View Full Version : External recorder test: 1.1 firmware @25p


Josh Dahlberg
January 5th, 2012, 05:40 PM
Today I recorded ProRes 422HQ direct from the HDMI output of my Pal GH2 to an intensity pro card.

Various users have reported cadence issues with 24p output. My quick tests revealed no such issues at 25p. Very nice output! What surprised me is the additional image detail/texture in non-moving subjects. Close ups of the flower scene are at 400%.

My colleague's face is shown at 200%. The improved texture and detail is very apparent in the lips and freckles... overall the image has greater fidelity.

Given the non-moving target, and the fact HDMI out is crippled at 4:2:0, the improvement is better than I anticipated and very welcome.

Nigel Barker
January 7th, 2012, 09:05 AM
That is pretty convincing. I have been dismissive of those GH2 hack enthusiasts who have been claiming increased detail & resolution with the high bit rate hacks even with no movement but maybe they are onto something?

Josh Dahlberg
January 7th, 2012, 04:54 PM
Hi Nigel,

Yes, I actually set up the shot with the fan to test movement on the flowers - so the flowers are moving.

However the extra detail on the stationary phone etc surprised me, so I took a quick shot of my seated colleague... there's a big increase in fine texture/image fidelity.

I have to say, it's hard to spot a difference during playback on a 22" monitor at 100%, but blow up the image a bit and it's obvious.

It's enough for me to consider a Sound Devices Pix220, which would (in addition to onboard prores recording) will provide backup recording, monitoring and pro sound.

I won't be using the hacks personally as I'm petrified of something going wrong on a paid job. The Pix will give peace of mind.

Grading should be a step up too, but unfortunately it's only 4:2:0 output, a pity.

Steven Thomas
February 15th, 2012, 03:12 PM
The hack is now very close to HDMI raw out. Ralph_B has posted comparison shots of this data months ago. Also, it's quite apparent and seen with high detail and even more so with movement where the motion vector frames are starved for bandwidth.

It's really noticable in post. I posted frames a while back over at Viltaliy's site in differences between even 88Mb's GOP3 verses drifwood reQuainted GOP1 (i believe 150Mb/s). Even with these higher bitrate settings, the 150Mb/s had visibly smaller macroblocks which rendered more detail and less smearing.

Bill Bruner
February 16th, 2012, 04:53 PM
I'm a little confused by all the discussion of hacks. Josh's screenshots above are external recordings of a PAL GH2 w v1.1 of Panasonic's OEM firmware at 25fps, right?

Josh - did you use the Ralph_B AviSynth script or is this native?

Thanks and Cheers,

Bill
Hybrid Camera Revolution (http://hybridcamerarevolution.blogspot.com)

Josh Dahlberg
February 17th, 2012, 05:57 AM
Hi Bill,

Yes, I haven't used any hacks at all. This is native HMDI output from the camera - no modifications.

Unfortunately my camera was tethered to a Mac Pro in my office so I couldn't get out and about to test the setup as I'd like.

However, even in the handful of ad hoc tests I performed the difference was so apparent (and so compelling) I've asked the local Sound Devices dealer to send a demo PIX220 unit my way in the next week or so. The Pix with capture drive and batteries costs (and weighs!) four times more than the camera, so on paper it's a somewhat crazy proposition paring them.

But aside from vastly superior codec, it also adds professional audio and a half-decent monitor. I want to see how clunky it is: I'm already sold on the image quality difference offered via HDMI output, but I have to weigh that up against losing the lovely small form factor of M43.

The other option would be the much cheaper, lighter Ninja, but it doesn't have the same build quality, monitoring or audio.

Bill Bruner
February 17th, 2012, 05:54 PM
Thanks, Josh. Please let me know how it turns out. If it works, I'm thinking about renting a PIX240 from lensrentals.com for $239 for four days.

Cheers,

Bill
Hybrid Camera Revolution ("http://hybridcamerarevolution.blogspot.com)

Josh Dahlberg
March 17th, 2012, 06:22 AM
Hey Bill,

I finally got my hands on that Pix220 demo unit, for half an hour. Really nice to use. Footage looks superb.

The only downside is you lose focus magnification in the GH2 with HDMI enabled.

Also, any minor movement in the HDMI cable where it plugs into the GH2 port can cause signal loss, and a black patch in the recording. I didn't have a proper mount for the Pix220 while testing - if I buy one, figuring out a way to secure the HDMI cable at the GH2 port will be the #1 issue to address.

Please go to Vimeo and download the 1080p version if you want to have a good peek at image detail. I also explain settings there.

GH2 HDMI output 25p (in 50i wrapper) to Pix220 on Vimeo

Kevin McRoberts
March 17th, 2012, 09:44 PM
Have to admit that I also pretty much gave up looking for an external recorder solution after testing a few of the patches, for about the same problems you're mentioning: HDMI connector unreliability. Once you tack on the disabling of 720 and ETC modes, it kind of kills the utility (even in simple monitoring... grr.).

Of all the recorder solutions, the Pix units are the most attractive, if for no other reason than their XLR-in.

Martyn Hull
March 18th, 2012, 02:24 AM
So are we talking about the standard Pana aproved 1.1 update which i have or one of the Hacks which i dont in this thread. Of note 25P in pal recording looks superior to 24P IMO.

Josh Dahlberg
March 19th, 2012, 03:44 PM
That's right Martyn, just firmware 1.1 without any modification. I did try a few hacks with only limited success.

The HMDI output recorded to ProRes is extremely detailed, C300 level I would contend, and leagues away from every other DSLR.

Of course, dynamic range with the GH2 is much more limited than a camera like the C300, the shadows can still be a bit dirty, colour is restricted to 4:2:0, and the hdmi connection is fiddly to work with... but for the price the image is truly unrivaled.

Skip Marshall
March 19th, 2012, 09:12 PM
Josh, great images out of GH2 with your Sound Devices.

Thanks for posting the vid - downloaded the original and it really is incredible!

Are you using PIX 220 or 240? (seems that the difefrence is in HD-SDI plus Timecode on the latter.)

How heavy is the unit and how would you mount it on a rig with GH2?

May I ask what cadence issues were reported by other users (link, if possible)?

Thanks!

Josh Dahlberg
March 19th, 2012, 10:01 PM
Thanks Skip, Yes I'd encourage anyone interested to go to Vimeo and download the 1080 version - that's where you can really see the difference (and that's after it's already been converted to an H264 file for upload).

Actually I only had use of a demo unit for 30 minutes, so I just grabbed a few quick shots. It was a Pix220... the Ninja is a lighter, cheaper option that should deliver the same results. But with the Pix you get a nicer monitor, better build quality, and crucially, professional audio preamps/xlr inputs - so it's something that will outlive your camera and remain relevant for future DSLR purchases.

Another nice feature with the Pix is that it will down/cross-convert on the fly, so it does away with the GH2's 50i wrapper and records the footage as 25p.

The Pix is lighter than I thought it would be, but adds considerable bulk to the diminutive GH2. I had no cadence/image issues whatsoever (from memory with firmware 1.0 some users reported the frame rate output was inconsistent - it's perfect in firmware 1.1 in the Pal model anyway). Recorded to CF card and edited the files directly in FCPX.

I thought losing focus magnification would be a big issue... but it's not so bad as the Pix monitor is reasonable. The biggest issue, already noted, is reliance on the somewhat flimsy mini HDMI jack on the GH2. I had a loose HDMI cable swaying between the camera and Pix unit, and a few times this caused the signal to be lost.

If I decide to buy the Pix, I'm thinking of getting something like this:
K-Tek Norbert Accessory Frame KN2272 B&H Photo Video

But would still need to find a way to secure the HDMI cable at the GH2 end... that's the principal problem as I see it.

Other than that, the images are astonishingly detailed.

Bill Bruner
March 24th, 2012, 09:23 AM
Josh - thanks so much for doing the work to prove that the PIX with built-in pulldown removal works with GH2 HDMI output without a software mod (at least at 25p)! I am anxious to try it here in the States at 24p and 30p - but the least expensive rental I can find is minimum $239 for 4 days (http://www.lensrentals.com/rent/video/accessories/recorders/pix-240-video-recorder-256gb-ssd-disk) at lensrentals.com. Anybody know any SF Bay Area rental houses with a PIX 220 or 240 for less than lensrentals?

EDIT: Just found the 240 at videofax (http://www.videofax.com/forms/VFX_ratecard.pdf) in San Francisco for $175 a day! Really tempted to go check it out...

Cheers,

Bill
Hybrid Camera Revolution (http://hybridcamerarevolution.blogspot.com)