That is very convincing. Can you state the file sizes, or bit-rates, assuming both videos were shot identically except for the NR setting.

Thanks for confirming this. I've also noticed that having the in camera NR set to zero results in a strange inconsistent red heavy flickering noise pattern which is pretty much impossible to remove. I quite like it (but I'm weird) and played with it a bit recently, I used Nukes deflicker node to deal with it as any kind of denoising isn't going to do much with it at all. The flicker is more obvious in the original file if you download it.

Could you try the same test with Sharpness and Contrast? I would like to see how those affect the specific test you are doing. I would expect all of them to negatively affect the image except maybe contrast. I still have not totally figured out how that setting works.

@Ptchaw You may have missed a post by @cbrandin about how a bit of on camera noise reduction will in fact yield better quality in the end. If I recall correctly his argument, some noise correction in camera will free bits that normally go to compress noise accurately to be used for more accurate compression of what is important in the image. His idea is that if you are going to remove the noise in post, the camera wasted bits compressing the noise. Any noise comparisons really should be done after doing post on the image to make decisions... Al

Chris is right assuming the end results using the in-camera NR are good enough.
The problem i'm seeing is the current GH2 in-camera NR will never be good as post solutions.

Also, it would depend on where in the signal chain their NR takes place.

One last thing, all noise reduction programs cause "some" loss of detail. Some programs are just better than others. The in-camera soultion has no control of what it thinks is noise. It's a one button knob. Programs such as Neat Video have a lot of control with many parameters.

+1
Stray.
You are absolutely on the money with this one!

@cbrandin I completely agree, it is an area that needs a lot more testing. Also, yeah, the noise is obviously going to busy the codec more. But I feel its going to be down to each persons individual workflows, their aesthetic needs, and each shot, judging from the NR and noise removal experiments that I've done. Because of that I feel we're not going to reach any kind of consensus other than 'its something to consider when shooting at higher ISOs'. So its something for each of us to test I feel, and to come up with something that we're happy with individually. As I discovered with my test above (one of many I've done with in camera NR and various noise removal methods in post) I found something with in camera NR that I liked, which I'm pretty sure noone else here would, or would tolerate (the denoising flicker). Also that kind of thing is not something that can be removed easily with just denoising in post. I also found with that shot that shooting with NR set to -1 was pretty ugly, subjectively to me the shot with it set to zero was the best and the one I felt like working with. Shooting at +1 or +2 it looked terrible to me.

My original guess about the in camera NR filter was that it was a cheap and cheerful linear smoothing filter, however that wouldn't to my mind create the flicker we're seeing (unless it is a 2 pass process with linear smoothing being in the second pass). What would would be some kind of median filter where its getting the intensities wrong somehow under certain conditions. The fact that the flicker always has more intensity in the red channel, and that, as said in other threads, this camera is more noisy in the red channel is a worry. Surely Panasonic would know that its at it's worse in the red and would weight their NR algorithim accordingly. Or maybe they are, and that, coupled with higher bitrates, is causing the odd flicker on certain shots when the NR throws incorrect intensity values. Also its hard to know if the stress of runing the camera at higher bitrates is itself effecting the abilities of the in camera NR (though it probably isn't, I'm guessing).

I'm lucky when it comes to denoising in post as I have a few options, from PFCleans approach, to Neat Video and finally Nukes new wavelet based approach. Each produces different end results under different conditions, and the choice of which, and the solution I end up being happy with is subjectively mine. I don't think myself that any in camera NR is going to be acceptable to those who do NR in post, as what it does is to create something thats more difficult for any post NR tool to deal with. I said 'I don't think' at the beginning of the sentence, I do agree that more tests need to be done here. Thing is though NR is full of vagaries. I've never found that I've got good results running footage thru mutiple NR solutions in post (unless one of the NR approaches I've used in the chain is used in a really, really foccused way; as in linked to a single colour channel, or to a single band of noise frequency), it usually just creates problems further down the NR chain. So the idea of doing a little in camera followed by doing more in post fills me full of dread as to the problems people are going to get doing that, these will be a serious of image grabs and Neat Video settings I don't think I'm going to want to see ;) .Its just going to confuse more than reach a conclusion I reckon. Stick to what @proaudio4 has done at the start of the thread, strict in camera NR comparisons at different ISOs and bitrates, thats information we can use and react to usefully.

If been shooting various tests at 66mbps going through the whole range of NR at 1000 and 2000 iso... and found generally that -2 produced a more even tone of grain... as opposed to the other NR settings which tended to cause the noise to dance around the screen drawing more attention to itself... but who knows under some circumstances +2 NR might look great, its nice to be able to test the location and lighting if you have the time, but in a push I'd prob leave on -2 and remove noise with software.

Stray,
I'm fairly sure this test was at 0 for both Contrast and Saturation.
Interesting find on your end.
I'll have to do more testing with contrast at 0 verses -2.

@cbrandin Yep agreed, what I'm saying is it seems from what I've seen that the contrast in the scene, and the contrast setting in camera has a strong effect on how the in cameras NR performs. If you do set contrast badly, as you say clipping the dynamic range, there is more chance of flicker and the results out of the in camera NR get a lot worse. This isn't a surprise really, and I've no idea why I didn't test it before (probably because I'm trying to tweak with the camera at the same time as working on a project, can't help myself, it's just too interesting), as NR post routines exhibit similar behaviour too.

Are we are talking about low lighting case?

Normally I don't wanna jack up the ISO too high. I'd rather get underexposed clips. When I boost midtone gray during PP, ugly noise become more visible.

Saturation -2. It's underexposed in the first place. I wouldn't get great color. Just suppress it to keep the color noise down.

Contrast -2. I wanna keep the midtone gray details more in this case. Crush the blacks during PP.

Sharpness -2. It's not properly exposed. No need to depend on in-camera sharpening in this case.

NR -2 or -1. Low lighting again. Less details to render. Possibly more noise reproduction might help in this case.

Hello All,

This manual is better than nothing, but it doesn't have everything in the contents or index so finding information is difficult (not intuitive).

I see a setting for "Long SHTR NR" but that doesn't function while shooting movie clips, so that's not a factor.

Where do you find the settings for the internal NR?

Thanks!