GH4 The GH4 is here!

Does anyone know if this will have a waveform, or will it have a historgram? The AF100's waveform was invaluable, hope this made it into the GH4.
 
I believe the GH4 has a live histogram, adjustable zebras, focus peaking, SMPTE color bars, and a standard audio test tone (all of which are welcome!), but not scopes (no waveform or vector scopes).

Some add-on, 3rd party EVFs and monitors include scopes that could be used with the GH4.
 
Uwe Lansing said:
Some 4K test shots: http://www.youtube.com/watch?v=48PvXDBgB_Y
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That video, while nice and sharp, went in and out of focus several times. Is that most likely because it is a pre-production model? Or do m43 cameras tend to do that when using AF with video? (Or maybe he was manually focusing?)

I'm considering replacing an HD camcorder with the GH4. The camcorder's AF never goes in and out of focus while shooting. That may be because it has a very small sensor (1/2.88), so the depth of field is high to begin with (which is a benefit or a drawback, depending on the situation). If this video is representative of m43 cameras when it comes to locking in AF, I may have to reconsider my interest in the GH4, despite all of the other virtues of the camera (including the ability to take great photos, which a camcorder can't do.)

Any comments would be welcome, especially from those who have used a consumer level camcorder and an m43 camera.

Thanks.
 
Definitely the GH1's continuous autofocus pulses in movie mode, especially with the faster lenses like the 25mm f1.4. It's the nature of contrast-detect autofocus that the camera can't tell whether it's achieved focus without comparing alternatives. To get the best footage, you have to shoot with manual focus. The GH4 has a new autofocus system, so the pulsing may be mitigated. But I definitely wouldn't reach any conclusions based on that guy's video.
 
noirist said:
Definitely the GH1's continuous autofocus pulses in movie mode, especially with the faster lenses like the 25mm f1.4. It's the nature of contrast-detect autofocus that the camera can't tell whether it's achieved focus without comparing alternatives. To get the best footage, you have to shoot with manual focus. The GH4 has a new autofocus system, so the pulsing may be mitigated. But I definitely wouldn't reach any conclusions based on that guy's video.
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As you mention, the GH4's new DFD feature of the autofocus may help. My interest in the GH4 is mainly for 4K video. The alternative for semi-affordable 4K is the Sony AX100 camcorder. Some of the wide depth-of-field focusing advantage of my current 1/2.88 sensor camcorder will be lost to the AX100's larger 1" sensor which, while smaller than the GH4's sensor, is still quite a bit larger than 1/2.88. I could use manual focus with the GH4, but I have gotten used to reliable AF with the camcorder. But I always use manual exposure with the camcorder instead of auto-exposure, so I guess I could get used to manual focus too.

I guess I just need to wait until both products are available for sale and user reviews start to appear. The big advantage for me of going with the GH4 is having excellent photo capability in the same camera used for video. As it is now, I carry a both a camcorder and a still camera with me when I travel. Getting down to just one would be nice.
 
dalemccl said:
... My interest in the GH4 is mainly for 4K video. ... the AX100's larger 1" sensor which, while smaller than the GH4's sensor
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If the AX100 uses the full width of the sensor (i.e. only crops height to get a 16:9 image from a 3:2 sensor), it will only be a little smaller than the sensor area used by the GH4 when shooting 4k video (which crops both width and height to get a 4k 16:9 image from a 16MP 4:3 sensor).
 
BitMaestro said:
smaller than the sensor area used by the GH4 when shooting 4k video (which crops both width and height to get a 4k 16:9 image from a 16MP 4:3 sensor).
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Maybe I missed something here, but why would it do that? You are correct that most camera sensors, especially those designed for stills, crop the height down to reach the proper rectangular shape required by the aspect ratio. But height AND width? What would be the point of cropping the width? It would just require you to crop the height again to match the new width, which sounds completely silly!

Note that not all camera sensor crop, a particular exception being the GH2 which famously got wider in video mode by using extra pixels on a multi-aspect sensor designed for just such a thing. That was great because you ended up with something much closer to the FOV of an APS-C camera that crops (7D, etc). I'm under the impression that they didn't do the special multi-aspect ratio again for the GH4 since no one has mentioned the wider FOV. But to assume it crops more than your average camera sensor by doing both height AND width? Why??

Meanwhile, a 1" sensor is a 2.7x crop, I think. That's pretty significantly smaller than micro 4/3.
 
M. Gilden said:
Maybe I missed something here, but why would it do that? ....But height AND width? What would be the point of cropping the width? It would just require you to crop the height again to match the new width, which sounds completely silly!....
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You did miss something here. It is basically doing an ETC function to get 4k from the wider sensor. They are doing this to eliminate processing. By going this way the camera only needs to compress the image rather than do any processing down to a smaller size then compressing. Panasonic has done a good job implementing their ETC function. Now they have just done it on a larger 4k scale. Pretty simple really. Cheers, Pete
 
c3hammer said:
You did miss something here. It is basically doing an ETC function to get 4k from the wider sensor. They are doing this to eliminate processing. By going this way the camera only needs to compress the image rather than do any processing down to a smaller size then compressing. Panasonic has done a good job implementing their ETC function. Now they have just done it on a larger 4k scale. Pretty simple really. Cheers, Pete
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Ah, thanks for that. Good info.

Well, that's a major downer for me. I'm still keeping GH2's around because I don't like the idea of losing more FOV, but the GH4 has enough going for it that I'm considering it (XLRs and focus peaking). But it looks like I'd be doing it for the 1080p recording only.
 
Uwe Lansing said:
They say shot in 4K on a GH4:

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I actually know the guy who shot this, and he did shoot it in 4k on a GH4. He said he had some issues with the camera though, and it shut off quite often. Probably beta bugs? Anyway, just wanted to verify that this video is legitimately shot on the GH4. I'm going to see the raw footage on Thursday night, which I imagine is much better than junk vimeo compression.
 
Has anyone read what battery this cam is taking? I'm really hoping it uses the same from the gh3, but welcoming higher capacity.
 
M. Gilden said:
Meanwhile, a 1" sensor is a 2.7x crop, I think. That's pretty significantly smaller than micro 4/3.
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I see c3hammer has already answered your main question. But since you asked me, I'll just add that the GH4's 4k ETC mode should add an additional 30% crop (i.e. increase to around 2.6X relative to a full 35mm 3:2 photography frame) which is why I said the AX100 might only be a little smaller.

OTOH, as has been noted multiple times in the other thread, downconverting 4k to 1080p should have significant benefits, especially with regard to luminance. (i.e. it should reduce shadow banding relative to 8-bit video.)
 
Thanks for posting both the videos. Detail and color are very nice. DR is just o.k. imho. But quite nice for a $1,500 camera body.
 
c3hammer said:
You did miss something here. It is basically doing an ETC function to get 4k from the wider sensor. They are doing this to eliminate processing. By going this way the camera only needs to compress the image rather than do any processing down to a smaller size then compressing. Panasonic has done a good job implementing their ETC function. Now they have just done it on a larger 4k scale. Pretty simple really. Cheers, Pete
Click to expand...
As I understand it, the GH4 only crops the frame for Cinema 4k mode. In regular 4k mode (ie., 3840x2160) there is no additional crop -- it uses the whole sensor width and has the standard 2.0 m43rds crop factor.
 
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