I'm pretty new to photography, I picked up my D 5100 a couple months back. With only the kit 18-55mm lens. Now I am planning to upgrade this one..
I've heard great things about the Nikkor 35 mm f/1.8G DX including, fantastic performance in low-light, a great first prime lens, and generally being a great lens for newbies and pros alike.
Now, the new Nikkor 40 mm f/2.8G DX micro lens caught my attention, the versatility and range of different shots it can take that are on sample on the official nikon site has got me thinking that this lens could also meets my needs. Although Nikkor 50 mm f/1.8G FX lens is on my consideration.
I take my camera with me pretty much everywhere. Therefore, I'm looking for a lens that can do some general photography work. The price won't be an issue. I'm leaning towards the 35 mm and 50 mm because I do have some difficulty with low light conditions, however the 40 mm looks great for food shots or landscape shots. My primary need is to get the sharpest portraiture. I’ve heard that the prime lenses having macro abilities do this job well. I don’t know whether thing is true or not.
However my question:- which one would you recommend as a first lens for sharpest portraiture photo with decent bokeh?
35 mm f/1.8G or 40 mm f/2.8 micro or 50 mm f/1.8G ????
First, I hope you know about the "crop factor". In your camera it's "1.5" because you have a DX sensor (aka APS-C on canoneze). This means that compared to a FX sensor, the angle of view is decreased by that factor, which translates in an apparent "zoom" effect by the same factor.
For example, with a 50mm lens, you will take similar picture as with a 50mm*1.5 = 75mm lens on a FX body.
I recommend to check what the professional portrait photographers use. They use FX bodies and 70-200mm range lenses. That means that if you want to get similar pictures with your DX body, you should use lens range between 50-130mm. So 50mm is at the lower end.
So I would recommend you the 50mm f/1.8G if you want to use it exclusively for portrait work. Of course the f/1.4 version is much better but several times more expensive, and I wouldn't throw that much money, especially since you said you're new to photography.
Also the 40mm is nice, being also a Micro (macro) lens, which opens the possibility for you to take a whole range of other kind of pictures.
I am offering you this advice, because I had the exact same problem as you (I have a very similar body, the D5300). Two weeks ago I decided to buy the 60mm f/2 Macro from Tamron.
Word of caution: Because of the fact that on your camera a 50mm lens zooms like a 75mm lens on a FX body, you should take into consideration the fact that you need to be around 2m away from your subject for a standard portrait (head to bustline).
Best way to experiment, set your kit lens to 35, 40 and 50mm equivalent and shoot some portraits. This way you can see which lenght is more suitable for your needs.