GH2 Practical differences between AVCHD and MJPEG?

DPStewart

DPStewart

Veteran
I tried searches but only found out of date info...

With a current stock or hacked GH2 - how should I understand the differences in image quality, motion quality, and "reasonable" data consumption between AVCHD 24P and MJPEG 24P (or 30P)?

(I already understand that MJPEG compresses every single frame and therefor uses more memory in general)

My main use for the GH2 will be production of music videos that will frequently have a lot of camera motion and/or subject motion.

THANKS ALL!
 
"a lot of camera motion" is not the strong suit of a DSLR. you sure you have the right camera for the job?
 
wgzn said:
"a lot of camera motion" is not the strong suit of a DSLR. you sure you have the right camera for the job?
Click to expand...

Ha! Yeah! - nothing like a Mountain Bike video or stunt videos! No, just more movement than interviews or movie-style drama.
Moderate pans and dolly motion.
Still mostly in controlled studio environments.
 
The key issue with MJPEG is files can't exceed 2GB. If you use the hack to get better quality, higher bps, you end up with less capture time. If this is OK for your application, MJPEG can yield excellent low light and good motion capture... Al
 
i often use mjpeg just because i like working with it. ive never done any A|B testing with both side to side...
 
You will be pleasantly surprised by the quality of MJPEG @ 100 mbps in the hacked GH2. I wouldn't say it's better or worse than AVCHD @ 50 mbps (hacked GH2). Image quality is much better than the MJPEG out of the hacked GH1...so the GH2 is doing something different/better than upscaling 720p to 1080p (as was the case in the GH1).

I use MJPEG @ 30p for some situations, and AVCHD @24p for others. The nice thing now (i.e. hacked GH2) is the difference in image quality is minimal and MJPEG is a viable option if required (e.g. 30p for faster movement). Some (read recent article on EOSHD) say that AVCHD has the advantage at high ISO's. It's worth trying for yourself to see if it suits your requirements under various conditions.
 
I would recommend you to stick to AVCHD with a good hack that is stable enough for your work. The MJPEG is a good quality but the problems are the 30p and the 2G limit blocking a lot of things (you may not be able to go through your entire track for the music video, run some tests)
 
Thanks all.
Consensus seems to be that unless 30P frame rate is NEEDED - that MJPEG does not offer any discernable advantages.
I appreciate the responses.
 
Although this is an old topic you might be interested to know that I've now gone over to using MJPEG exclusively for underwater work because it shows a lot less (i.e. virtually eliminates) the color banding issue which is a real PITA when using AVCHD ...particularly when there's lots of blue mid-water in the image.

I did a lot of A / B tests before shooting a documentary in West Papua for 4 weeks recently and now really like the color purity, better motion characteristics and NO BANDING provided by MJPEG.

Panasonic's implementation of H.264 in the GH2 is nothing short of a disgrace...as far as the color banding issue is concerned. I now realize it's not simply due to to a limitation of the hardware...i.e. an inexpensive camera. Totally unacceptable for even such a camera, hacked or unhacked. This is the only problem that let it down in the Zacuto shootout (the screening of which I attended in Australia). Color banding was very bad in the solid color wall of the set...something that critics of the GH2 in the audience (i.e RED Fanboys) jumped on with glee...

I hope that they seriously address the AVCHD banding issue in the GH3 or at least maintain MJPEG as an option.
 
Last edited:
The MJPEG mode saved me one time during a shoot. I had like 5 shots to go on a 72 hour contest and I ran out of space on my card. It was the last hour of sunlight I had before the contest deadline. I had a backup card that already some footage on it that I needed. When I shot with it, I got an error after one second. I knew it was because I had to format it to make the Driftwood hack work properly, but I couldn't because it contained some very crucial footage in it already from a different shoot. I thought I screwed up the entire shoot and starting feeling really nervous. Then I remembered the MJPEG mode which I had never shot with. I did a test and there was no error! Talk about dodging a bullet. In post, I had to do a 30p to 24p conversion, but it was only for like 5 quick shots, only two of which had any considerable motion. It cut in very well, and I don't think any non-DVXuser will notice haha. The MJPEG resolution was astoundingly similar to the AVCHD. The lesson here is to make sure your backup cards are freshly formatted if you're using the hack.

On another note, it would be cool to have 24p MJPEG mode on the GH3.
 
You must log in or register to reply here.
Back
Top