The files are 24p mts, bitrate is variable/typically 35 to 60mbps. Clip length averages from 2 to 5 minutes.

I used a program called 5DtoRGB, transcoded to DNxHD/the default settings, which were:

Decoding Matrix: ITU-R BT 709
Luminance Range: Broadcast Range
Post-Processing: None

OK, that's not much information.
Please use MediaInfo (download from Sourceforge) to post the complete details from both files.

I know nothing about the transcoder you used; DNxHD is routinely used from within Vegas for both encoding and decoding. Download and install the Avid 2.3.8 LE codecs for Windows.

I did download and install Avid LE 2.3.8, but it's not appearing in any of Vegas' drop-down menus, including avi. It's installed because it appears in the drop-down menu in 5DtoRGB, the program used to convert to DNxHD.

Here is the MediaInfo. (I see the bitrate on the converted file states 176 Mbps. Why did it raise the bitrate from 37.9mbps?)

Original mts file:
______________

Format : BDAV
Format/Info : Blu-ray Video
File size : 453 MiB
Duration : 1mn 40s
Overall bit rate mode : Variable
Overall bit rate : 37.9 Mbps
Maximum Overall bit rate : 99.4 Mbps

Video
ID : 4113 (0x1011)
Menu ID : 1 (0x1)
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.0
Format settings, CABAC : No
Format settings, ReFrames : 2 frames
Codec ID : 27
Duration : 1mn 40s
Bit rate mode : Variable
Bit rate : 36.2 Mbps
Maximum bit rate : 128 Mbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate : 23.976 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.728
Stream size : 432 MiB (95%)

Audio
ID : 4352 (0x1100)
Menu ID : 1 (0x1)
Format : AC-3
Format/Info : Audio Coding 3
Mode extension : CM (complete main)
Codec ID : 129
Duration : 1mn 40s
Bit rate mode : Constant
Bit rate : 192 Kbps
Channel(s) : 2 channels
Channel positions : Front: L R
Sampling rate : 48.0 KHz
Bit depth : 16 bits
Compression mode : Lossy
Stream size : 2.29 MiB (1%)

Text
ID : 4608 (0x1200)
Menu ID : 1 (0x1)
Format : PGS
Codec ID : 144
Duration : 1mn 40s


Converted to DNxHD in 5DtoRGB (get error message when trying to import into Vegas):
______________________
Format : AVI
Format/Info : Audio Video Interleave
Format profile : OpenDML
File size : 5.40 GiB
Duration : 4mn 21s
Overall bit rate : 178 Mbps
Writing application : Lavf53.24.0

Video
ID : 0
Format : AVdn
Codec ID : AVdn
Duration : 4mn 21s
Bit rate : 176 Mbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate : 23.976 fps
Bits/(Pixel*Frame) : 3.540
Stream size : 5.35 GiB (99%)

Audio
ID : 1
Format : PCM
Format settings, Endianness : Little
Format settings, Sign : Signed
Codec ID : 1
Duration : 4mn 21s
Bit rate mode : Constant
Bit rate : 1 536 Kbps
Channel(s) : 2 channels
Sampling rate : 48.0 KHz
Bit depth : 16 bits
Stream size : 47.8 MiB (1%)
Interleave, duration : 32 ms (0.77 video frame)
Interleave, preload duration : 96 ms

Avid DNxHD is a Quicktime MOV codec. It is not AVI.
It does not appear in the templates dropdowns because it is not a Vegas template!
It is a Custom Video Render option under Quicktime. Then you can access all the DNxHD templates.
You can even make your own Vegas template if you wish ;?)

You are currently rendering your DNxHD intermediate at 178 Mbps, which is higher (and larger) than necessary. Experiment. An best of luck.

If you would upload a camera sample of your GH2 footage somewhere, others here could look at it and offer some guidance. ("Somewhere" is not Youtube.) I know of no one else who has mentioned this particular behavior with GH2 footage in Vegas.

There are other GH2 users on another forum who have the same issue in Adobe Premeire.

I didn't realize DNxHD was mov only. There was an option for AVI also. That program has raised the bitrate, there's no option to change bitrate settings.

Is the workflow to export from Vegas with DNxHD and then re-import back in?

That is what I would suggest.
I am still interested in seeing your camera footage, because if there is an issue in Vegas with GH2 footage, this is the first I've heard of it.
It's also important that you post your Vegas and Quicktime versions.

Thanks.
Here's an example (I had to mask out the person who appears in the video):


Look on the right side for the rain. Some clips have more than this.

"If you would upload a camera sample of your GH2 footage somewhere, others here could look at it and offer some guidance.

If you're unable to provide an actual camera clip for download, I won't be able to help further. Thought I made that clear. Best of luck.

Actually, YouTube is somewhere.

Youtube reprocesses video, making it impossible to attempt to duplicate your observations. But sorry to have inconvenienced you. Maybe someone else can help.

It's only seen in renders, not in the original mts.

A general idea can be had from the YouTube video.

That "rain" certainly isn't that easy to see, at least not on the office PC monitor.
My guess is that it's coming from the camera. Passing the footage through an additional encoding process is simply providing enough smoothing to blur it out.

I'm not familiar with what the GH2 hack does but if it's enabling higher bit rate recording then there's the problemo. Higher bit rates with less loss sound like a great idea and generally they are. The exception is with some cameras the stock encoder also providers noise and artifact reduction.

Another classic example of this type of issue is with the Convergent Design NanoFlash and the EX1/3 cameras. At 50Mbps 4:2:2 Long GOP all is good. At 100Mbps, only the I frames fully encode the noise so you get this jittery noise pattern in the midtones. Bump the bitrate up / use I frame only and all is OK.

As Musicvid rightly says this is beyond impossible to even really guess at well without camera original fooatge. What's on YT has gone through one if not two additional encoding passes and all of them lossy and all of them very likely to affect what we're seeing.


Bob.

I understand your point regarding higher bitrates except, at least in this case, this is an inherent issue with the GH2 as I had this kind of digital noise with the stock firmware, before using the hack.

At a site that has a number of different GH2 hacks, one thing the developer of this hack advertised was addressing these kind of noise issues. And it works, for the most part, except for these conditions where there is no fill lighting in the background. The GH2 also has a known "ISO bug" which requires the operator to go to a higher ISO, then back down to the target ISO. (Hack or no hack.) After powering the camera back on, I may have forgotten to do that for some of the takes, which may have something to do with this anomaly.

There are other hacks that do not display this digital rain once rendered from the NLE. The catch is it requires a Sandisk 95MB/s SDXC 64GB card, goes for about $130 each. At least two would be needed as the high bitrate eats up the available data.

I was trying to get this present hack to work in that I already have Sandisk cards with lower specs suited for this particular hack. I may just end up buying the better cards with the better hack/which would also require more PC storage space.

I tried the DNxHD renders/re-imports using Vegas, with a few different settings, then replaced the mts file in the project. The rain was still there.

Below is a link of the same file from that YouTube video. I had to mask out the person, the black area, because I don't have permission to show their image. The rain only shows up in the renders. Providing the original mts file won't show the rain and I also won't be able to mask out the person without a render. Look on the right side of the image for the rain (30MB):
http://www.adrive.com/public/zhscUC/digital%20rain%20example%20-%20subkect%20masked%20out.mp4

This is a better example (53MB):
http://www.adrive.com/public/sVFczh/digital%20rain%20example2.mp4

All I'm seeing is simple sensor noise with compression artifacts.
The best fix is to not use a higher ISO than the camera's native ISO. For the GH2 I'd hazard a guess at that being 400. You could even try a lower ISO of say 200 or 100. From whatever ISO you find works best you have to light for it.

You'll also find using only daylight light sources will help.
The blue photosites are the least sensitive and hence the noisiest. With Daylight lights the white balance reduces the gain of the blue channel and that reduces the noise.

Recording with a higher bitrate codec would capture the noise without added artifacts and make it more amenable to some form of noise reduction in post and/or make it easier for a downstream codec to deal with. Byfar the best fix is to avoid the noise in the first place as I suggested above.

Bob.

I'm a GH2 hack user, but don't transcode my footage to DNxHD. Are you using this format for any particular reason? -Export EDL and such? I always through all clips on a timeline and render to .mxf HD422 1920x1080-24p 50Mdps. Everything works great for me. Doesn't really solve your problem, but just sharing what I do. Let's me stay all in Vegas. - For what it is worth.

Someone on another forum provided the solution. When installing Avid DNxHD on a machine, you have to have Quicktime (with ProRes) installed first, then install DNxHD on top of it. (I never had a use for Quicktime and just recently installed it after installing Avid.)

I then removed Avid, then installed in the correct order. Now Vegas will accept the DNxHD files. When replacing the mts files with the DNxHD versions, all the digital rain is gone. (I replaced the files because the project was already completed, but for a general workflow the mts files need to be converted first to DNxHD, then proceed with editing the project.)

As mentioned, I used a program called 5DtoRGB to convert to DNxHD. I still need to find a batch script for it. I also learned that if you render out DNxHD from Vegas, then re-import, it's not addressing the problem as the rain gets embedded within Vegas.

I think you still have a point regarding the use of day lights. I already have reflector lamps and see there are specialized bulbs for that. I think it will help the issues you stated.

Regarding ISO, I actually once shot live footage in a dark club and stage lights with the ISO on the GH2 set at 6400. There was noise, but none of that animated rain, it was just regular noise similar to a still. I was able to use a plug-in to clean up the noise without issue.

The rain issue has to do with the codec on the hack. Have you tried a different patch??

I had a similar issue in which major blocky patterns appeared during 720p/60fps shots during a music video. Drove me nuts, had to reshoot it. These weird pulsating patterns. The same hack looked GORGEOUS on 1080p/24, but on 720p/60 it was destructive.

The digital rain is something I saw on earlier hacks, but no on the one I am currently using. I am not at my main workstation where I keep all my patches, otherwise I'd recommend several. Sanity v4 had that issue, and it was fixed with the latest version.

Nick Driftwood's stuff is always well-explained and I have NOT had that issue with his patches, when used according to the description. (Some work great at 1080p/24 and refuse to work at any other resolution/frame-rate.)

What patch are you using?