.
I'm a painter who dabbles in photography, so my perspective may be a step or two off the beaten path. It's a rare photographvery rarethat runs the full gamut from true black to nothing at all without suffering losses in the mid-tones. Do you actually want the full gamut? Are the mid-tones too blue? Are the highlights too red?
Once you've got the fundamental stuff squared away, working digitally enables you to start the what-if? process. What if I desaturate the shadows 21% and pump up the blues in the mid-tones? What if I pull back the highlights and do a judicious bit of blurring there to offset the sharpened mid-tones? What if...? Where to sharpen? Where to add contrast? Where to add light?
If you literally read the Photoshop manual from cover to cover a time or two, and invest a few months figuring out what's what in the LAB color space, you'll suddenly discover photographs as taken by cameras are a wonderful starting place.
If you want to do more, there's a brand new world waiting for you. For your sake, I hope you have more sense: it can be enormously addictive.
