GH2 Help with external recorder and follow focus

[wgzn]

The problem is that basically the quality is there, camera factories just do not allow using it.

well, from a business standpoint, it goes to reason that if you had the holy grail in your hands. you might release it in small bits in order to prolong your market.

i have to wonder what canon may be doing with the fiscal train-wreck that is the c300

so apparently RED is the only company that gets it?
ok. i'm in. ; )

 

[M. Gilden]

You will not get better color sampling from an external recorder, because the GH2 doesn't actually output 4:2:2. In fact, you'll have more hassles because the GH2 outputs a "broken" chroma and you'll have to run a VirtualDub script on every file you record, in order to un-break the chroma and restore it to normal 4:2:0.

Feel free to correct me if I'm mistaken, but I believe I've seen threads and blogs that claim the fixed output is actually 4:2:2.
The general speculation is that the broken chroma was put into place to disable the higher color recording on purpose, so that people would not try to do this on a budget camera (instead you get a "broken" 4:2:0). I have no idea whether or not this is true, but my understanding is that recording the HDMI out and running those VirtualDub scripts does in fact yield 4:2:2 and not 4:2:0.
Although for general shooting, I'd have to agree that running the scripts and putting all that extra effort into post for an arguable bit of extra color definition does not seem like a worthwhile workflow. But for certain visual effects, it might be a different story.
I know at least one post processing house insisted on doing this to pull a better key.

 

[j1clark@ucsd.edu]

The problem is that basically the quality is there, camera factories just do not allow using it. If more people demanded unlocking the full potential, we would get it eventually. Twenty thousand dollar cameras exist but they are seldom going to be on hand and ready when opportunity for some filmic recording present themselves. Magic hour does not last one hour and it does not necessarily occur every day. When it does, you will want to capture and immortalize it at the best possible quality.

Unless the demand counts in the 10's of millions, and Panasonic shifts the GH-X series into the 'pro/simi-pro' line... you can forget it... wait they have something in that arena... the AF100...

 

[Aki_Hartikainen]

All that would be needed was a gigabit class SDI output on the GH2. Then the option to record 4:2:2 would be easier for those who want it.

 

[duder1234]

That would be a nearly impossible nightmare. The color that gets output on the HDMI port doesn't match the color that the camera records internally. I'm not talking about color sampling, I'm talking about the color itself -- the HDMI output just isn't accurate. It doesn't accurately display the image the camera is creating.

If the HDMi out doesn't match what the camera is recording, then how does one go about viewing the "recorded image" while shooting? Is an external monitor (perhaps a marshall) a no-go with this kind of camera?

 

[mr bill]

Import something you've shot into your editing system. Play back the same file on your calibrated monitor and on your GH2. Match the lcd display as closely as you can to the calibrated monitor. Do the same with your external monitor, and you'll have something useable on location.

 

[M. Gilden]

If the HDMi out doesn't match what the camera is recording, then how does one go about viewing the "recorded image" while shooting? Is an external monitor (perhaps a marshall) a no-go with this kind of camera?

For things like judging composition and focus, its great. The color just isn't accurately represented.

There's a well known bug with the GH2 that the color seems to shift ever so slightly as soon as you hit record, even when using the internal display. You just have to learn how to work with it.

Meanwhile, everything I'm seeing appears to point to the corrected HDMI signal being 4:2:2 color. Barry, I see you are even quoted as describing the GH2's HDMI out as "screwed up 4:2:0", yet Marvel's experience with a Atmos Ninja (as well as testing by Jorgen Escher) have shown that a full 4:2:2 is hidden inside that.
More on that here: http://marvelsfilm.wordpress.com/2011/04/19/panny-gh2-hdmi-recorder-bingo/

I don't have a Ninja or other compatible HDMI recording device (only certain devices seem to work with these scripts), so I'm not really in a position to test any of this myself. Nor do I really feel the need to- I'm personally fine with what the GH2 records. But I does appear that the option to get 4:2:2 out of the camera is there.

 

[Aki_Hartikainen]

If you are interested, finished GH1 grading test movie that I used as example on the previous page is now online at: http://www.youtube.com/watch?v=YUtwOrH5_SM

Grading started already on location using a color filter on the lens. In post it would have been difficult to pull good blue hues from limited color resolution. Comparison to Hollywood DVD's shows that resolution of the graded version is already on par or slightly better than DVD. So only a slight improvement in color resolution would give more flexibility in post and put us in the business of making movies. Perhaps not block buster movies, but you get the idea. Another note, using MJPEG codec as a source for upload improved quality on YT. It also made the film a bit more contrasty and saturated than intended, but this can be easily compensated the next time.

Links to full size frame grabs, if anybody is interested:
http://www.fourseasonshd.com/EndHibernation1large.png
http://www.fourseasonshd.com/EndHibernation2large.png
http://www.fourseasonshd.com/EndHibernation3large.png

 

[ulisses]

All that would be needed was a gigabit class SDI output on the GH2. Then the option to record 4:2:2 would be easier for those who want it.

That should be the AF100... high quality SDI
Maybe should be better to record in the internal GH2 SD card. I was thinking in PRORES to save time editing, but re-process it before editing doesn't make sense.

Thanks,
Ulisses

 

[Aki_Hartikainen]

I think I will have to look at AF100 next for a bit more filmic grading. Quality I get from GH1 and GH2 in most cases is close, though. It just lacks finesse. I would especially like clean shadows with some gradable hues and not stretch the black very much, which seems to be the prevalent "film look" these days. I've noticed that if the material needs a lot of preparation, I tend to procrastinate on the job. One way around that would be to have an assistant to do all the preparations for the material.

 

[Gary Huff]

I was thinking in PRORES to save time editing, but re-process it before editing doesn't make sense.

Yes, no matter what you do, you will still end up having to process the video clips.

 

[M. Gilden]

That should be the AF100... high quality SDIMaybe should be better to record in the internal GH2 SD card. I was thinking in PRORES to save time editing, but re-process it before editing doesn't make sense.Thanks,Ulisses

That will never happen. Prores is proprietary to Apple, which means not only would panasonic have to license the codec, it also wouldn't work on nin-final cut editing systems. As an Adobe CS5 user on PC most of the time, I hate when a client gives me Prores footage. A royal pain to work with on any other NLE.

 

[ulisses]

That will never happen. Prores is proprietary to Apple, which means not only would panasonic have to license the codec, it also wouldn't work on nin-final cut editing systems. As an Adobe CS5 user on PC most of the time, I hate when a client gives me Prores footage. A royal pain to work with on any other NLE.

I was talking about PRORES in external recorders, to save time when editing in FinalCut...

 

[M. Gilden]

I was talking about PRORES in external recorders, to save time when editing in FinalCut...

Ahh- sorry, I misunderstood your post!
"high quality SDIMaybe should be better to record in the internal GH2 SD card. I was thinking in PRORES to save time editing" ...I mistakenly assumed you were sharing how you wished the camera worked (High quality SDI or perhaps recording better quality in prores to the internal card).

Ideally, your idea would be great- recording HDMI into a prores recorder- but as we pointed out in this thread, the GH2's "clean output" is a borked 4:2:0, with a chroma channel that needs to be repaired with extra processing scripts. So, either way you will need extra steps out of the camera, effectively eliminating any saved time.

That being said, you would get the added benefit of possible 4:2:2 with the right scripts and recorder. But that might not be what you are looking for.