# 28-400 2.8



## wdh777 (Jan 1, 2013)

So I don't understand the physics of lenses but if they can why couldn't they make a 28-400 2.8 lens. Even at 15,000 it would be worth it at the same price of All three combined.


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## kirispupis (Jan 1, 2013)

If they made one it would be at least 20k and the optics would suck compared to the equivalent primes. In general the longer the focal range the worse the optics.


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## BrandonKing96 (Jan 1, 2013)

They'd never manage to make the optics justify the price. And if they did, I have a feeling you'd have to be hercules to be able to carry it.


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## sandymandy (Jan 5, 2013)

I want 14-1200mm 8) Probably would weigh 80 kilo or such lol


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## Rat (Jan 6, 2013)

Focal length divided by widest aperture is minimum lens diameter. A 400/2.8 has a diameter of at least 142mm, and your 28-400 would too, of course. The 1200 would have a diameter three times as big, again not counting the thickness of the housing.

I think size and weight (and cost too) put a 28-400/2.8 outside of the realms of practicality. Imagine the 28-300, and then (I'm guessing here) about twice as big in all directions, and if so, at least 4 times the weight (which estimate puts it at 6.5kg). If you're going to put it on a tripod, which you'd need to, it's not at all versatile and even less of a walk-around lens. You'd be a lot better off having a tele on the tripod and a second camera for anything under 100mm on your hip. Would probably be cheaper too - 20k$ seems a conservative estimate if you know that Sigma's 200-500/2.8 already is in the five figure range.


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## Mr Bean (Jan 6, 2013)

kirispupis said:


> If they made one it would be at least 20k and the optics would suck compared to the equivalent primes. In general the longer the focal range the worse the optics.


+1. The bigger the range, the bigger the compromise in aberrations.


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## ahab1372 (Jan 7, 2013)

Check out some of the lenses here: http://www.canon.com/bctv/

Heavy, IIRC $15k is not going to cut it, and I think the image circle is not large enough for a dSLR. In other words, not practical


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## Videoshooter (Jan 7, 2013)

I think everyone is severely underestimating the size, weight and price of such a lens. 

The closest lens to compare to is the Sigma 200-500mm f/2.8 (three feet long, one foot wide, 15kg, $25,000), which has a bit more on the long end but is still only less than 1/5th of the zoom range of a hypothetical 28-400mm. It's also priced in Sigma dollars from the mid-90's so compare that to current Canon prices and the price would be a lot higher for the hypothetical lens (ie hundreds of thousands). 

Plus there's a few other issues too - a lens that big needs a lot of gears and motors to drive the zoom mechanism which makes AF a lot slower. My guess is that, like the Sigma, it would also need it's own independent battery as well. 

And even if you had this lens, how are you going to shoot with it? You'll probably need a geared industrial head mounted on some very sturdy sticks (so add another hundred grand to the equation). 

All things taken into account, it's easy to see why they do not make such a lens. A 30kg + lens that costs more than your house and requires a three-man team to set up and operate? No thanks!


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## Nathaniel Weir (Jan 7, 2013)

What you need http://www.adorama.com/CAE30300EF.html?utm_term=Other&utm_medium=Shopping%20Site&utm_campaign=Other&utm_source=pgrabl


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## AprilForever (Jan 7, 2013)

Those sort of lenses are in broadcasting. I once saw a 18-300 (I think...) f 1.4!!!


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## Hillsilly (Jan 7, 2013)

Thinking outside the square, there are non-Canon options. The Panasonic FZ200 has a 25-600mm f/2.8 lens. Costs $599 and weighs 537 grams. It shoots 12 frames per second. Apparently IQ is ok in good light.


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## TexPhoto (Jan 7, 2013)

The Panasonic FZ200 4.5-108 mm, and a sensor the size of a fingernail. (Equivalent to a 25-600mm on FF) It is much easier and cheaper to make this stuff much smaller, but the quality of the photo is not close.

wdh777, Let me ask this. Canon makes a 28-300mm f/3.5-5.6 L IS. Do you own one? Why not? It's not a 2.8, but it does not cost 15K either.


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## Halfrack (Jan 7, 2013)

wdh777 said:


> So I don't understand the physics of lenses but if they can why couldn't they make a 28-400 2.8 lens. Even at 15,000 it would be worth it at the same price of All three combined.



At $150k is more likely... Understanding how trade offs are made would help. The 30-300mm lens is a good example - remember, to go wide means you need to squish all your glass into a really short length, and all those pieces of glass moving really far apart in sync to give optical perfection at every point along the way.


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## Videoshooter (Jan 7, 2013)

AprilForever said:


> Those sort of lenses are in broadcasting. I once saw a 18-300 (I think...) f 1.4!!!



These lenses are designed for 2/3 inch cameras outputting 1080p, not FF DSLR's resolving upwards of 20mp. It's much easier to design a lens for a smaller sensor.


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