GH4 4K>ProRes 1080p Path

Michael Erlewine

Michael Erlewine

Well-known member
I have not owned a Lumix before, and have been doing much of my work on the FS700 and the BM Pocket Camera. Ordered the GH4 for use with a camera stabilizer (Helix from LetusDirect).

Sorry for my ignorance. What I want to get is 1080p from 4K, but I am confused whether (and how) this can be done in-camera. I understand I can port the signal out to an external recorder, but not sure what recorder can receive a 4K>ProRes HD. I have the Pix220i and the Odyssey 7Q external recorders.

I am looking for ProRes quality. If one of you know the path to this off the top of your head, please let me know.
 
The upcoming Atomos Shogun is what I will be using when it starts shipping.

FWIW, I have been shooting 4K internally and then bringing that footage into a 1080 timeline where I can scale the footage appropriately.
 
The Shogun is on my radar, but I am new to the Lumix. What can I do right now for the best resolution for finished 1080p footage?
 
The AJA KiPro Quad is currently the only external recorder that can capture the 4K 10-bit 4:2:2 coming from the GH4, but only if you use the YAGH add-on for its four HD-SDI outputs. The Atomos Shogun is currently the only external recorder that can capture the 4K 10-bit 4:2:2 coming from the GH4's HDMI output (no need for the YAGH add-on) but it's not shipping yet. The people I spoke to at the Convergent Design booth at NAB this year told me that it's possible they may upgrade the capability of the Odyssey 7Q to handle the four HD-SDI from the YAGH but unlikely that they can handle the GH4's HDMI.

So right now the best way to get best resolution for finished 1080p from the GH4 is:

1. Use a super sharp lens (Lumix primes produce good results)
2. Record 4K 100Mbps in camera
3. Either transcode the original files into 1080 ProRes422 or just resized them in your timeline.

I tried both approaches and I couldn't see a difference in quality between them. I'll be posting a video comparison soon.
 
I'm having good luck using Mpeg Streamclip for resizing 4k to 1080 for now. Looking forward to seeing what 5dtoRGB comes up with, as that's what I use for all other files from GH2/3/4/GX7/G6.
 
I head from Sound Devices support team that the Pix 220i that I have will work with the Lumix GH4 for ProRes level. Just set the Pix 220i to HDMI. Have no idea what has to be set inside the GH4.
 
Cosimo Bullo said:
I'm having good luck using Mpeg Streamclip for resizing 4k to 1080 for now. Looking forward to seeing what 5dtoRGB comes up with, as that's what I use for all other files from GH2/3/4/GX7/G6.
Click to expand...

I'm not use to transcoding any footage from my GH3 before editing. I have heard a lot of people talk about 5GtoRGB and Mpeg Streamclip or neat video. Does this even make a difference in quality? Would it be any different than just dropping my original GH3 footage into after effects and exporting as proress or lossless?
 
Michael Erlewine said:
I head from Sound Devices support team that the Pix 220i that I have will work with the Lumix GH4 for ProRes level. Just set the Pix 220i to HDMI. Have no idea what has to be set inside the GH4.
Click to expand...

The Pix 220i may be able to record a 1080 stream from the GH4's HDMI output, but I'd be surprised if it could record a 4K stream from the HDMI. If you run any tests then please report your findings.

gutterball321 said:
I'm not use to transcoding any footage from my GH3 before editing. I have heard a lot of people talk about 5GtoRGB and Mpeg Streamclip or neat video. Does this even make a difference in quality? Would it be any different than just dropping my original GH3 footage into after effects and exporting as proress or lossless?
Click to expand...

I just posted a video comparison showing that there's little-to-no difference between these two approaches. Here's the thread:

http://www.dvxuser.com/V6/showthread.php?323037-The-Best-Way-to-Convert-4K-to-1080
 
Hi

gutterball321 said:
I'm not use to transcoding any footage from my GH3 before editing. I have heard a lot of people talk about 5GtoRGB and Mpeg Streamclip or neat video. Does this even make a difference in quality? Would it be any different than just dropping my original GH3 footage into after effects and exporting as proress or lossless?
Click to expand...

It does not improve output, if anything it will be worse. I think many people have the idea that the editing takes place in the codec that the video is encoded in, but it doesn't. Whatever is on the time line is decoded to full uncompressed video frames a few at a time, edits made to each frame, then they are recompressed to whatever the output is set for.

So going via ProRes first just adds an extra lossy encoding step, visually lossless maybe, but lossy all the same. Of course if you start out capturing straight to ProRes from the camera sensor, then it makes sense to keep it that way.

The only benefits I can see transcoding to ProRes first are that it would be easier on the software/hardware when editing, or maybe you have to as the editor will not accept the native files.

Of course ProRes is a good common format with excellent quality to move files between different software packages or pass to others for further editing, but you can still do this, just use native files on the first link in the chain then export as ProRes, you get first generation ProRes then at that point, rather than second generation.

Regards

Phil
 
Many of us are still using timelines that need the transcode (FCP 7 for example). Prores HQ makes a good middle ground of quality and speed. Probably time to switch to premiere and edit natively, but I'm used to the workflow and busy, and so it's hard to make the change.
 
Hi

Cosimo Bullo said:
Many of us are still using timelines that need the transcode (FCP 7 for example). Prores HQ makes a good middle ground of quality and speed. Probably time to switch to premiere and edit natively, but I'm used to the workflow and busy, and so it's hard to make the change.
Click to expand...

I know what you mean, once used to something it is hard to make the switch and start again with another package when the end result is as good as the same.

Regards

Phil
 
Cosimo Bullo said:
Many of us are still using timelines that need the transcode (FCP 7 for example). Prores HQ makes a good middle ground of quality and speed. Probably time to switch to premiere and edit natively, but I'm used to the workflow and busy, and so it's hard to make the change.
Click to expand...

Thanks for the tips. I edit in FCP7, fCPX and Premiere depending on where I am when I edit (on the road, work, my house). I have noticed the exports in FCP7 are worse and the exports in FCPX are the best even when saving the same codec/container and file sizes. I can't add vignettes to title screens/graphic logos in FCP 7 because it turns the vignette into rings instead of a smooth gradient. This helps explain that a little
 
Even on modern NLEs that support native H.264 editing (FCPX, Premiere), I still find it's worthwhile to transcode to an intermediate codec as applications like Resolve still don't handle H.264 well.
 
You must log in or register to reply here.
Back
Top