Is there Posterization on Japanese GH2 also?

[AtticusD]

I have had my GH2 for 3 1/2 months and I have not seen one instance of posterization. Maybe it exists in your camera, or maybe not. There are so many variables that come into play - how the picture is being decoded on your computer, what software is displaying it, the graphics card or chip and it's settings, even the computer monitor itself. Any one of these could be the cause.

To cut through all this muck, do this simple test. Take an HDMI cable and plug your GH2 directly into a TV. Play a clip that you think has posterization, from the SD card in the camera . If posterization appears on the TV, then it's for real. If not, then the problem is somewhere in your computer's "food chain".

Thanks for the advice. I'll try to plug the camera directly into the TV just to be sure. But the thing is that in the first two months with my GH2 using mostly the 20mm pancake and a Canon FD 50 1.4 I failed to notice any instance of posterization (not that I was looking for it). The moment the Voigtlander 0.95 arrived I made a quick first video with extreme close shots of a bunch of toys and the lens wide open and there it was, posterization galore. From then on, I started to see the nasty effect in other places though most of the time is so subtle it doesn't bother me that much. So it can take a while to notice posterization in GH2 shots and depending on the kind of work you do, you may never notice it (well, most probably you'll do sooner or later).

The GH2 is a great camera, don't get me wrong but I still think that Panasonic should figure a better way to deal with potential posterization. I mean, far worse cameras have done a better job to hide posterization in the past, it's ridiculous that the GH2 can't do it. The overall quality of the image is so amazing that this effect stands out even more, like it was pasted over the image.

 

[roei z]

The noise solution can also be adding it as film grain on the final sequence?

 

[AtticusD]

The noise solution can also be adding it as film grain on the final sequence?

I think so. You should be able to add some film grain to the portion of the clip in your final sequence that has posterization and minimize the problem. Maybe someone more experienced could suggest a better workflow/solution...

 

[j1clark@ucsd.edu]

If posterization appears on the TV, then it's for real. If not, then the problem is somewhere in your computer's "food chain".

Not true. LCD TV's have a spec, sometimes not well indicated, of bit depth. You could have a TV that has a lower bit depth, say 8 bits per R, G, B, and get 'banding' on images with smooth gradients. The use of the extremely shallow DoF, actually contributes to the likelihood of observing 'smooth gradients', as items that are in front or behind the plane of sharp focus will be 'blurred', and thus potentially give rise to 'smooth gradients'. A wall that formerly had texture, and light fall off, that is
a gradient from the light, once the texture is blurred, will have a 'smooth' gradient from the fall off, and this have a higher likelihood of inducing the phenomenon.

About a year ago the Daughter was using some of the Parent's Fuji S2's and called up 'worried' about her images that included some sky, and with converting the images to B&W, she began to see hints of 'banding'... she thought the camera
was defective... no... JPEG and 8-bits on smooth gradients... even at the highest spatial resolution, and the highest JPEG quality...

I tend to not use extremely shallow DoF, so, I typically would only see this in shots that have nearly black sky, perhaps less water vapor to give a 'deep' blue towards zenith, and a lighter blue at the horizon, and a rare occurance in my
region, since even on hot days the sky is pretty 'light' due to water vapor...

Oh, yeah, while I'm at it.. I will also note that dust on the sensor is most noticeable on these sorts of shots as well... in fact you can tell how good the cleaning of the sensor is by pointing the camera to the 'north sky', on a clear day, opposite the sun, and get a 'smooth' near monochrome, then to through the images in Photoshop to determine if there are any dust spots, clean again, and if the 'spots' remain, perhaps think about camera service...