4K Chat

I guess you miss a bit of DOF with the sony...what do you think about the dynamic range compared to the gh4??

Without having both mounted on same tripod and shooting the exact same subject at the exact same time it really is impossible to honestly compare. A lot of reviews are trying to compare the cameras using different scenes and different changing light as well as different aperture, time, focal length of lens etc. These reviews are basically worthless. All in all they are both great new cameras. I am finding the AX auto focus to be very accurate. I've seen no color banding in the blue sky.

I have discovered perhaps a weakness in the AX-100 while shooting the moon rise the other night as it was coming up over a mountain ridge. Even with all settings set to manual, it introduced a brightness flicker on the subject (the moon) over time. However once the moon had risen and reached its full brightness it stabilized. Hence my suspicion is since the moon actually gets brighter as it reaches elevation, and even if all settings are locked down, the sensor still fights the bright spot (the moon). My settings were to capture the moon in correct illumination to capture the detail of it's surface. If I would have cranked open the aperture, it might have been better, but then it would just look like a bright blob. The prior night, I wanted to see how the camera would perform in all auto (except focus). This was horrible (as expected). It jumped around to the point that some frames even came out inverted, some drastically pixelated and some even popped up to look as if the camera switched itself to night shot mode. Very weird indeed.

It would help to tell the camera to take the exposure only on the moon but i don't know if it's so smart...:)..it sounds like that even in full manual it still keeps some automatism...

Regarding DOF of the AX-100 - it has great DOF when you open the shutter as well as in macro mode. I was really impressed by this. I like it.

The shutter????

Sorry I meant the aperture. Doh :)

Ya I believe even when in Manual mode it still leaves a little auto in. I did some zooms in manual and there was a slight exposure change on some of them as the zoom increased.

It acts like all lenses would that are not prime. As you zoom in and out, it changes the f-stop as the f-stop has limits based on zoom length. Reminds me of the 70-200mm L series canon lens as this is not a fixed aperture lens either. The aperture closes down as you zoom to keep the image sharp. It's too bad. Oh well, for the price one can not expect a fixed aperture lens on this camera.

Looking at the technical information on 4K clips taken by GH4 and AX-100 and comparing the Average bitrate. Knowing that different subject matter may affect it, this is just a quick comparison of a few different clips.

GH4: 544 Mbps, 208 Mbps, 130 Mbps

AX-100: 613 Mbps, 616 Mbps, 776 Mbps

It appears that the AX-100 shooting 4K UHD has a much higher average bitrate than GH4 shooting same mode.

For comparison 1080 HD:

GoPro 3 173 Mbps

Canon 5D MK III 168 Mbps

Sony Z-100 469 Mbps