Wide aperture zooms - theoretically possible?

cuthbert

cuthbert

Pugh Pugh Barney McGrew Me Dibble and Grubb
Messages
2,042
Name
Mark
Edit My Images
Yes
the widest aperture zoom lens sold by our favourite manufacturers is an f2.8 and i'm surprised in a way that we haven't seen anything faster than this.

i could see that a 70-200 f1.4 zoom would be (judging by 200 f2 primes) absolutely enormous, heavy and very expensive.

but shorter telephone lengths surely wouldn't be so impracticable?

my sigma 85 1.4 not any bigger than my 24-70 2.8, so in theory, a 24-70 1.4 wouldn't be all that huge... but would it be possible?

perhaps this is the stuff of dreams, but a 24-85 1.4 would be just an amazing lens, probably the only one a lot of portrait/wedding photographers would ever need.

so why hasn't one been made?

if it's cost, surely premium lenses like the 50L, 85L and 200f2L suggest that there is certainly a market for them at the higher end, or is that they just can't be made and f2.8 is going be as good as it's going to be?
 
I think they would be seriously heavy and seriously expensive and you would need to keep yourself in peak fitness just to be able to use the thing.

Zooms are all about convenience really, but big/heavy/expensive will not tempt people away from their quality primes.
 
With a prime lens it's a lot easier to design a set of optics that perform at their best for the chosen focal length of the lens you are building.

As we all know, zoom lenses have to compromise slightly, because they have to work over a variety of focal lengths. I am just wondering if the introduction of a super wide aperture would be one compromise too far, which would render a super wide zoom lens as useless.

Just conjecture on my part.
 
Compare a 17-50mm f/2.8 to a 50mm f/1.8. The 50mm is pretty small, but the 17-50mm is pretty big in comparison. You probably need it as big as Sigmas 200-500mm f/2.8! :lol:
 
Size and price is your answer.

The size would be large and coupled with a huge price tag it would mean financially it would be impractical.

Look at the Canon 100-400 f4.5 to f5.6 vs the Nikon 200-400 f4.

Twice the weight, best part of four times the price and probably the former sells significant quantities vs the latter being a rare exotic beast.

Alternatively, look at the 70-200 f2.8 vs a 200 f2 - and thats comparing a zoom to a prime, the prime being much cheaper and lighter....

Who would buy an expensive, heavy item... so why spend millions designing and tooling for it...
 
desantnik said:
Alternatively, look at the 70-200 f2.8 vs a 200 f2 - and thats comparing a zoom to a prime, the prime being much cheaper and lighter....
Click to expand...

Sorry the prime weighs a tone and costs like a new budget car. 70-200 2.8 non-IS is well under 1k and just over 1kg.
 
I think another thing to consider is that some people simply prefer working with primes. I already have to consider aperture, shutter speed and white balance so I'm actually grateful that I don't also have to consider the ideal focal length setting each time I want to take a shot.
 
If it was possible, then it would have been done.

daugirdas said:
Sorry the prime weighs a tone and costs like a new budget car. 70-200 2.8 non-IS is well under 1k and just over 1kg.
Click to expand...

I think that's a typo for f/2.8.
 
daugirdas said:
Sorry the prime weighs a tone and costs like a new budget car. 70-200 2.8 non-IS is well under 1k and just over 1kg.
Click to expand...

No, sorry, what I meant was that to make a 70-200 f2 would be far heavier than the 200 f2, the latter of which isn't exactly light and fluffy to start with :D
 
I read a rumour a while back that Canon is working on a 17-55 f2 lens in EFS fitment. Olympus users already have the option of a 14-35 f2 zoom and a 35-100 f2 zoom. 14-35 and 35-100
 
Last edited:
CSB said:
I read a rumour a while back that Canon is working on a 17-55 f2 lens in EFS fitment. Olympus users already have the option of a 14-35 f2 zoom and a 35-100 f2 zoom. 14-35 and 35-100
Click to expand...

If the canon rumour is right, then by working the zoom only in EFS fitting they'll of helped themselves no end by avoiding the issues with edge softness and reverse telephoto designs so avoiding some of the compromises that I would of though make very fast zooms difficult.

Even more so with the olympus considering the 4/3rds sensor size
 
boyfalldown said:
If the canon rumour is right, then by working the zoom only in EFS fitting they'll of helped themselves no end by avoiding the issues with edge softness and reverse telephoto designs so avoiding some of the compromises that I would of though make very fast zooms difficult.

Even more so with the olympus considering the 4/3rds sensor size
Click to expand...
That would actually reduce the gap between crop and 35mm sensors and give them more right for existence, besides being cheaper.
 
boyfalldown said:
I'm confused by that - sorry can you explain
Click to expand...
Well, crop sensors perform worse in terms of colour reproduction and ISO capabilities. With an f2 zoom, they win some grounds back to 35mm sensors and f2 zooms would finally take proper advantage of the smaller projection circle required, besides saving costs on lenses.
 
CSB said:
I read a rumour a while back that Canon is working on a 17-55 f2 lens in EFS fitment. Olympus users already have the option of a 14-35 f2 zoom and a 35-100 f2 zoom. 14-35 and 35-100
Click to expand...

I doubt that Canon would attempt a 17-55 f/2. The f/2.8 is already a substantial lens and well at the top end of most people's budget. I suspect that, at any size and cost, nobody would put up with its performance compromises.

Those Olympus lenses are interesting, but they're 'cheating' in that they only cover the 4/3rds format, which is one quarter the size of full frame. They're a good illustration of the compromises involved, and how they can be mixed and matched.

Olympus make some very nice lenses indeed, but take the 14-35 f/2 (28-70 equivalent focal length to FF, and delivering depth of field equivalent to f/4). F/2 is great, but it's a modest range, and that lens costs almost two grand!

The closest Canon can get to that, and make it work on FF, is the 16-35L f/2.8 - also expensive at over £1k.

Then there is another way of looking at it, and a very nice way IMHO, is the Canon EF-S 17-55 f/2.8 (27-88 equivalent focal length to FF). It covers the Canon crop format sensor, which is a lot bigger than 4/3rds but still less than half the area of full frame - it has good range, f/2.8 which is pretty good, IS, and is very sharp indeed, cost £750.

Cistron said:
Well, crop sensors perform worse in terms of colour reproduction and ISO capabilities. With an f2 zoom, they win some grounds back to 35mm sensors and f2 zooms would finally take proper advantage of the smaller projection circle required, besides saving costs on lenses.
Click to expand...

So far, the signs aren't promising!

Personally, I don't think 4/3rds will make it as a format for serious enthusiasts, though it will surely be a big hit, and growing, a little down the scale. It's main appeal, is smaller cameras and especially smaller lenses.

If you look at what you get with Olympus for example, in terms of image quality per pound spent on their top end cameras and lenses, you get a much better return by starting out with a bigger sensor in the first place.
 
Here's another way of looking at it.

Have Nikon ever made an f/2 zoom? No.

But over the years they have made some incredible, impractical, expensive lenses:
I think it's fair to conclude that if it were possible to make a decent f/2 zoom, regardless of expense or practicality, Nikon would have done so.
 
The main reason, I believe, for not making ultra bright zooms is simply because they would be utterly awefull optically. The tollerances required to make a zoom lens sharp at all focal lengths and wide open are slim to say the least. Making a lens that can do even 3x optical zoom, at 2 stops brighter, say, at F/1.4 would perform terribly; softness being the main drawback.

Of course, it's all possible, but as said the size, weight and cost would be silly, coupled with sub standard optical and focusing performance... people simply wouldn't buy it.
 
A lot of those long exotic things Stewart mentioned had specific military applications - you seen some of them mentioned in the very excellent book about Brixmis and their (illegal) surveillance operations in the Deutsche Demokratische Republik...

Just like NASA, in those cases a stupidly high cost and small production run wasn't really a problem - the value of what they delivered was many times that of what it cost to collect it.
 
You must log in or register to reply here.
Back
Top