I have a Nikon D5500 (dx body). People are raving about the 85mm 1.8g.( fx & magnifies by 1.5.) Am I better off getting the fx lense 50mm?

I have a Nikon D5500 (dx body). People are raving about the 85mm 1.8g.( fx & magnifies by 1.5.) Am I better off getting the fx lense 50mm? - 1

Bite the bullet you have to have both, sorry.

For what purpose?

The focal length of the lens you choose for your kit is totally based upon your needs as a photographer.

The least used lens in my kit is the 50 mm. I use an 85 mm or 105 mm lens when shooting portraits. I can use the 85 mm on both my DX and FX cameras

What do you need the lens for? Portraits? You'll get the same shot with either lens but will have to stay close with the 50mm and shoot farther with the 85mm. If you are after an all-around lens then the 18-55mm kit lens should do. If you want to stick to a prime lens then the 35mm should be it.

For portraits on crop-frame 50mm or 60mm is excellent, 85mm too long sometimes. 85mm is equivalent to 130mm on full-fame.

Maybe get 60mm macro for a dual-purpose lens.

I have 85mm, 50mm and 35mm prime lenses. They get used in reverse order of frequency. IOW, I use my 35mm much more often than the other two put together. But maybe you have a need for a longer lens, such as doing macro photography using an extender.

First, you do not mention anything about what you plan on doing with the lens. This alone makes it impossible to answer your question.

If you need the light gathering capability that the 85mm f/1.8G provides, and it's focal length is what you need, then go for it. If you're only interested in the lens to create shallow depth of field, then save your money and go with a 50mm f/1.8. If it's for portraiture and you already have an f/2.8 zoom, then you may find it useful sometimes. If you don't already have an f/2.8 zoom like a 24-75, then I would strongly suggest going with a standard zoom first. The versatility that a zoom lens provides will almost always outweigh the usefulness of the shallow depth of field look that an 85mm f/1.8 provides. Most of the time when shooting at an aperture larger than f/2.8, the depth of field is so shallow that it is a huge challenge to get the subjects/eyes in focus. Compare that shot to one taken at f/2.8 or f/4 and it's going to be a lot easier to get a technically well done image.

Technically speaking there's a difference in the amount of blur that f/1.8 and f/4 produce, but at some point you'll have to decide if it's worth the hassle to get a blurrier background when f/4 is blurry enough. With this in mind, I would recommend that you get an f/2.8 zoom which will afford you a good amount of versatility over a prime.

And if you want an even better 85 than the Nikon, Sigma's 85mm Art lens is better in sharpness charts & bokeh comparisons on photozone.de

Photographers, for the most part, are creative and make excellent use of lenses' (yes, possessive plural) versatility. Make up your mind, do you NEED the lenses or do you simply WANT the lenses? You haven't specified what you "need" the lenses for.

IF you simply WANT to have these lenses, consider checking out the Used Camera/Lens Dept at KEH.com and B&H Photo (NYC).

For practical reasons, if you have the f/2.8 zoom lens… You can do without the prime lenses, if you're creative enough and know how to take advantage of lenses' versatility. IF, however, you only have the regular kit zoom lens, 18-55mm (or whatever) f/3.5… LEARN to use that, work on your creativity and get around the supposed pitfalls you THINK you have with it. But if you're a lens and gadget COLLECTOR, then it's a totally different matter, isn't it? BTW, you have a very nice camera… No, not "nice," but great!