@LPowell

AVCHD is far superior to MJPEG in low light.

This is the case on the GH2 and has been so since the GH13. Here is a demonstration (full screen it). Even at 70Mbit versus 44Mbit, MJPEG is far noisier.



I don't like to see people waste their time on something that's so obviously as flawed a concept as 'an MJPEG low light patch'.

If you shoot in low light at high ISOs on the GH2 stick to AVCHD, period.

Remember also that MJPEG 1080p is basically upscaled 1280x720 and 30p, whilst AVCHD Is true 1080p at 24p. That is a huge difference especially the cinematic frame rate.

Maybe someone will do a comparison between GH2vk MJPEG and AVCHD? Its great to have hi bitrate in MJPEG as an option, but I shoot mostly in 24p, so curious to know how it compares.

EOSHD: "I am sorry but this is a total brand exercise"

Thank you, EOSHD, that is a real compliment coming from someone who has demonstrated mastery in the craft.

While AVCHD is a more sophisticated encoder than MJPEG, many of its most efficient compression techniques rely on coarse quantization of image details that it considers insignificant. Unfortunately, dimly-lit shadow detail is one of the aspects of image quality that Panasonic's AVCHD encoders appear to shortchange. At its heart, the GH2 is a consumer camera tailored to produce pleasing results straight out of the box, rather than a high-precision motion capture device designed for a post-production workflow.

MJPEG videos tend to have a grainier look due to the relatively finer degree of image filtering used in their quantization tables. Some might even consider MJPEG "noisier" than AVCHD, but that's because of MJPEG's tendency to expose more of the image sensor's raw behavior.

According to cbrandin's recent investigations, the AVCHD encoder's highest quality quantization factors used for shadow detail are around 18-20. The quantization tables used in the 100Mbps GH2 Low Light MJPEG 1080p Patch apply similar degrees of quantization to properly-exposed areas. However, as illumination decreases, the MJPEG encoder automatically uses finer quality quantization tables in dimly lit frames in order to maintain the high bitrates this patch is optimized for.

Here are examples of the quantization tables used in two of my MJPEG sample files:

Monument, GH2 MJPEG 1080p @ 1/60 sec:
Destination ID=0 (Luminance)
DQT, Row #0: 7 7 7 7 20 13 33 33
DQT, Row #1: 7 7 7 7 13 26 33 33
DQT, Row #2: 7 7 13 13 13 26 46 39
DQT, Row #3: 7 13 13 20 33 39 59 59
DQT, Row #4: 7 13 20 33 39 46 33 65
DQT, Row #5: 26 20 33 39 46 59 46 59
DQT, Row #6: 13 39 52 46 59 65 59 52
DQT, Row #7: 39 46 52 52 65 65 59 59
Approx quality factor = 71.42 (scaling=57.16 variance=202.70)

Monument, GH2 MJPEG 1080p @ 1/500 sec
Destination ID=0 (Luminance)
DQT, Row #0: 3 3 3 3 9 6 15 15
DQT, Row #1: 3 3 3 3 6 12 15 15
DQT, Row #2: 3 3 6 6 6 12 21 18
DQT, Row #3: 3 6 6 9 15 18 27 27
DQT, Row #4: 3 6 9 15 18 21 15 30
DQT, Row #5: 12 9 15 18 21 27 21 27
DQT, Row #6: 6 18 24 21 27 30 27 24
DQT, Row #7: 18 21 24 24 30 30 27 27
Approx quality factor = 87.05 (scaling=25.91 variance=44.05)

The upper quantization table was used to encode the overexposed take of the Monument video, and the lower table was used on the underexposed take. While both tables indicate high quality results, the quantization factors used in the dimly-lit take are less than half as coarse as those used in the brightly-lit take. This is exactly the type of encoder behavior that's desirable for preserving low-light shadow details.

I like the "raw data" from the sensor with MJPEG - like film grain from a 35mm Kodak Filmcam
;)

Shooting one in 10 mins time with Nokton F0.95 and Canon 50mm F1.2

Using GOP 6 on the 42Mbit AVCHD mode. Any reason to keep GOP at default?

Testing so far reveals AVCHD still looks nicer in low light than this MJPEG patch. Same camera, same lens, best to choose right settings for the task, no?

@cbrandin totally agree! But it has to be said. Shooters should choose appropriate settings for the job.

There's such a huge array of confusing MJPEG patches out there with so many different flavours when 2 or 3 will do and none of them are currently suitable for low light shooting.

@EOSHD I don't understand why you are committing character suicide? I used to like you and look up to you; Now, for the past few weeks, you've been a total ass with the GH2 hack and LPowell. Is everything ok? Why are you so negative?

EDIT: I'm not trying to make you feel worse, I'm genuinely worried. I myself have had a "burnout" because of work, I know the feeling. With all good in my heart, maybe you shoud take a few weeks off? You are respected in the community, please don't continue in the self destructive path you've now seem to take.

So it is better in it's current form with this patch than AVCHD 42Mbit at ISO 1600?

More detail? Less noise?

I don't think so. Moving MJPEG forward in a significant way will not happen with these kind of patches. I'm sorry but it IS a waste of test time.

It's like a racing team on the edge of a great leap, with 1 hour remaining at a test session, and deciding instead to fiddle with the wheel nuts.

"He didn't seem THAT confrontational."...as long as you're not one of the blind idiots he's referring to....

I've just done a quick low light A/B test (artificial flowers indoors, natural window light):

1600 iso; GH2 AVCHD 35/30 settings (clip was 34mbps) ; MJPEG (clip was 93mbps); 14mm pancake.

Playing both clips side-by-side (i7 Sandybridge; twin monitors)...my impression:

MJPEG is excellent...grain about the same for both...detail rendering about the same...color rendition similar (but MJPEG whites seemed slightly cleaner). Overall very usable. I prefer the MJPEG image in this particular low light test.

This was one test...for my own curiosity. MY conclusion is that MJPEG from the GH2 using these settings is excellent. Please test for yourself and make up your own mind...

MJPEG LPowell Low Light test at ISO 3200 with Canon FD 50mm F1.2L.

- MJPEG has higher noise overall
- Sadly it also has lower detail so you cannot run Neat Video to win back detail as effectively as you can with AVCHD 1080p
- MJPEG has pink tint due to less noise reduction in the red channel
- There's coloured moire on fine detail (Look at the hand grip of 600D and around the EOS badge lettering)
- It's 30p and I much prefer cinema 24p

Judging noise from stills is not the whole result, the way the noise fizzes over the image is also relevant. Will post final video results on blog later in the week. For now need to get back to work.

I want MJPEG improved like you all do, it has fantastic potential but this MJPEG bitrate stuff has been done to death now. This is one helluva distraction guys.

LPowell: "The MJPEG encoder also excels in difficult low-light conditions where the AVCHD encoder cuts down its bitrate to minimum quality levels."

In theory but clearly not in reality. Look at the smoothness of the gradated tones over the lens release notch on the 600D in the AVCHD shot compared to how it looks in MJPEG mode with the LPowell Low Light patch.

AVCHD at 1:1 crop:



MJPEG at 1:1 crop:



Full frames attached.

Here you are.

To stay on the topic of preferences...Here's a video that showcases rolling shutter. All filmed on an iphone4. "Shortcomings" can be useful if you think outside of the box. It all boils down to preference. Video just wouldnt work as well or be as pleasing if everything was "perfect".