I have both the 50mm 1.8D and 35mm 1.8D. I use my 50mm more but I do mostly outdoor work. Both are good lenses. If I were in your shoes I'd keep in mind that the 50mm is roughly 59% of the 85mm from field of view perspective and the 35mm is 41%. In a game as quick as basketball you might find that the 35mm will give you more latitude from a depth of field perspective and capture more clear/in-focus images than the 50mm.
>I'd keep in mind that the 50mm is roughly 59% of >the 85mm from field of view perspective and the 35mm is 41%.
I know what you mean, but that sounds backwards to me - your percentages relate to the focal lengths. The angles of view obviously increase as focal length reduces. The (rounded) horizontal angles of view on a DX camera are as follows:
Terry - It depends on where you'll be shooting from. I shoot for a small weekly newspaper and there can pretty much roam the floor outside the boundaries. I shoot basketball a lot, from almost immediately under the basket, most often using a 24-70mm f2.8 Nikkor. This brings a sense of immediacy to the photos, almost like the viewer is in the action -- sample attached. I think the 35mm will serve with best there, especially on a DX body, as I see that many of my photos are shot at 50mm and shorter. The 35mm will be a much like a 50 on an FX body.
In my case, the 50 f/1.8D is slower - this will vary from camera to camera, though, as the 50 f/1.8D uses the body's AF motor, while the 35 f/1.8G DX uses an AF-S motor built in - on my N80, the 35 is significantly faster.
Both, however, are fast enough to track basketball, and I've never had a problem with speed of the 35, so long as there's enough light for the AF sensors.
I'd also take a look at the AF-S 50 f/1.8G, which focuses much faster than both of them. Compared to the 50 f/1.8D, it has less flare under harsh indoor lighting conditions (I own both of them). They're both sharp, but the newer f/1.8G is slightly sharper IME - although on a D200 the difference is likely negligible.
I've used all three for basketball from under the basket: AFS 35 f1.8G, AFS 50 f1.8G, and AF 50 f1.8D. This is my opinion:
I have kept the 35 and the 50mm AFS lenses and sold my older 50 AFD. The 50 AFD autofocuses too slow on my D7000. It simply cannot lock-on fast enough or track focus on players especially when they are moving toward the camera. The newer AFS 50 and the AFS 35, while not speed demons, are much faster than the older AFD version, and are adequate.
I use both regularly for basketball, but I find that I get the majority of my keepers with the 50mm. For shots right under the rim, the 35 is great (especially for high school), but move 10 feet or more into the court, and the 35 is just too short. And, forget anything further out than that. The D7000 simply doesn't have the resolution and noise control for cropping to fill the frame from too far out with the 35mm.
I also have the newer AFS 85mm f1.8G, which I use when I move out to the corners and sidelines to shoot the guards and a little defense. The older AFD version of that lens was painfully slow to AF-lock and track (which is why I replaced it). After one season with the new lens, I'm still learning how to use it effectively for hoops. I find it much more limited and challenging to use than the shorter lenses.
Some of my limitations with these lenses may be the D7000. Indoor basketball is extremely challenging to shoot. High ISO's, low light. It really taxes the AF system on these amateur cameras. I still have my old 85mm AFD, and I am toying with the idea of packaging it with my D7000, and trading both for a new D7100, with the professional 51 point AF system (and the bonus of more resolution for cropping). I'm guessing that will make a far bigger difference than any one of these particular lenses in terms of generating more sharp in focus keepers.