Nice work. You hit on a lot of the things I've been saying on this forum for a while now.

@HenryO

The intent of this was that people can download the original files and show the differences that they see. If you could download the hacked and unhacked footage and post process it in the exact same way then we can see the same thing you are seeing.

Thanks for watching.

Can you summarize your findings? I view this stuff on laptops and smart phones and it all looks the same.
and thanks for doing this...

Downloading the samples now. The above samples from @WhiteRabbit illustrate how the macro blocking kills any good manipulation of the image but I will give an example from firstlight soon. @brianluce. Viewing it here on a full HD monitor and the difference is evident. The Hacked footage has a nicer finer grain where the unhacked has larger macro blocks. View on a large monitor if you get the chance.

Thanks for the diligent effort you put into these tests. I didn't find a link to your conclusions, could you post it here?

@No_SuRReNDeR

That is absolutely correct. There are benefits for each one of them. Now we have the ability to determine exactly what those are.

@LPowell

I didn't write them here. I just spoke them in the video. Here is the script I used for the video.

There are a few words I changed as I recorded it.

There has been a lot of debate lately about what is the best color profile to use and whether the hack can increase detail, color, and dynamic range. This video will attempt to answer all of those questions. Please remember to rate the video and subscribe to my channel if you want to see more videos like it.

I setup a test scene so that I could record the exact same thing for several different color profiles and several different firmware versions. The following tests will show the differences between the Cinema, Smooth, and Nostalgic color profiles as well as the differences between the new 1.1 firmware, the old 1.0 firmware, driftwood’s 187 mb/sec GOP = 1 hacked firmware, and the 42 mb/sec completely stable firmware.

In addition I have uploaded most of the original videos so you can download them and view them yourself. Just follow the links in the description.

First I want to show the differences between the Cinema, Smooth, and Nostalgic color profiles. Many people have claimed that the smooth and Nostalgic profiles offer the most dynamic range. That is actually incorrect. What they both do is boost the level of the shadows and the highlights equally.

This shifts the exposure up but it does not change the total dynamic range that is rendered. If you want to increase the perceived dynamic range then you have to use the Intelligent dynamic range feature which I described in the GH2 setup guide.

Now this doesn’t mean that smooth and Nostalgic shouldn’t be used. It just means that you need to use them in the right situation. The Nostalgic setting boosts the exposure more than Smooth which is great if you have a lot of underexposed shadows. However, the Nostalgic setting will blow out the highlights severely and it will add a yellow cast to the image.

The yellow cast can be fixed in camera with the white balance settings or in post processing. The crushed highlights cannot be fixed. Therefore I would go with the Smooth setting if you have large underexposed areas and you do not have many highlighted areas.

The other profile I want to discuss is the Cinema setting. It has largely been thrown to the waste side because of a couple of flaws. It tends to hard clip straight into highlights. This means that there is no roll off into the brightest highlights.

Look at the top of the toilet paper and notice how the Cinema setting clips straight into the highlight. While the smooth setting shows a more gradual roll off into the highlight. However, this does not mean that smooth is better for highlights.

Look at the giraffe’s nose. The Cinema setting clips much less than the smooth setting does. You can also look at the eagle in the $20 bill. The Cinema setting shows much more of the bird than the Smooth setting and it is almost gone in the Nostalgic setting.

The other big issue with the Cinema setting is that it underexposes about ½ of a stop. That is great if you have many highlights that you want to preserve. However, that could be very bad if you have lots of shadow detail that is essential. Either way you will need to correct for it in post processing.

None of these profiles are perfect. Maybe one day Panasonic or Vitaliy will give us a profile that will boost the shadows slightly, decrease the highlights, and leave the mid range as close to the RAW image as possible. That would be ideal.

The second part of this video will discuss the differences between the different firmware options including hacked and unhacked firmware.

First let’s start with the original 1.0 firmware that came on the camera. In 1080p @ 24 FPS mode it records up to 24 mb/sec variable bit rate H.264 AVC-HD. It offers a significantly higher maximum bit rate than the 17 mb/sec that the stock GH1 had for its 1080p @ 24 FPS mode.

However, this is a bit misleading because the unhacked firmware uses a very dynamic compression scheme. For low motion scenes like this one it will simply increase the compression to reduce the file size. For instance this 4 second unhacked clip is 6 megabytes while the max bit rate hacked version is 89 megabytes for the same 4 seconds.

I may be in the minority here but I just don’t have the time to upload files that are almost 15 times bigger. And once you recompress and upload them all of the benefit of the extra bit rate is lost.

Now this doesn’t mean that high bit rate hacks should not be used. They have a significant benefit in two areas. The high bit rate I frame only hacks offer frame by frame editing. All of the longer GOP hacks will prevent you from editing on anything but the I frame. This could be as much as a 30 frame difference. That could be very significant if you are doing 60 frame per second slow motion.

The higher bit rate hacks also offer much more accurate noise rendering. That might be desirable and it might not be. Depending on if you want a film like grain in your footage or not. It is hard to see in these examples because this footage has been recompressed at least twice.

The hacks also eliminate any compression artifacts that may be caused by motion in the video. These are static scenes so you won’t see any compression artifacts even in the unhacked firmware files. However, there are many examples out there that show how higher bit rates eliminate compression.

There have also been claims that the hack can increase color fidelity and increase dynamic range. I saw absolutely no evidence of that at all when I compared the original files.

Have a look at these samples and see if you can tell a difference. However, you really need to go and download the original files from the link in the description to see the benefits of the hack. Just remember that all of those benefits will be lost once you recompress the footage.

@WhiteRabbit

Great samples. I agree that there is no replacing the high bit rate GOP=1 for noise rendering and compression. It just isn't even close in that respect. However, there are times when I want to suppress noise. In camera compression actually does a better job at NR than the in camera video noise reduction does.

Have you guys seen this extremely scientific test that Kenw did that conclusively demonstrates that ISO 160 is the base ISO and that its multiples are pretty much the only ones you should use? It also shows that version 1.1 of the firmware does do some sort of noise reduction even for RAW files. Personally, I don't mind the v1.1 NR for stills. The v1.0 NR was absolutely unusable.

http://forums.dpreview.com/forums/readflat.asp?forum=1041&thread=40120298

@mpgxsvcd

Thanks for all the work on this careful testing!

Just one correction:
You wrote: "All of the longer GOP hacks will prevent you from editing on anything but the I frame. This could be as much as a 30 frame difference."
Sorry, any modern NLE will reconstruct the frames for a long GOP and you can edit on every single frame.

And one explanation:
The better noise rendering with high bitrate 1 GOP means two things: noise will not be "clumpy" (due to compression) and it will change from frame to frame and pixel to pixel. This helps massively with NR in post by good temporal reducers like Neatvideo. If you decide just to leave it (or reduce only to a certain percentage) it will look more organic, but only as long as you don't add another long GOP compression for delivery, like TV or Internet. But with high quality codecs like ProRes, DNxHD or Cineform, you can keep this grain-like quality throughout post and deliver it to cinema (in case you use the GH2 as a B-cam or even A-cam).

@nomad

Ok I didn't realize that. I will post a correction to the comments in the video. So why is it so many people wanted GOP=1 for editing if you can do the same thing with a longer GOP?

That's true, this is why we need so much computing power for native editing.

@mpgxsvcd
Because the image is better – far less macro-blocking :-)

The KenW research makes sense. Before I left town we went and metered a few different scenes and found out the GH2 is pretty accurate in video mode, give or take a hair on the stop. GH1 certainly was not.

If Powell is right, then perhaps 320 and 640 are optimal ISO values. I could stand to shoot 320 in broad daylight with NDs, which would mean a little less ND (a little helps a lot), but nothing less than that.

Also, I'd also agree with Powell that the changes in video operations should be factored in: I found 1000 ISO the very upward limit when considering a higher quality mastering workflow (denoising, DaVicini, etc).

Outside of ETC mode, I was pleasantly surprised to see 1600 ISO testing in a metered setting that called for 800 ASA Film and a stop of 2.8. A simple conversion of chroma noise to luma, then a very very mild denoise cleared up any issues I had with it.

Punching 800 up that far in post, however, would not be very pretty.