Is the 85mm 1.8g fine for portraits for a DX body?
I have a nikon D7000, I mainly do portraits and I'm just wondering is 127mm okay for portraits (mainly outdoor) since I'm using it on a DX body
It will depend on how much of the subject you want to appear in the picture and how far you will be from your subject. 85mm on a DX will approximately give you a head and chest shot from about 15ft. You definitely can't use your bedroom voice to give instructions to your model but it will be great for shooting across the pool if you like to get the whole body with some water in the foreground.
It will be great.
I like poo
Keerok is 100% correct
Directing people while shooting portraits is very important, so that is why the 50 mm f/1.8 lens is so popular lens used by portrait photographers when using a DX body. You are close enough using a nice medium telephoto lens like a 50 mm lens to speak quietly to your subject.
I use a similar combination of EF85mm f/1.8 on a Canon 70D.
The 85mm lens is very good for tight face shots and head and shoulders without having the camera in the model's face. After that you start to get rather a long way away. That is very good for informal work where you can keep your distance and not intrude (eg children playing, people at work) but it does make communication difficult for more formal work and also stretches the range of your flash. That is where a 50mm f/1.8 lens takes over.
On a 35mm film camera or full-frame DSLR a focal length of 85mm to 105mm has long been considered an ideal focal length for portraits. That's why so many people recommend a 50mm lens on a crop-sensor (DX) DSLR. It gives you a better working distance without having to resort to yelling instructions to your model.
On your DX camera, an 85mm will be equivalent to 127.5mm on a full frame camera.
Yes it will do for portraits, but it's not the best choice for a cropped sensor camera. It's going to be a bit tight, so you will need to stand quite some distance from your subject.
It would be better to have a look at a 50mm f/1.8 or f/1.4 (75mm full frame equivalent).
For outdoors, with lots of space available, 85mm is ok on crop-frame for portraits. Personally I would find the need for 50mm or 60mm indoors, in smaller spaces.
I would buy a 50mm, if I did not already have a 50mm f1.4.