GH2 Will the New X-Series Powered Zoom Lenses be Parfocal?

Ben Totman said:
until an announcement no one will know, we dont even know the aperture specs of the lenses yet.
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You realize that he is talking about the 2 lenses that have already been announced, and not the 12-35 and 35-100 prototypes. So we already have the specs.

Seems to me that because they are such short lenses, it wouldn't be hard for them to maintain focus while zooming.

Heres Hoping.
 
If we are doing any wild assed guessing here, I am guessing that yes, they will be. The announcement is saying the 14-42 is slated to be the kit lens on the GF3. That camera is aimed at the general public. Not putting it on just opens the door to a ton of newbs pestering tech support for why it's not acting like their camcorder. Also if it isn't, a power zoom is a real useless and expensive function where parfocal would be a great incentive to upgrade for the extra cash.
 
" if it isn't, a power zoom is a real useless and expensive function"
Totally agree. What would be the point? I have long been posting into a seeming black hole regarding the need for a decent powered zoom option for DSLRs. Glad to hear any movement at all on what was heretofore considered sacrilege. Let's hope it's all good.
 
Meh. Who cares. They're all pig slow anyhow. Might use one to hammer nails, but not put on any camera. Panasonic should buy a clue and release fast lenses for affordable prices.
 
No need for a Parfocal optical design because zoom and focus are both electronic. The CPU can calculate how to adjust focus based on focal length.

Chris
 
OldCorpse said:
Meh. Who cares. They're all pig slow anyhow. Might use one to hammer nails, but not put on any camera. Panasonic should buy a clue and release fast lenses for affordable prices.
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But you have to understand that these products are filling a need. Someone who is looking at a GF2 or GF3 and thinking, that's nice and small but the lenses are HUGE in comparison. This is to fill that spot. Because if they made them faster they'd run into 2 problems: first and most important, they'd have to be bigger to accommodate larger apertures, and secondly they'd be more expensive to achieve this. Both of these points go directly against what these lenses have been designed to accomplish.

What I could see happening sometime in the future though would be a faster more expensive version offered as a step up alternative to those who wanted it for purposes such as video.

But stills will always be their primary concern with any m43 product, and for stills shooters looking for something small for a kit lens, these fit the bill.
 
" They're all pig slow"

Slower than most dedicated video cams in similar price range with motorized zoom? My interest is the creative visual possibilities of DSLR without giving up the ability to accomplish a smooth online zoom. I still expect to light the situation most of the time..since available is often none too flattering.
 
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Correct me if I'm wrong about this, but I seem to remember that before AF, many stills camera zooms did used to maintain focus as they were zoomed. From memory I seem to remember in the photo press there used to be a lot of argument that such and such a lens wasn't really a zoom lens, but a varifocal lens because it didn't maintain focus when zoomed. Without looking this up, I also seem to remember that after AF became a feature on all stills 35mm SLRs, that the manufacturers dropped the constant focus feature because an AF camera automatically refocuses itself for stills. So it might not be so difficult to achieve this on a moderate sized lens for a stills camera. It's only recently that video got implemented in stills cameras, so there wasn't any need for maintaining focus on AF stills SLRs before the introduction of video, where the PDAF no longer works. Even live view is a relatively new feature on DSLRs.

I've only got one old manual focus zoom lens left, and unfortunately it's a push pull design. Whilst it does seem to maintain focus when zoomed, it's a bit difficult to be certain because of its push pull design, which means you zoom with the focus ring.

In fact I seem to remember that some of the famous old Vivitar Series 1 stills lenses were sold as varifocals and not zooms because of this. I just looked it up and found a link below. It seems after AF became almost universal for stills cameras, that the manufacturers dropped the distinction between zooms and varifocals because it no longer seemed relevant.
http://www.suite101.com/content/vivitar-cult-classic-camera-lenses-a34579
 
from dpreview "During video recording, you can still zoom the lens but it's limited to its slowest speed. This both helps minimise operational noise (the motor is barely audible on your soundtrack), and makes movies more pleasant to watch, as rapid zooming rarely works well."

Ah..certainly wouldn't leave that up to the user now, would they? Not that you would EVER want to quickly zoom in on something while shooting video. Think you can quickly adjust it manually or will you have to switch to manual for quicker zoom adjust?
 
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That's kind of a bummer. I love it when a proper video camera has a motorized zoom that starts off so slowly that you can barely tell its zooming, and then you an incrementally, ever-so-slightly increase the speed of the zoom. Yeah, that's a lot to ask for from a pancake zoom, but it would have been neat.
 
Sam,
Might be able to do what you want at the slow end. I just find it lame to exclude fast zoom. dpreveiw's rationalization is pretty lame.
 
stoneinapond said:
Panasonic is right. Fast zooms look wierd. If you really need that, do it in post.
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Have you ever seen interviews dealing with a big figure and they get into some serious topic? The interviewer will ask a tough question and immediately there will be a kind of abrupt fast zoom into the subject's face. Very powerful and effective shot. Fast zooms do not looks weird for interviews or for "The Office" style zooms. For traditional narratives however, it can look weird.
 
Even if it's edited out later, it is very helpful to be able to quickly zoom to change the shot. This whole DSLR "cinema" (zoom=bad) religion is getting ridiculous.
 
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