Why is there no 24-70mm f/1.4?

How sweet would that be?  I'm fearful of what the price tag might be.  Is there any good reason aside from price why this lens doesn't exist?  

That would be nice, but with the ISO range in most pro DSLR's, you wouldn't need it? 

Because you wouldn't have any portability at all. Cost prohibitive as well.

McBeth Photography wrote: Because you wouldn't have any portability at all. Cost prohibitive as well.

Correct. I'd cost 10,000 USD, and weigh 15 pounds.

Eliffman wrote: That would be nice, but with the ISO range in most pro DSLR's, you wouldn't need it? 

Do you own or have you shot with a 1.4 lens before?  It's not really about getting more light inasmuch as it is about having DOF control.  If you shoot at f/4 all the time then yes there's little difference between a 1.4 lens and a f/4 lens.

They could certainly manufacture one, but to have a constant aperture of f/1.4 it would be the size and weight of a rocket launcher.   (My 24-70 is heavy enough to carry around all day.)

Scotty wrote:

McBeth Photography wrote: Because you wouldn't have any portability at all. Cost prohibitive as well.

Correct. I'd cost 10,000 USD, and weigh 15 pounds.

Sigma is rumoured to be producing a 24-70 f/2 in the near future. Not quite f/1.4, but a stop faster than f/2.8 and much shallower DOF.

Scotty wrote:

McBeth Photography wrote: Because you wouldn't have any portability at all. Cost prohibitive as well.

Correct. I'd cost 10,000 USD, and weigh 15 pounds.

I would not mind the weight so much, but the price, would be a weight I would not want from my wallet. I would rather see them make a 400-800 f/4 VR over a 24-70 f/1.4.

Joves wrote:

Scotty wrote:

McBeth Photography wrote: Because you wouldn't have any portability at all. Cost prohibitive as well.

Correct. I'd cost 10,000 USD, and weigh 15 pounds.

I would not mind the weight so much, but the price, would be a weight I would not want from my wallet. I would rather see them make a 400-800 f/4 VR over a 24-70 f/1.4.

That'd be probably be in the $30,000 USD range.

Scotty wrote:

Joves wrote:

Scotty wrote:

McBeth Photography wrote: Because you wouldn't have any portability at all. Cost prohibitive as well.

Correct. I'd cost 10,000 USD, and weigh 15 pounds.

I would not mind the weight so much, but the price, would be a weight I would not want from my wallet. I would rather see them make a 400-800 f/4 VR over a 24-70 f/1.4.

That'd be probably be in the $30,000 USD range.

Yeah but it would be a great lens. The 24-70 is supposed to be a general walk around lens, but most long glass is not. Also I expect pornographically high prices on constant aperture long lenses.

A 400-800 f/4 would have a 200mm wide front element and be about the same size as Sigma's 500 f/2.8. Definitely not hand holdable!

gfinlayson wrote: A 400-800 f/4 would have a 200mm wide front element and be about the same size as Sigma's 500 f/2.8. Definitely not hand holdable!

and a suitable UV filter would probably be as expensive as a good macro lens

gfinlayson wrote: Sigma is rumoured to be producing a 24-70 f/2 in the near future. Not quite f/1.4, but a stop faster than f/2.8 and much shallower DOF.

This might be worth keeping an eye on.  Sigma has been coming out with some nice glass.  Thanks for sharing this.

gfinlayson wrote: Sigma is rumoured to be producing a 24-70 f/2 in the near future. Not quite f/1.4, but a stop faster than f/2.8 and much shallower DOF.

Define "much"?

Using the calculator at dofmaster.com, for a D800 (full frame) with 85mm at 10 ft (think portraiture), the DoF at f/2.8 is around 8"; at f/2 it's 6". Not a huge difference there, in my book.

It might be more relevant to point out that bokeh will be enhanced by the larger aperture. Even though it's related to DoF I think that's where the emphasis lies.