Fast zooms: constant or not?

Discussion in 'Open Discussion' started by alphasierra, Sep 28, 2011.

  1. alphasierra

    alphasierra Mu-43 Rookie

    16
    Jun 13, 2011
    Melbourne, Australia
    A lot of people seem to be waiting for a fast zoom with bated breath - and I'll probably get one myself if it's not too expensive. One thing that often comes up in that type of discussion is peoples enthusiasm for constant apertures - e.g. hope that the coming 35-100 might be constant f2, or constant f2.8. Often, it seems like this is a really major selling point, rather than just something that's a nice bonus.

    I understand the basic idea that a constant aperture means zoom has no effect. But, a question: would people rather have a constant aperture, or one which is faster on the short end? Let's say (for argument only) they can't make a constant 35-100/f2 lens that's an acceptable size/price, but can make a 35-100/f2-2.8 (f2 at 35mm to f2.8 at 100mm). Is it preferable that the short end be restricted to give a constant f2.8 lens, or would people rather have the extra speed available at the short end (to use if desired, or set it to 2.8 if you want constant aperture)?

    It seems like it would be easy to make 'constant' zooms by using software to cripple the 'faster' end of a 'variable' lens in software. But this doesn't seem like such a good idea to me...
     
  2. RT_Panther

    RT_Panther Mu-43 Legend

    May 4, 2011
    Texas
    This is the million dollar question....(What's "too expensive"..)
     
  3. flash

    flash Mu-43 Hall of Famer

    Apr 29, 2010
    1 hour from Sydney Australia.
    Gordon
    Fast zooms are expensive, even the cheap ones like Sigma and Tamron or Tokina. They're just too complex to make on the cheap.

    If a fast lens comes out that is a variable aperture, I won't buy it. I'd rather have a constant 2.8 than a 2-2.8. It makes shooting in manual a PITA. I will be sorely disappointed if it's a variable aperture lens. Panasonic already has one good constant aperture zoom (7-14) so I suspect the new ones will also be constant, although if I had a choice I'd rather that it's made by Olympus.

    Gordon
     
  4. hkpzee

    hkpzee Mu-43 All-Pro

    Sep 5, 2011
    Hong Kong
    Patrick
    If they can make the lens not larger than the 14-140, but with a variable aperture of 2-2.8, I would seriously consider getting one (of course depend on price also).

    Physically, I just don't think they can make a constant f/2 zoom this small... but then again, what do I know about camera physics...
     
  5. Biro

    Biro Mu-43 All-Pro

    May 8, 2011
    Jersey Shore
    Steve
    It's interesting... In the regular four-thirds system, Oly has some very nice zooms. But almost all are variable aperture - even the faster ones. Two High Grade 4/3 zooms come to mind: the 14-54 f/2.8-3.5 and the 50-200 f/2.8-3.5. I personally could live with that kind of aperture range if the optics were very good and it kept both price and size down.

    Of course, there's Oly's Super High Grade 4/3 zooms, which are constant aperture, which is generally f/2.0. But those lenses are larger... with price tags in the thousands of dollars each.
     
  6. hkpzee

    hkpzee Mu-43 All-Pro

    Sep 5, 2011
    Hong Kong
    Patrick
    I happen to own both the 14-54 II and the 50-200 SWD for use on my E-P3, and I love the quality of those lenses, so if they came up with the same specs for the m4/3 zoom lenses, but at half the size of the 4/3 zooms, and focus faster than the 50-200 on m4/3, I will be all over them...
     
  7. Ned

    Ned Mu-43 Legend

    Jul 18, 2010
    Alberta, Canada
    Of course I'd prefer a constant aperture at the same speed (in your example, both have an f/2 maximum). But the real concerns with that are size and price. Not as much in manufacturing cost as in size... The increase in size just to make that constant aperture is huge, and not necessarily worth the small increase in speed at the tele end.

    This is all assuming the same high quality of optics, of course. Yes, Sigma, Tokina, etc. have constant aperture lenses which are no larger and even cheaper than the Olympus versions with variable apertures... but the Zuiko lenses are much sharper and higher quality.

    With the increasingly small sizes of our bodies, the oversized lens becomes more and more unwieldly. I think that's the biggest issue these days.
     
  8. nickthetasmaniac

    nickthetasmaniac Mu-43 All-Pro

    Jan 11, 2011
    I couldn't give a flying doodle if a zoom is a fixed aperture or variable aperture, as I never shoot in conditions where that kind of precision matters or is even noticeable, and yes, I would prefer a variable 35-100/f2-2.8 over a fixed 35-100/f2.8...

    But, that's in Hypothetical-Land. The fact is that in basically ever case I can think of, it goes the other way... So rather than the short end becoming faster with a variable zoom, the long end becomes slower...

    ZD 12-60/f2.8-4
    PL 14-50/f2.8-3.5
    ZD 14-54/f2.8-3.5
    etc etc...

    Coming from primes, I'm become accustom to speed, and I'm simply not interested in a lens slower than f2.8 at any focal length...
     
  9. Ned

    Ned Mu-43 Legend

    Jul 18, 2010
    Alberta, Canada
    To me, I do notice the difference as the long telephoto end is normally where I need the speed the most! I really don't need it on the wide end.

    However, I also see enough advantages to variable aperture lenses that I'm happy with both. :) Everything's a compromise.
     
  10. pharaviel

    pharaviel Mu-43 Veteran

    313
    Jun 20, 2011
    Reggio Emilia, Italy
    Daniele Frizzi

    I know it's impossible by design but I would love a 12-60 f 4-2,8.
    Yeah, slow on the wide end (more dof for landscapes) and fast on the long end (less dof for portraits).
    I know how aperture and focal lenght works so I know this lens isn't coming, but this would be my perfect variable aperture lens.

    Sent from my iPhone using Mu-43 App
     
  11. alphasierra

    alphasierra Mu-43 Rookie

    16
    Jun 13, 2011
    Melbourne, Australia
    I'll apply the famous phrase the US Supreme Court used to define pornography: I know it when I see it.
     
  12. alphasierra

    alphasierra Mu-43 Rookie

    16
    Jun 13, 2011
    Melbourne, Australia
    One of the thoughts I had in my head (but perhaps didn't effectively explain) is what you've said - the perception of the long end getting slower. It wouldn't be hard to make a constant PL 14-50/f3.5 by crippling the short end. Although this would make it a constant zoom, I can't see many people buying it in preference to the PL 14-50/f2.8-3.5 with the faster short end. What I was thinking is that it's a glass half full/empty situation: If we got a f2-2.8 zoom, do we complain that the long end gets slower, be grateful that we get f2 at the short end, or wish the whole thing was restricted to f2.8?
     
  13. nickthetasmaniac

    nickthetasmaniac Mu-43 All-Pro

    Jan 11, 2011
    Like I said, for me I'd be quite happy with a variable that was f2.8 at its slowest :smile:

    Thinking about it though, there's quite a few relatively slow constant f4 zooms (Canon 24-105L, Pentax DA 16-45, Nikkor 24-140 etc...) that are very popular...
     
  14. addieleman

    addieleman Mu-43 All-Pro

    Aug 5, 2010
    The Netherlands
    Ad
    I used to care about apertures that stayed the same during zooming when I used a Nikon F3 and a hand-held lightmeter, so I used constant-speed zoomlenses then. Now I don't care anymore because I always shoot in some automation mode and if I don't, aperture values you set on the camera are the real aperture value, irrespective of the zoom position.

    Watch the videos in this thread and you start wondering why you care at all about camera features :smile:.
     
  15. goldenlight

    goldenlight Mu-43 All-Pro

    Jan 30, 2010
    Essex
    John
    Why should variable aperture make a difference when shoooting manual. In manual if you set f2.8 then f2.8 is what you get. OK, setting f2 at the wide end and then zooming would cause a problem, but no advanced user is going to fall for that one, are they? :smile:
     
  16. flash

    flash Mu-43 Hall of Famer

    Apr 29, 2010
    1 hour from Sydney Australia.
    Gordon
    Yes It would and yes I would. :biggrin: I also have the 14-54II and it's a great lens although with more DOF than a FF sensor, so I tend to use it wide open. It's only half a stop so the inconvenience is minor, but it's still an inconvenience when I'm working and things are changing fast. An annoyance i just dont need. I've been using constant aperture zooms for a decade. It's a backward step I don't appreciate. I'm the guy who gladly pays 2K for a 50mm 1.2 instead of $400 for a 50mm 1.4. Or 7k for a Leica instead of 2k for a 5D2. Some are happy to compromise for a lower price. I'd rather pay more and not compromise. At 100mm at f2 and a shutter speed of 1/200 is only 1/100 at 2.8. That's a big deal if you have to work fast. With a constant zoom you'll always have the higher speed, and can set the best ISO accordingly. A variable aperture zoom will mean I need to set a higher ISO than I should have to to get good shutter speeds at the long end.

    Gordon
     
  17. goldenlight

    goldenlight Mu-43 All-Pro

    Jan 30, 2010
    Essex
    John
    If only I had the money I'd be with you all the way! To me, the 14-35mm f2 is a dream lens.....on the E-5 that is, it would be far too big on Micro Four Thirds. I would happily settle for the same lens at f2.8 if they could make it small enough. :smile:
     
  18. flash

    flash Mu-43 Hall of Famer

    Apr 29, 2010
    1 hour from Sydney Australia.
    Gordon
    and they're very sought after. And they've tested better than the variable aperture lenses that Olympus makes.

    If m4/3 ever wants to appeal to more than the enthusiast market then they will have to have constant aperture lenses available.

    Gordon
     
  19. fredlong

    fredlong Just this guy...

    Apr 18, 2011
    Massachusetts USA
    Fred
    I'd be happy with a variable aperture. In part for the smaller size. I did'n switch to m4/3 for the compactness of some of the cameras. The G2 seems "normal" sized to me coming from OM film cameras. But constant aperture fast zooms are really big. Big enough that I might hesitate to carry one casually.

    The biggest reason though is price. I could likely afford a variable aperture lens, but a constant aperture is unlikely to fit in my budget for the foreseeable future.
     
  20. ~tc~

    ~tc~ Mu-43 Hall of Famer

    Oct 22, 2010
    Houston, TX
    but unfortunately, you have it backwards - the short end is always crippled on a constant zoom lens. Look at the Panny 7-14 f/4. For the same size aperture opening, (ie the physical constraint/operation of the moving parts) it would be f/2 at the 7 mm end. They have choked it to meet the long end, so that they can market it as a constant aperture. I would rather have f/2-4.

    X2 for the poster above that said this mattered in the days before built in light meters. You wanted, NEEDED to take ONE reading with your handheld (or guess) and then set it and not have it change. Wit today's automated cameras, a variable zoom gives you the best chance of decreased DOF and faster shutter speeds