How much smaller would a DX version be?

Just curious if someone who knows about such things can predict how much smaller a DX version of a 80-200 f/2.8 or 70-200 f/28 would be than the current versions?

Also whether there's any speculation that Nikon might make DX versions of its faster bigger lenses if the size and weight savings would be substantial?

SF said:

Just curious if someone who knows about such things can predict how
much smaller a DX version of a 80-200 f/2.8 or 70-200 f/28 would be
than the current versions?

Click to expand...

Nothing, the 70-200 have 21 glasselements, a diafragmamodule and a VR module. For 200mm/2.8 (means 71.42mm diafragma) at least 15 glasselements are the same, the other need the same place and have the same weight in in both versions and the 2 modules also.

Not smaller, for any tele lens.

The front diameter ist determined by the f2.8 aperture: 200mm divided by 2.8 = 72mm minimum. And the length is determined by the focal length.

The DX version only helps for wide angle design where the angle of view determines the optical design.

norrona said:

Nothing, the 70-200 have 21 glasselements, a diafragmamodule and a
VR module. For 200mm/2.8 (means 71.42mm diafragma) at least 15
glasselements are the same, the other need the same place and have
the same weight in in both versions and the 2 modules also.

Click to expand...

I see. So the same holds for other lenses (DX versions not smaller)?

volkerm said:

Not smaller, for any tele lens.

The front diameter ist determined by the f2.8 aperture: 200mm
divided by 2.8 = 72mm minimum. And the length is determined by the
focal length.

The DX version only helps for wide angle design where the angle of
view determines the optical design.

Click to expand...

Got it. I apologize for what I now realize was a stupid question.

SF said:

Got it. I apologize for what I now realize was a stupid question.

Click to expand...

it's not a stupid question if you don't know the answer. No need to apologise.

I certainly didn't think it was a stupid question. I've learned a lot in this short thread!

slimandy said:

SF said:

Got it. I apologize for what I now realize was a stupid question.

Click to expand...

it's not a stupid question if you don't know the answer. No need to
apologise.

Click to expand...

--
The Lonely Raven

Jack of all Trades,
Master of None

KC9KCZ

As others have said, an actual 70-200mm f/2.8 DX shouldn't be any smaller. However, a lens that matches the field of view of a 200mm lens as used on full-frame sensors, only needs to be 50-135mm for the cropped sensor.

A 50-135mm f/2.8 could be much smaller/lighter. The new sigma 50-150 f/2.8 is a perfect example.

Or a 50-135mm f/2.0 DX could be a similar size/weight as the 70-200mm f/2.8 FF.

I think over the next ten years we are going to see some amazing new lenses designed around the DX sensor with much larger apertures than has been previously possible. Problems with corner sharpness and vignetting might start to creep back in again. But this will be compensated for digitally in-camera, and by advances in sensor technology.

...and it's better than some of the answers you've been getting!

There is not much doubt that the primary variables in lens size
are FL and maximum aperture. However, the story does not
stop there. One only has to compare, say, a 150mm/2.8 for
a Hasselblad with a 150mm/2.8 for a 35mm camera to see
that the coverage circle DOES matter to size and weight.

It is interesting to compare the specs of the new Sigma
50-150/2.8 with the Nikkor 70-200/2.8 and/or 80-200/2.8.

http://www.sigmaphoto.com/lenses/lenses_all_details.asp?id=3318&navigator=6

The Sigma is designed for DX format (and similar), while the
Nikkors are designed for "FF." When operating against their
intended formats, they have essentially the same FOV range
and speed. But the Sigma is about 2/3 the size and weight
of the Nikkors. The weight DIFFERENCE is enough to account
for another (smaller) lens, a big flash unit, or a backup camera
body. That's important, to some of us! (Just ask a back-
packer how much they spend to save 10 grams with titanium
tent pegs or some such!)

Note: It is true, of course that, the 200's have more "reach"
on DX format than a 150. But it is also true that taking the
wide end down to 50 could be of equal value to someone
whose other lens was something like a 17-55.

If (a BIG if) the performance of the Sigma compared favorably
to a Nikkor 80-200/2.8, then I have NO doubt as to which one
I'd rather lug around all day.

So you are absolutely right to think that DX offers the potential
for size and weight savings compared to "FF." However, that
potential is being realized only gradually.

Happy shooting,

Ed