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flinty

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To M Gilden

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Originally Posted by flinty
Of course that was not tripod footage,i have been saying i get good tripod footage read the pages,i use a good velbon but there are times when i dont want to carry it around,sometimes miles,and even brace footage is not to a good standard but its not my filming but my GH2 has to be rock steady using zoom lenses. Sorry wish i had not mentioned this problem on this thread.



You did mention it Flinty, but I think many users here glossed over it because it didn't make sense to them. Footage that exhibits severe moire and aliasing would still appear with or without a tripod. But you are correct in that it doesn't belong in this thread- we'd be happy to discuss the merits or faults of your observations in another thread if you'd like.

Regarding my problem,i can state without any doubt i do not get moire and ailising if the camera is fixed on a tripod,only when the camera lens has any movement,it is wors with zoom lenses than pankake lenses.
 
flinty said:
i can state without any doubt i do not get moire and ailising if the camera is fixed on a tripod,only when the camera lens has any movement
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And I can state with a pretty high degree of confidence that your conclusion is based on faulty data. Those artifacts are a function of the scene, not whether or not the camera is on a tripod.
 
Moire and aliasing are more obvious when the camera has a small amount of movement, but the moire and aliasing are still there when sitting static on a tripod. ( just not as obvious to spot )
 
Exactly. Flinty, if you'd like, post clips of the same scene taken with or without a tripod. Maybe we're not talking about the same thing?
 
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Flinty, when I downloaded your footage, I noticed the pattern on the roof looked similar to my recent complaint of "digital rain". See this thread:
http://www.dvxuser.com/V6/showthread.php?302454-How-to-avoid-quot-digtial-rain-quot

As recommended in my case, I ran the footage through a program called 5DtoRGB and trancoded to the DNxHD codec/mov extension. After transcoding and viewing your files, that heavy animated noise activity on the roof/patterns were gone. I still see M&A on the fence when you move the camera but FWIU a fence pattern will be hard to avoid that.

I rendered the first and third files to mp4 in Sony Vegas (146MB):
http://www.adrive.com/public/QJyUqK/0090-0092 rendered to mp4 in Sony Vegas 25P.mp4

Transcoded to DNxHD (594MB) only using 5DtoRGB/Vegas not involved:
http://www.adrive.com/public/d7XVue/00090 DNxHD.mov

If you want to transcode them yourself, install 5DtoRGB and the DNxHD codec.

DNxHD codec:
http://www.avid.com/US/industries/workflow/DNxHD-Codec

5DtoRGB:
http://rarevision.com/5dtorgb/

I used the free Windows 32-bit version (even though I have a 64 bit machine this version is more DNxHD-specific)...and there is also a Mac version there.

My settings:

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I don't know if that issue on the roof is technically M&A, but the transcoding worked, at least for that. As stated in the thread I linked, someone claimed there might be defective camera batches. I noticed when installing the Sanity 5.1 hack, which has fairly low bit rates for a hack, there was no need to transcode the footage. Maybe you might want to consider installing that hack.

Sanity 5.1.zip
 
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UPDATE: I don't mean to cause confusion here..but just noticed that when I render out the mts files in Vegas, while treating it as progressive in the project properties and render, the patterns on the roof are similarly gone (without transcoding).

But the transcoding (without Vegas) also got rid of the patterns. Is 5DtoRGB also doing something with the interlacing?

Small file/32MB/put on loop in media player:
http://www.adrive.com/public/WqeV4X/MTS then DNxHD.mp4
 
Looking at Flinty's footage in my Sony Vegas Pro editor with the timeline set to progressive mode, I'm not seeing much moire at all but I am seeing aliasing on fine details like the metal fence or the distant roof shingles. Visually I'm not seeing any real problems with this footage, other than the minor aliasing which would be the same if you shot this with the GH2 camera.
 
Using CS5.5 I have never transcoded Gh2 footage. Everything looks/cuts and works fine and fast. Renders and exports seem to be made quickly and cleanly. I may be missing something, but can someone explain why there is a need to transcode. I know FCP needs Pro res files, but do any other PPro users transcode ?
 
Prior to CS5.5 there were some flaws in how Premiere was handling the Panasonic AVCHD files, but this has been resolved as of CS5.5 so there is no longer any need to transcode if you are working exclusively within Adobe CS. However, if you project has any chance of being worked on in another NLE platform then you risk problems. If you suspect a project might be moved to another system then transcoding with 5DtoRGB will help ensure consistency across platforms.
 
I looked at the media info and the original mts file is "interlaced/top field first".

Just shoot in progressive.
 
malibudutchie said:
Using CS5.5 I have never transcoded Gh2 footage. Everything looks/cuts and works fine and fast. Renders and exports seem to be made quickly and cleanly. I may be missing something, but can someone explain why there is a need to transcode. I know FCP needs Pro res files, but do any other PPro users transcode ?
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DPStewart said:
Prior to CS5.5 there were some flaws in how Premiere was handling the Panasonic AVCHD files, but this has been resolved as of CS5.5 so there is no longer any need to transcode if you are working exclusively within Adobe CS. However, if you project has any chance of being worked on in another NLE platform then you risk problems. If you suspect a project might be moved to another system then transcoding with 5DtoRGB will help ensure consistency across platforms.
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If you are referring to why 5DtoRGB seemed to make a difference, there are quite a few threads on this topic already. I don't want to hijack the thread, but in a nutshell the general theory has to do with how color space is converted from yCbCr to the RGB color space most NLEs require. The way I understand it, the footage from the camera is yCbCr and 4:2:0. When you are working in an editor like Premiere, it is working in full-spectrum 32-bit RGB, so it has to translate the color space on the fly. Usually this is fine, however some users have reported a noticeable aliasing artifact along edges of certain colors. I haven't been able to confirm this, but I've been told that Premiere uses a nearest-neighbor style algorithm to convert to RGB, whereas 5DtoRGB uses the much more complex and computationally expensive lanczos one. The lanczos method isn't good for real-time editing, however can help smooth those lines out if they ever occur.

Personally, the GH2 has been so moire and aliasing free that I hardly ever feel the need to transcode anything. I have used it a few times when working with a chroma key, but in the end I'm not entirely sure it made a noticeable difference. Here however, it appears to have done something, but I'm wondering if it has more to do with interlaced footage than it does color space conversion or sensor sampling problems. I did notice that VLC reported the stream is 50fps, and at 1080 resolution, the gh2 only does 1080 50i or 25p.
 
If anyone thinks the non tripod is as good as tripod mm what can i say,GKHN you can see the problem at least,TheDingo if you cant its pointless because it is there and recording 24P has the same results,if any programn like GKHNs helps its worth considering but i shall use my GH2 for stills and tripod video only i expect.Thanks for the replys
 
Flinty, Are you able to drop the avchd file from the gh2 directly to your editors timeline without adding any steps in between, Also,, why are you shooting interlaced video?
 
flinty said:
TheDingo if you cant its pointless because it is there and recording 24P has the same results
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Working from the MTS files I am seeing almost no moire, but there is a little bit of aliasing in very fine details. The aliasing is more pronounced with camera movement, which is to be expected.

Your footage is 50i interlaced, which needs to be removed in order to realize the full image quality. Perhaps you can post some full resolution frame grabs of what you are seeing, just to confirm we are on the same page.
 
maranfilms said:
Flinty, Are you able to drop the avchd file from the gh2 directly to your editors timeline without adding any steps in between, Also,, why are you shooting interlaced video?
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My GH2 will film 720P which is lower resolution than 50i also 50i /HBR 25P in a wrapper and 24p,you ask why i use interlaced well i use HBR mostly,24P has as much M & A as HBR and an overall look i dislike.As for the first part of the question i dont know but is there a relavence to having shown the problem with my raw files.
 
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