Is anybody except me waiting for a standard zoom lens with constant aperture?

spraynpray

"Olympus has always had good cameras and great glass. Many seem to forget brands like Olympus, "

Absolutely +1

"Just over $9,000 for the whole lot. Similar Nikon lenses you would be close to double that."

When you look at the cost of Scott Bournes 1DX bodies and full range of 'L' lenses, like I said, the Oly is a tiny fraction of the cost.

I find it strange that the Oly sensor is so highly praised when it is M4/3rds and yet there is a thread on here where the difference between DX and FX is judges to be significant enough when I had said that soon there will be mainly the DoF as the difference.

TaoTeJared

M4/3rds sensors have something different to them and the way the images produces feel. I don't know how to describe it but it is just different and it's not just the DoF. I'm not a big fan of it, but it is growing on me. Seeing Fuji's announcement for the X100s that has a new AF design that is suppose to be the fastest in it's class and the Xtrans sensor, It looks like that may be my next upgrade. I love the way fuji files look.

sevencrossing

The threads sure do meander since the new forum came along - what happened to the "Hey - stick to the topic" police?

Back on topic.

Hint Hint


standard zoom lens with constant aperture?

Ironheart

Heh, I pointed out that if you leave it on f/4 it is constant. Consider the 2.8 at the wide end a bonus. There was a whole thread on why constant aperture lenses couldn't be variable at the wide end, since it was "in there" anyway. The trade off is image quality, so keeping it stopped down to f/4 gives good quality, low weight, and a standard zoom range. That's the theory anyway since nobody has apparently seen the Sigma AF 17-70mm f/2.8-4 DC HSM OS macro in the wild yet. BTW, you can get the non-OS version and shave 50grams off the weight, gets you to like 475grams. Not too shabby.


Remember this discussion? http://nikonrumors.com/forum/topic.php?id=27874

This sigma is the proof that you can build an f/4 lens but allow it to be opened up at the wide end, with the resulting loss in quality. Its there if you want it, otherwise keep it on f/4.

soap

By that logic the 18-55 is a constant aperture lens if you set it to f/5.6

Let's change that to another example.

The error in thinking that the 70-200 f/2.8 with it's (obviously) 71mm physical aperture can't instead be a 70-200 f/1->f/2.8 is in believing that there are large enough elements to do 70 f/1. The same is true of most all the other constant aperture lenses. They may have the physical aperture diameter for being a faster lens on the wide end, but they don't have the glass where it's needed. It's not just about the front element, it's about the entire path.

There are plenty of people who would give their left leg for a 70 f/1 - even if it came vignetted and aberated out the ying-yang. It isn't being withheld due to marketing. It's being withheld due to physics.

PB_PM

Hey PB, I caught it on the TWIP podcast number 288 - take a listen - he doesn't say anything bad - says sharpest lenses, great tonality through ISO1600, etc.etc.

I read some of his written reports, on his blog, which hit on all the points I made.

tc88

No one is saying that 70-200 f/2.8 will be 70 f/1 if aperture is fully opened. The final aperture returned to the camera is supposed to also be calibrated using the amount of the light that goes through. Otherwise, your 24-85 f/3.5-4.5 will become 24-85 f/1.5-4.5. However for example, I would guess that 70-200 f/2.8 may perform reasonably at 70 f/2.4.

It will be sharper at f/2.8 compared to f/2.4, but same can be said that it's sharper at f/4 compared to f/2.8.

There can be possible vignetting at 70 f/2.4, but many lens have similar problem.

It will take in more light, so it will be faster.

Another way to look at it, the opening at 70 is clearly smaller than the opening at 200. Since physically it can be opened bigger, and let's say it's opened slightly more to 70 f/2.7. Does anyone expect that the performance falls off the cliff that it's not usable? I would think not. So here you have it, all zoom lens are really variable aperture lens.

There can be many arguments to support a fixed aperture lens, mostly for user convenience and to prevent user screw up. Those are valid reasons, but not exactly related to the physical limitations.

PB_PM

Keep in mind that Nikon (and most SLR lens manufactures) use F stop values in lenses, not the absolute value of the light transmitted (Tstops) through the glass. The chances of a F2.8 zoom lens being F2.8 throughout the entire range is impossible, due to the physical characteristics there of. There are simply too many variables to create a true constant aperture zoom. The aperture given is an average of what can be expected throughout the range (focused at infinity).

Ironheart

Looks like the Sigma 17-70 was made available for preorder today :-) I guess I'll have to put my $ where my mouth is. See the main blog:

http://nikonrumors.com/2013/01/08/sigma-17-70mm-f2-8-4-dc-macro-os-hsm-and-120-300mm-f2-8-dg-os-hsm-lenses-available-for-pre-oder.aspx/

I think this lens will pair well with the 70-300.

JJ_SO

Performancewise I've no doubts, considering the quality they prove with the 35/1.4. But are you sure you'll like the turning focusring in front of the lens? That kept annoying me and was the main reason to sell the 17-50/2.8 which was is a nice sharp lens.

heartyfisher

Looks like the Sigma 17-70 was made available for preorder today :-) I guess I'll have to put my $ where my mouth is. See the main blog:

http://nikonrumors.com/2013/01/08/sigma-17-70mm-f2-8-4-dc-macro-os-hsm-and-120-300mm-f2-8-dg-os-hsm-lenses-available-for-pre-oder.aspx/

I think this lens will pair well with the 70-300.

I am quite sure that there are now at least 3 versions of the Sigma 17-70.
1) no OS version
2) OS version - been out a few years now.
3) NEW, OS version that you can get on preorder now.

So note the specifications when you purchase..

Ironheart

So what's the difference between 2 and 3? Is it the addition of the USB dock for fine tuning the lens? Just to confuse things there is also a 17-70 f/2.8-4.5?

JJ_SO

3 is checked in QC in a different way than 2 and 1. Also, the aperture is 1/2 stop wider, lens caps will be better and the price is, contrary to Nikon's developments, not steeper. It has Macro capabilities and the lens hood will also be safer in position and made from better material.

Ironheart

Did a bit more digging. B&H is a sponsor right?

http://www.bhphotovideo.com/bnh/controller/home?O=&A=compareChart&Q=&ci=274&items=;670041-REG;909805-REG

Looks like 13/17 vs 14/16 lens groups/elements (The newer one has less elements)

And 535g vs 465g. The newer one also has a slightly wider AoV. So a standard f/4 zoom that weighs less than 500g I bet it will work okay on FX too at all but the widest end.

JJ_SO

Didn't want to spoil your fun with researching >:D<
I would not use it for FX, not to use, I don't think it would work: 16-85 Nikkor is vignetting at all focus lengths.

heartyfisher

The easy way to tell the diff between (2) and (3) is the dimensions of the lens barrel. The new one is thinner and shorter and lighter at 79mmx82mm and 465g. The older OS version is 79mm x 88.9mm and 535g.

Note both OS versions(2) and (3) have 2.8-F4.0. The 2.8-4.5 is the Non OS version (1).

JJ_SO

And both have Macro, too. 8->

But the new one looks more stylish! B-)

Ironheart

That's the one I want! :-)