Nikkor 50mm AF-S 50mm f/1.4G or AF 50mm f/1.8G?
For the Nikon D90. I have much experience on cameras but I'm about to buy the Nikon D90 and would like some feedback. I already have the 1.8G, is it even necessary to buy the 1.4? Which difference would it make?
The f/1.4 will get you slightly better image quality, and of course, 2/3 of an extra stop. It also has better autofocus.
As you probably already know, lower-end Nikon cameras don't have the AF motor built into the body, and as the 50mm f/1.8 doesn't have an AF motor in the lens, it becomes a manual focus only lens on the entry-level bodies. So you don't have to worry about that anyway with the D90.
Lens choice, of course, depends on what you're going to shoot. The D90 has a crop factor of 1.5x. That makes the 50mm a workhorse if you shoot lots of portraits. Heck, I use my 50mm for portraits all the time on my full-frame body.
If you have the money and you shoot living targets a lot with your 50mm, I would say it's worth it to upgrade. The better AF will help you get a lot more "keepers" and a lot fewer "no-good" shots due to missed focus. If you don't need the AF, there's probably better things to spend the money on.
I personally shoot with the Canon 50mm f/1.4 and I like it Way better than the 1.8.
Either one will work just fine with your camera
http://www.dxomark.com/...mera2)/485
As you can see, the f/1.8 lens slightly out performs the f/1.4, but just by one point
At this point, you can save some money and buy the f/1.8 lens since both lenses will auto focus on your camera
The AF 50mm f1.8 will be sufficient for your needs. If you don't have a good tripod use the money you would have spent on the AF-S 50mm f1.4G to buy a tripod.