DX lens recommendations please

[astroNikon]

I think the 17-70 is your best bet

Hi, yes I have seen these for a good price. Do you have one? I can't seem to find out online at what point the widest aperture changes. Is it 2.8 til 50mm and then it changes to 4? Anyone know this? I also wonder how less sharp it is compared to the 17-50? Is it significant?

Nope, but mathematically it seems to fit on the low end.
I have a Nikon 24-85/2.8-4.0 that I used on a d7000 and now a d600.

variable aperture lenses vary the entire focal range not just at certain points.

For instance on my 24-85/2.8-4.0 the camera registers this:
24/2.8
28/3
35/3.2
50/3.5
70/4
85/4

 

[Ido]

You mentioned being interested in lenses whose focal length(s) fall in the 24–100 mm range, more or less. Is that referring to the 35mm-equivalent, or the actual focal length of the lens? I had guessed you meant the latter when I read your post, but upon reading the comments, I see most are recommending lenses that fit that range in 35mm-equivalence.

If my initial assumption was correct, then consider the Tamron 28-75mm f/2.8. All I’ve ever heard about this lens has been positive, and at its current asking price—you can easily find used ones for $200—it’s a real bargain.
If you wish to trade a stop of maximum aperture for a longer telephoto reach, look for a used Sigma 24-105mm f/4 or Nikon 24-120mm f/4. Both are quite expensive brand new (~$800 for the Sigma, over a grand for the Nikon), but used you may find them at a more affordable price.

If you are referring to the 35mm-equivalent focal lengths for field of view, then I agree with the Sigma 17-70mm f/2.8-4 recommendation. An even better option is the new Nikon 16-80mm f/2.8-4, but given it’s a new lens that goes for over $1,000, I doubt you’ll find it at a suitable price for you.

Cropping a 35mm lens won't make it compress facial features like a 50mm lens would or
people would shoot portraits with 50mpix cameras using the 24mm 1.4 lens and "crop in"
to 200mm.. hey.. saves you the 70-200 2.8 money!

Well, this is actually wrong. It’s a common misconception, that I remember having myself, that the cause for the “compression” is focal length, and that a longer focal length makes facial features less distorted. That is absolutely not true.
That “compression” is caused by what’s called “perspective distortion.” It depends solely on how you point the camera: how close/far you are to the subject; whether you’re shooting at eye-level, or from above or below; etc. You could use any focal length you want, and if you crop all images to the same framing, they will look more or less identical—barring differences in resolution and optical flaws of the lens itself, such as barrel/pincushion distortion (which have nothing to do with the focal length; not directly, at least).

 

[DB_Cro]

I meant doing the exact same framing with the 35 vs 50, obviously, zooming with your feet.
This will not result in the same image.

 

[Ido]

I meant doing the exact same framing with the 35 vs 50, obviously, zooming with your feet.
This will not result in the same image.

Then what’s this about? …

Cropping a 35mm lens won't make it compress facial features like a 50mm lens would

 

[DB_Cro]

That too.

 

[Warhorse]

You can get a Nikon 18-105mm for $400 or less if you shop around