HDMI Capture Problem SOLVED - AviSynth RULES!

This is happy knews! Can someone say the file size hdmi makes? We got 24 Mbs incam, how in hdmi?????
 
ghosttv said:
This is happy knews! Can someone say the file size hdmi makes? We got 24 Mbs incam, how in hdmi?????
Click to expand...

The data rate depends on which codec you use for capture. For example, Blackmagic's MJPEG codec runs around 13.5 MB/sec. UT lossless 4.2.0 (which I used in the capture on the previous page) runs around 30 MB/sec. That's ten times more data than AVCHD, which runs around 3 MB/sec.
 
Up to a certain point can be worth, it just depends on your project needs. Useless if you'll spend MBs in vain :-) but just for the record, now you can get broadcast standards in a glance for $1,000 with a GH2 (I'm paying €500) + other $1,000 with Atomos [ LINK ], not worthy? ;-)
 
And here I thought the AVCHD was good enough (it is) but look at the detail difference you get straight out of the HDMI. I told you so. Still....it's amazing how much you get back in shadow detail out of the HDMI. The camera was already sharp enough....now....whoa!! Having 4:2:2 would be nice....for greenscreeening etc. (I'm sure it will hold up just fine with a less compressed 4:2:0) but for all other applications....this is gold.

I bet this camera will take off where the 5Dll/7D/T2i left off in popularity. This kind of changes a lot of things. It's now an even greater companion for the AF100 (or whatever).
 
Great work Ralph

It's like there is more dynamic range too, or is that the effect of more shadow detail? I notice it even in the lower mid tones
 
Is it me, cause I am seeing a little bit more noise in the hdmi version. I think the Avchd compression is acting as a noise reducer. As it smears the detail, it smears and also reduce the noise. It would be nice to see the base iso image to get a good idea about it. We should not forget that the gh2 is a photo camera and that it is at the base ISO that you get the cleanest noise. It should not be compared to the Sony F3, Alexa or Red Mx who have base Iso in the 800 range.
 
I think you're seeing more detail in the dust/particles. All of that goes to smudge when it hits the AVCHD compression. You're also seeing finer grain in the uncompressed capture...
But yea, the compression is kind of acting as a noise reducer but it introduces compression artifacts also. I'd rather have the finer grain/more detail than the smear/smudge/compressed look.
 
I was not complaining about the hdmi output, in some way I think it is a little revolution and a milestone in the dslr video. It is the first dslr to get uncompressed output !!! For now we are just at the very beginning, in the end it could be huge. What I suggesting is for Ralph B to shoot some test at base ISO. So that we can truly see the potential of the hdmi. The cleanest signal to see and test, noise dynamic range etc. The general rule with photographic camera is the higher you go in terms of iso, the more compromise you have to do because of noise. Lets at least start at the lowest ISO.
 
Wow this is very exciting by way of what you guys are saying as I am waiting on purchasing a GH2 as soon as they are available. Can someone post a video clip with the HDMI? How hard is it to get these scripts and such to work, do you have to be a computer scientist?
 
and by the way I am seeing hwat everyone is talking about in regards to the fine particles, seeing more detail whereas they are smeared in the acvhd version, but I am not seeing any greater dynamic range however. Where can I look to see an example of that?
 
Ralph can you post some footage samples. Stills are nice but if we can see some clips it would be nice Thanks for all your great efforts
 
Just been playing with the files just to show my point. I hope that Ralph B won't mind and if it is not ok I will edit this post. My point is about dynamic range and flexibility to grade the image. Note that I am a graphic designer and photographer by profession so I have done all this in Photoshop and looking at demos of grading software it is about the same principals.

roofhdmi 1.jpg
roofhdmi 5.jpgroofhdmi 2.jpgroofhdmi 6.jpgroofhdmi 8.jpgroofhdmi 9-5.jpgroofhdmi 7.jpgroofhdmi 9.jpg

I hope it is not too big. The first one is what I call a base file. I have just corrected the file buy lifting the shadows and I just used a little noise reduction (mainly for chroma and not luminance) to preserve detail. Then I colour corrected them (graded) to see how it holds. As you can see, the main challenge is the man face. You have to choose a good balance between noise/detail and that his face is not too dark. Perhaps this shot would have been better noise/detail wise if it was shot at a lower ISO. It would have given more flexibility to lift the shadows etc.

I hope that everyone understand that I am not in any way criticizing Ralph B for his test, in fact I am applauding him for his effort. It could prove to be another milestone in DSLR film making. Just look at my above files compared to the original Avchd file, we are in another dimension even if I am working on a compressed file. I would just like to see the lowest noise files to further test what is possible with the hdmi output.
 
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