First GH2 hands-on review

Precisely. But not many are getting this point. I'm not sure if Sony gets it. But even if they do, a good theory does not necessarily translates to a solution to help them, unless they have the same AF technology as Panasonic does now.

Another significant advantage of the AF technology of Panasonic is that because it is based on actual imaging information at the sensor level, it inherently avoids of problem of AF lens variation which requires the AF micro adjustment. People are now proud of having that "advanced feature" in their camera, but with Panasonic's AF technology, it would beome such a unnecessary nuisance.

tgutgu said:

Simply because with the GH2 the AF speed seems now close enough to PDAF systems. The only reason for the translucent mirror technology is to use PDAF in a camera with a EVF to get faster AF. With the GH2 this argument is close to void.

So instead of spending R&D in their SLT stuff, Sony could have been better off to invest in CDAF improvements. The result is that the Sony SLTs could have been smaller without the mirror box and likely face the same focus adjustment problems has conventional DSLRs do.

It is forseeable that SLT is a transition technology which will not last for too long.

PhotOptimist said:

Why is it a waste of technology?
Please explain!

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Thomas

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You are an optimist (like I am).
That's why I did order an A55.
Are you ready to compare DR and Noise of both cameras?
Ok, I'll get A55 in October, when you get GH2?
By the way I own a GH1.

Please read the reviews...

Bilgy_no1 said:

No way that Panasonic will implement controls like the X100. They are too forward thinking for that kind of retro controls (and I think they're right).

Hybrid OVF/EVF, yes a very good idea, but only works with fixed focal lens...

Damien
--
http://www.flickr.com/photos/bilgy_no1

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Actually... They did it before. One of the most innovative (or quirky?) dSLRs I've come across was the Panasonic L1 (which also showed up under a Leica nameplate as the Digilux 3.) This pair used exactly the same control scheme the Fuji has - the first digital cameras I'm aware of to do so.

I'm not sure it really fits with Panasonic's view of m4/3, though - which is one reason I'd rather see them add a third party to do it (but Fuji and Leica were my obvious candidates, and neither is showing any sign of it so far.)

What I think Panasonic really needs is a line of sharp fast compact primes, like Pentax's "DA Limited" series - to capitalize on the compactness of the cameras. The 14 is a step in that direction, but the commitment I'd really like to see is a 60-70ish pancake.

The long rumored fast normal zoom that didn't show up at Photokina would be nice, too.
Walter

PhotOptimist said:

Please read the reviews...

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Not sure which feature you are referring to. Too many points are being discussed at the same time and they are difficult to track.

But if you are referring to AF mechanism, Panasonic's technology is very different from Sony's. In Sony, the translucent mirror reflects a small percentage of the light to an AF sensors above for phase-detect autofocus. In Panasonic, autofocus is actually done using the primary image sensor. You may say, what's the difference, they both use a sensor for AF. But there's a fundamental difference. In Panasonic, the primary image sensor actually constantly captures images at a frame rate of 120 fps, and performs AF based on detecting changes in the image signal in the consecutive frames. In contrast, Sony uses a small sensor dedicated for AF. The AF sensor performs phase detection AF based on the incident light without actually capturing and processing image signals. It is an inherent issue with phase detection AF that it actually needs to be calibrated to the optics.

The key of Panasonic AF is the 120 fps performed by the primary image sensor; because its AF is based on detecting changes of the actual image signals, that's why a higher frame rate translates to a higher AF speed, and also why other image sensors aren't capable of doing fast AF of this kind and had to settle sown on phase detection AF.

Panasonic claims that at 120fps, its AF rivals the phase detection AF in high-end dSLRs. I have no idea how true this is. But if they are right, this really creates a strong implication that Sony's translucent mirror technology could be soon deemed a more complex and unnecessary solution. But there is a big if here, which is whether Panasonic's claim is supported. We'll have to wait to see the test reports. Even if they may have exaggerated a little bit this time, I wouldn't be surprised that the Panasonic technology will eventually get there. It is just such a coherent solution.

I am a noob and I'm confused about the lens. The 14mm-140mm lens is better used for video? Why is that? Does it focus a lot faster? So if I get the kit lens with 14mm-42mm it would focus slower? Can anyone tell me.

memo90061 said:

I am a noob and I'm confused about the lens. The 14mm-140mm lens is better used for video? Why is that? Does it focus a lot faster? So if I get the kit lens with 14mm-42mm it would focus slower? Can anyone tell me.

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Yes, it does. But the main reason the 14-140 had the HD label and is touted as being "for video" is aperture.

For most lenses, aperture is something you snap from state to state, as quickly and accurately as feasible. To AF and compose, you want it wide open, for the brightest viewfinder and the most light to the AF sensor. Then you take the picture (or press the DoF preview) and the lens jumps down to the selected aperture. Any delay here annoys the user. Finish with the shot, and it jumps back open for AF.

This behavior works great for a still camera. For a video camera, though... Suppose you are in shutter priority, or in program/auto with the shutter speed already as slow as is practical for the framerate. Then you pan the camera to a darker area, and it needs to let in more light. What happens?

With a normal lens, the lens jumps from the current aperture to the next larger almost instantly - creating a very noticeable jump in light level. With the 14-140, or any lens with "stepless aperture control", the camera can ask for intermediate levels from the lens, so it can be programmed to feather the change over a few seconds to make it less noticeable/distracting.
Walter

edited for a late spelling error...

nosenseofplace said:

now olympus is not able to product a camera like GH2....no expertise + no R&D

pansonic build their sensor (also Nikon dont produce sensors) + has a expertice in camcorder world...and many money to spend

to be truth i dont think olympus has a long life (4/3 world is already dead...they will no more produce any 4/3 lens...users are sure happy now..)

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Last time I checked, the EP serie is a commercial success.

Ahh ok. Thank you! The GH2 sounds like a great camera. 1500 is too much for me right now though.

PhotOptimist said:

I wish my GH1 could come close to D300.
GH1 is in the second league.
Sorry, but it is the fact.
Don't expect from GH2 too much!

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So how much did you spend on a fast focusing lenes for that $1200+ body only camera? How many front focusing issues or rear focusing issues do you have? How often have you had to mess with the micro-adjust to get lenses to focus properly?

I know that my GH1 does focus as fast as my Canon T2i. Numerous people have posted similar results. And it looks like the GH2 will focus twice as fast. The first review said it focuses faster than a 5DmkII.

Back to accuracy. CDAF is is not a mechanical thing that needs to be adjusted for every new lens. It does not go out of adjustment. If done properly, CDAF should nail its focal points 100% of the time. It is a simpler, better system.

Why Sony would waste money trying to get a less accurate focusing system to work with an EVF is beyond me. We will have to see if the a55 will offer micro adjusting for each lens. If not, you will be stuck with lenses that never focus quite right.

You're right CDAF can be more accurate with less calibration than most PDAF systems. But not all, Fuji's new PDAF system is on the imaging sensor so no calibration errors or extra cost but still the speed benefits of PDAF.

And for some shooters, wildlife and sports mostly, the cost and trouble of a well calibrated PDAF system is worth it. The 5DmkII AF system is nothing to write home about as far as comparisons go. The GH2 won't do what a 1DmkIV will do as far as AF tracking during bursts and that would be test for a dedicated sport shooter. CDAF is definitely not "superior" in this environment.

Fast CDAF also puts more constraints on the optical design of the focusing elements in a lens that PDAF is far more tolerant to (PDAF rarely if ever has to quickly reverse the direction of focus the way CDAF must by design). This plays well into the m43 system where all the lenses are designed with this in mind from the start, but for other systems this may not make sense.

Panasonic's CDAF is getting pretty fast and will probably improve more with time, but the basic PDAF methodology makes it possible to do much better in a number of circumstances - particularly high frame rate bursts of stills (not video) with subject distance changing. CDAF has a ways to go in this case which is very different from just how fast you can acquire when in live view and not mid burst.

I also don't understand what Sony is up to with their SLT system at this point. It doesn't seem worthwhile in a lower end EVF based camera - just get a good CDAF algorithm just as you say. And I also think investing in algorithms and cheap processing (that scales with Moore's law) makes vastly more sense for many cameras than fussy manufacturing of separate PDAF sensors. But Fuji's approach may prove a valid way to produce "free" PDAF.

So anyway, don't overplay your hand there on the "superiority" of CDAF I agree with most of what you are saying, but that statement just isn't supportable, there are still many things PDAF can do that CDAF just can't, and will likely have trouble doing for at least a few years yet.

I think you'd be safe to say "as time progresses we'll see fewer and fewer CDAF cameras" and that "for most cameras CDAF seems the more practical technology going forward".
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Ken W

Rebel XT, XTi, Pany G1, LX3, FZ28, Fuji F30, and a lot of 35mm and 4x5 sitting in the closet...

I think the a55 and the announced Fuji X100 with hybrid views are just transition tech to make the traditionalists happy. Once the GH3 comes along with global shutter, I predict the majority of cameras will adopt the mirrorless concept.

--
http://www.pbase.com/lhlim

Everdog said:

PhotOptimist said:

I wish my GH1 could come close to D300.
GH1 is in the second league.
Sorry, but it is the fact.
Don't expect from GH2 too much!

Click to expand...

So how much did you spend on a fast focusing lenes for that $1200+ body only camera? How many front focusing issues or rear focusing issues do you have? How often have you had to mess with the micro-adjust to get lenses to focus properly?

I know that my GH1 does focus as fast as my Canon T2i. Numerous people have posted similar results. And it looks like the GH2 will focus twice as fast. The first r

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It is well known by many pro Canon shooters that while Canon's AF, in general, locks on faster than Nikon's, Nikon's AF is very accurate (and almost as fast). I don't have a D300 but a D90, whose AF is one notch lower that of the D300, and the D90's AF speed and accuracy blow those of the GH1 out of the water. You do not need a $1200 lens to see this.

PhotOptimist said:

Are you ready to compare DR and Noise of both cameras?

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You are aware that there is life in photography beyond DR and Noise, right?
Anyway you can take this graph:

http://www.dxomark.com/index.php/en/Camera-Sensor/Compare-sensors/ (appareil1) 630%7C0 (appareil2) 652%7C0 (onglet) 0 (brand) Panasonic (brand2) Sony

Even though the α55 sensor is new, it's a got a few more MP than the NEX5 and it has a 1/3 EV loss for the mirror, I'll give you that this sensor on the α55 will perform as good as the NEX5. Now take the GH1 graph and shift it 1EV to the right at High ISO's.
Are we splitting hairs already?

There are so many other things that can make a bigger difference (sensor DOF, lens system, interface) that this discussion seems completely academic...

These are two mighty fine cameras that will correspond to 99% of their user's demands. And I doubt that more than 10% of it's users will use more than 50% of what they can do. Are you one of those 10%? Or are you one of the 1% that will use 90%?
--
Duarte Bruno

saghost said:

Bilgy_no1 said:

No way that Panasonic will implement controls like the X100. They are too forward thinking for that kind of retro controls (and I think they're right).

Hybrid OVF/EVF, yes a very good idea, but only works with fixed focal lens...

Damien
--
http://www.flickr.com/photos/bilgy_no1

Click to expand...

Actually... They did it before. One of the most innovative (or quirky?) dSLRs I've come across was the Panasonic L1 (which also showed up under a Leica nameplate as the Digilux 3.) This pair used exactly the same control scheme the Fuji has - the first digital cameras I'm aware of to do so.

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That was also the same as in the Olympus E-330, but actually a different technology than the X100. Basically, they were DSLR's with mirror designs that used different prism constructions. The E-330 added a separate LiveView sensor that allowed for live view while using PDAF (an idea later implemented by Sony in their Alpha cameras).

The X100 has a plain Rangefinder OVF, with an option to project the EVF into the finder. So there's no through the lens view in the OVF (only in EVF).

Damien

--
http://www.flickr.com/photos/bilgy_no1

PhotOptimist said:

You are an optimist (like I am).
That's why I did order an A55.
Are you ready to compare DR and Noise of both cameras?
Ok, I'll get A55 in October, when you get GH2?
By the way I own a GH1.

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Maybe the intended humour of my remark was lost. I think we, as photography consumers. are living in a great age with lots of new and exciting technology. It all seems to advance so quickly right now. It seems that a lot is possible in all the formats.

But you've got to admit, that anytime a new Sony product comes out, there seem to be people who come into this forum and claim that Olympus/Panasonic/m4/3 is now dead, etc.

Damien

--
http://www.flickr.com/photos/bilgy_no1

for photographer who use almost only primes...its just a piece of plastic the A55

there is ANY fast wide prime !

panasoinc has the 20(40mm) 1.7 and the new 14(28mm F2.5)

with sony you have only zoom...its not a question of quality (primes are better but not always) its that some photographers or photojournalist like me and many ohterthink that zooming its a lost of time and composition is worst....

so the only fast lens you have its the sigma 20mm f1.8 (ooopss.... sigma lens dont work on A55...and also if works its a horrible lens...)

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angel

http://www.photographyblog.com/news/hands-on_with_the_panasonic_gh2

"Our first impression was, “wow, this thing is really fast to focus!” Panasonic claims AF speeds as fast as 0.1 second with the 14-140mm lens set to its widest setting - and indeed, we found that focus acquisition was basically instantaneous at that focal length, even in the relatively dim lighting of the stand. What was possibly even more impressive though was that it focussed almost as quickly with the lens zoomed all the way in to 140mm - it was almost scary to see a completely blurred subject standing at the other end of the room snap into focus in a fraction of a second. Of course further testing needs to be done to see if this blazing speed doesn’t compromise accuracy, but our first impressions were extremely favourable."

Are aware of Zeiss lenses available?

Bilgy_no1 said:

saghost said:

Bilgy_no1 said:

No way that Panasonic will implement controls like the X100. They are too forward thinking for that kind of retro controls (and I think they're right).

Hybrid OVF/EVF, yes a very good idea, but only works with fixed focal lens...

Damien
--
http://www.flickr.com/photos/bilgy_no1

Click to expand...

Actually... They did it before. One of the most innovative (or quirky?) dSLRs I've come across was the Panasonic L1 (which also showed up under a Leica nameplate as the Digilux 3.) This pair used exactly the same control scheme the Fuji has - the first digital cameras I'm aware of to do so.

Click to expand...

That was also the same as in the Olympus E-330, but actually a different technology than the X100. Basically, they were DSLR's with mirror designs that used different prism constructions. The E-330 added a separate LiveView sensor that allowed for live view while using PDAF (an idea later implemented by Sony in their Alpha cameras).

The X100 has a plain Rangefinder OVF, with an option to project the EVF into the finder. So there's no through the lens view in the OVF (only in EVF).

Damien

--
http://www.flickr.com/photos/bilgy_no1

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You're right. But I guess I should have been more clear. Yes, it had a hybrid viewfinder of sorts - but I was actually responding to his other point - that Panasonic was "too forward thinking" to implement Fuji's control scheme - which the L1 and Digilux 3 have.
Walter