What lenses better to use for engagement session?

I have nikon 50mm 1.4 G and 24-85 2.8. I need someone opinion what lenses better to use for engagement session? I'm thinking to rent 24-70 for that instead of 24-85? Is it good idea?

Maybe, but not likely.

The 24-85mm is not a constant f2.8 aperture, where as the 24-70 is. The 24-85 is f2.8 to f4.0, depending where your zoom is set. If you're going to illuminate the engagement shots with flash or lighting, this won't be a big deal, but if you want as blurred background as possible, it may.

I'd stick with primes. Use your 50mm and rent an 85mm f1.4 and maybe a 135mm f2.0 too depending on your location. Shoot wide open, use the shallow focus, (Min.depth of field), and look for bokeh.

I totally disagree with the answer saying to shoot the lenses wide open. If you shoot at such apertures as 1.4 or 1.8 or 2.0, the depth of field is going to be so shallow, that not even all of one face is going to be in focus in many cases, depending on how close you are to the subject and what lens you are using. But at any rate, you are not likely to have both people in focus, and I don't think a couple will be happy with engagement photos when one of them is always out of focus. My advice to you is get in a large enough area where you can use the 50mm lens at all times, and try to keep any background as far in the distance as possible. I would not shoot two people together at anything less than f5.6, maybe even f8. For any close ups of one individual, you can open up the aperture, just be sure and focus precisely on the eye that is closest to you. NO automatic camera focus point selection… EVER.

Your 50mm is good… Maybe pick up a 70-200 f2.8?

It. Important when you mention lenses that you mention when you have a lens that has a variable aperture based on focal lenght like the 24-85 f2.8 it's actually a 24-85 f2.8-4.

So yeah, it's not really equivalent to a 24-70 but for portrait work it will be more than adequate.

I'd use what you already have. I used the 24-85 F/2.8-4 a lot on my film cameras. It is a fine portrait lens on a crop sensor. And f/4 is plenty fast enough for portraits. In fact, unless youare used to shooting at open apertures, you may find it a struggle to get both faces in focus especially in something like and engagement session which usually are shot outside of a studio. So you'll want to stop down a little anyway.