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Carlos E. Martinez
Mixing cameras & video formats in MC
on Apr 5, 2013 at 10:39:30 am

I have been working on a doc project for several years, starting in 2007, that should now be released as a theater feature.

Most of it has been shot in HDV with a Sony Z1 in PAL, basically because when I started up I wasn't sure what it would become: a film or TV project. That also made me do some stupid things, like shooting in DV with 4:3 format.

That will make me convert those shots to black & white and/or process it in a way so it looks good.

But what I'm considering now is buying a Panasonic GH2, which is quite affordable and seems to be excellent when compared to Canon D5 Mk II, that had been my first choice.

Using the GH2 would allow me to raise the image quality on what I still have to shoot, through a smart use of DOF, which is practically impossible to do with the Z1.

The question is the AVCHD files, that I will have to mix with those coming from the Z1. Will that be a problem?


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Michael Phillips
Re: Mixing cameras & video formats in MC
on Apr 5, 2013 at 12:00:15 pm

It won't be a problem - but it is strongly recommended that you transcode to an Avid optimized codec like DNxHD once you AMA link to the camera originals. The codec is potential a better quality and most likely the subsampling process in the camera might be different to give you a better image.


Michael


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Carlos E. Martinez
Re: Mixing cameras & video formats in MC
on Apr 5, 2013 at 12:14:47 pm

OK. DNxHD is also the format I convert my DV files too, and I will have to do that anyway.

It was advised to me not to use Avid to convert SD to HD, so I will probably use ffmpeg, as I did on my last job. Do you think there's a better way to convert SD to HD?



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Fred Gasc
Re: Mixing cameras & video formats in MC
on Apr 5, 2013 at 1:13:42 pm

Hi Carlos,

I can comment well on the GH2 as I've been working a lot with this Cam. Better than Canon dslr? It depends very much on wich aspects and it would be enough material to debate that could fill an entire book.

My GH2 are hacked (I don't count the number of different hack flavours I've tried) and as I am in Pal land I like to film 25p.
So far, I've been mixing GH2 footage with both R3D and Alexas. IMO, the GH2 footage "tends" to be more "as" the Arri (it mixes visualy better).

But the GH2 has a very very annoying side. It particulary bands (posterize) on some situations (and much more tan the Canon) when you use the AVcHD codec. The hack slightly push further the issue but hey, those are 8bits 4.2.0 and HDMI output is not great.
The only real solution (and definitive) is to by-pass the AVcHD and shoot motion jpeg. You won't have any banding but yes more noise as fast as you jump in isos. But the footage looks more organic.

In the end, it's a camera suitable for B, for indy it's perfect, but if you really want to use for clients...mmm, maybe considering the Canon will give you less hassle and you also can hack it.

Mounting a GH2 on an octocopter is a pain in the ass (to be polite). The audio mini Jack is a joke, the list is long. Strictly, the image quality, more exactly the recorded details, is stunning. You records more details than a F3 wich is somewhere amazing.

So the GH2 is a mix bag. Amazing in some aspects, very very frustrating in others. But at this Price is it allowed to complain?

Ps: listen to Michael if you edit GH2 AVcHD footage: just transcode everything. Don't stay AMAed, the AVcHD is garbage and needs to be transcoded. Nota: the transcoding stages (I do 2, one for cutting in DNxHD36 and one to conform later to a higher flavour) do not add any data. What is recorded is what is, but yes it avoids more bleeding in further manipulations. You'll see that the GH2 footage falls apart very very easily at the mínimum color manip for ex. So it's key to transcode.In my particular case, as I roundtrip to Nuke, I use a lot jpeg2000 wich stands well. I would have liked MC could read open EXR but it cannot.
AVcHD is a codec I always transcode before any manipulations.


Fred.


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Carlos E. Martinez
Re: Mixing cameras & video formats in MC
on Apr 5, 2013 at 2:08:30 pm

Thanks, Fred. I had seen another thread concerning the GH2 and Avid, and I thought it was yours. It was Alan Howard. So there's at least three people shooting, or considering shooting, with the GH2. ;)

Yes, from I have read I would definitely have to hack the GH2 if I buy it. I want it to shoot NTSC and PAL, and standard it doesn't. The GH3 does not either, and there's no hack yet.

Even if I live in an NT country, I shot this project in PAL because it's easier to transfer to film if necessary. In fact when the Sony Z1 was released I thought it was the beginning of the end for separate TV system on cameras. Unfortunately it was not, and there's very few cameras that shoot both, as they should.

Anyway, I never said the GH2 was better than the Canon 5D: I said it was excellent when compared to it, which I think is quite an achievement for the price.

About noise when shooting motion jpeg, I don't care so much for it, as long as it "behaves". I come from 16mm times, so grain is part of my world. One thing I did like about the GH2 is that it's very much like super 16, and those s16 film lenses might probably work on it, if you can find any at good prices.

In my case the GH2 would be camera A, as I think it's capable of a better resolution than the Z1. Particularly on focus fields. The only client in my case is me, as I do not work for others anymore. But it think it does have enough resolution to be the better image on the screen, all the others relating to it. As it's a doc it wouldn't be much of a problem.

Investing on a Canon system would be considerably more expensive, and I'm not sure it's worth it.

What you said about the image is the only thing that matters to me. Audio will be that recorded on the Z1 or on a separate Tascam DR-07 recorder. So what do I look for:

1) Very good image quality, with as few distortions as possible.

2) Some depth of field on wide shots when shooting people close by.

3) Better resolution than the Z1 on a big screen, closing up as much as possible to 35mm film, even if from 10 years ago.



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Fred Gasc
Re: Mixing cameras & video formats in MC
on Apr 5, 2013 at 3:09:39 pm

You're welcome.

If it's for you, I think the GH2 is a superb A cam and for a personal indy work, I would certainly choose a GH2 before any Canon dslr.

On the 16mm lenses I can't be helpfull as I've never tried them. My set is basically with 35mm Konvas lenses, both in OCT18 and OCT19 flavour. There is a guy on e-bay that build adapters to military standartd, if my memory is correct his e-bay name is cielo.

The motion jpeg is vastly underestimated on the GH2. It really looks organic, really film look and no banding, but...it fills your cards at the speed of light and you cannot record more tan a few minutes.

The GH2 banding occurs in situations like: a Wall in perspective that has a part on shade and other lited so when there are subtle transitions, water (above and under), etc etc...
It's not always there and not always bad, but when it does show-up, it's really more pronounced than with the 5D and the only way to deal with this is applying grain in post.

In terms of image, you'll have more details than with a Sony F3 ! No concerns on this side.

But then, no Log posible etc etc...

The transcode step of the AVcHD is not because of MC. I mean that even if MC would AMAed with complete reliability, playing natively with those AVcHD files is not the way to go because there aren't robust enough. It's not an Avid problem, it's the own nature of the codec. It's good for filming on consumer cams because of its relation compression/performances, but it's not good to be manipulated in post.

Best luck.

Fred.


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Carlos E. Martinez
Re: Mixing cameras & video formats in MC
on Apr 5, 2013 at 9:40:42 pm

Once again thanks for your comments, as they put a lot of things in the right perspective.

Bad news about the short capacity for motion jpeg. How long could I record and on what maximum card size?

How does that banding look? Can you show me an example? I would have to cause it an look for instances where it does show up, so I could learn to avoid it or see how to better cure it.

Can you elaborate a bit more on what problems should I have in post with the AVCHD codec?

I do not log my videos, probably because of lack of habit, and I never worried about learning about it. My fault, probably.

My camera of choice, if I had the money, would be the Sony FS100, which I think is a much better deal than any Canon or DLSR. But it's over budget at this moment, and I would have to pay 50% customs tax to get it in to Brazil. Photo cameras do not have such a problem.

And I was (am still) considering the Blackmagic as a camera I might get through customs as a photo camera. What I like about the GH2 is that the sensor size is very similar to the BM, and its lenses might probably work fine on it.



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Fred Gasc
Re: Mixing cameras & video formats in MC
on Apr 5, 2013 at 11:42:41 pm

The motion jpeg has a 2GB limit recording at once.
Very very short.

It is not a variable bitrate (it's good) wich means that if your hack is let's say 100 MB/s it would indeed records constantly at 100 MB/s.

Some infos here: http://www.dvxuser.com/V6/showthread.php?256757-100Mbps-GH2-Low-Light-MJPEG...

The problems you would meet in post with AVcHD are related to any codec highly compressed and in 4.2.0 8bits.

The Hacks are boosting the bitrate and a Little more things but they don't do anything for the 8 bits and 4.2.0

To give a paralell with still photography: You have to think those codecs as if they were bad jpegs at 7 quality. If you want to go to photoshop and edit your pics, color correct etc...jpeg are too weak. You'd need to convert this jpeg into Tiff or PSD to be able to not degrade any further. Also, like jpegs, if you make families (creating a new jpeg from a jpeg, you loose at each new family generated. Same in video, if you make generations, it falls apart quickly).

Give a pic (footage frame) that you can see the GH2 banding of AVcHD codec and the same shot in motion jpeg free of banding. I did this testing a long time ago in my kitchen. The banding is due to the high compression of the AVcHD códec.

Nota, the banding of the AVcHD is not only in the area I marked in red but if you look carefully you'll see it everywhere. The motion JPEG frame has film grain and no banding and it's very visible here. AVcHD is a consumer codec and not suitable IMO for profesional Works. For indy? perfectly fine. If you got a good story to tell, nobody will notice anything.

Pic here: http://images.creativecow.net/256203/gh2-banding.jpg

Best luck

Fred.


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Carlos E. Martinez
Re: Mixing cameras & video formats in MC
on Apr 6, 2013 at 1:47:46 am

A video file that will apart is not something I'm looking forward to. That was the main problem with analog video, which degraded with each generation, and I thought we had eliminated that with digital video.

Is there any way to prevent degrading?

You still didn't tell me how many minutes would specific cards, the largest ones you can use on the GH2 and for the hacks, will hold in mjpeg.



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Fred Gasc
Re: Mixing cameras & video formats in MC
on Apr 6, 2013 at 10:14:14 am

- How many minutes will depend on your bitrate.

- Any compressed codec degrades, to more or less proportions.
If you want the datas intacts the solution is called RAW.

If you aren't yet familiar with digital, there are different sort of codecs. Some are good for acquisition, delivery, distribution, others are good for archiving, others are good for editing (intermediate, generaly robust), etc...
You could create a thread on that if you have doubts because it's important to understand all that very well.

I read many times people wanting to edit natively with an highly compressed codec like AVcHD and they rely on computer performance to do that, but then, they color correct with as well, they create generations as well...and in the end they complain about the resulting looks. We can't ask a 4x4 to race indy.

Maybe a Blackmagic camera could be a solution reasonably priced.

If you are on a Budget, there is unfortunatly very Little ideal options and you'll have to accept many compromises. As often, the good gear is expensive.

But in the end it should not be an obstacle; better focus on good stories, good edits etc...with the camera one can afford and forget about those image quality preocupations that we see so many times over the internet.

It's way better to produce good content with a Canon or a GH2 than to produce garbage with an Epic.


IMO, the best attitude is: "how much money do I have available to spend on a cam?", buy the best you can from there and do not worry any further, do not compare with more expensive gear. It is the best you can do, and from there creates good stuff and enjoy.

Fred.


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Carlos E. Martinez
Re: Mixing cameras & video formats in MC
on Apr 6, 2013 at 1:08:05 pm

< How many minutes will depend on your bitrate. >

OK, how I set that bitrate on the GH2? Let's say 100mB/s, like the motion jpeg in your test. How many minutes would I have on that larger card the camera + hack will allow?

<- Any compressed codec degrades, to more or less proportions.
If you want the datas intacts the solution is called RAW.>

The GH2 does allow RAW, but can it be used for video? That I know the Blackmagic does allow.



Yes, my knowledge about codecs is certainly limited, or I wouldn't be making these questions here. What I'm looking for now is some advice on what path to choose. I want a format that will not degrade in post.

Apparently there are different AVCHD versions, because the Sony FS100 also records in HD MPEG-4 AVCHD, which should be the same as the GH2, and I never heard of "degrading dangers".



I need to know my limitations to work around them. That's something I did learn in my 16mm years, as the idea was to shoot 16 to blow up to 35. But there's limitations and limitations.

Resolution should be the best possible, and that is something the GH2 seems to have plenty of. Many sources comment that and also wonder why.

I will have to color correct, that's quite likely, and maybe re-framed, so I need to know which would be the best way for that, both in codec from originals and in post. That is, can or should the original be converted to something less degradable?



Yes, it may be so. But it's still in pre-order and investment would be higher. I prefer something I can buy right away. If possible something I might intermix with the BM or the FS100, or any other, in the future.



Knowing my compromises is what I'm trying to do now.



Of course, but I get the shakes when I look at some stuff I wrongly recorded in DV, when I should have in HDV. Or HDV shootings I did trusting the Z1 "optimistic" screen, and ended up too contrasty. Now I never shoot without using my portable DVD 10" screen, as I did on many of my shootings that ended quite nicely. I will have to seriously process those "mistakes" because the content is very good.

So I would like a better, more controllable image to start with. A friend of mine says the AVCHD might be a step up from HDV, which sort of supports trying the GH2.

My "quality preoccupations" are very much related to DOF control, which I have none on the Z1. Having a subject that is in the same focus as the background is distracting.



Isn't the Epic a garbage camera by definition?



I think I already did that comparison, and I'm past that. Now I need to know what I'm getting into, so I won't blame myself on what did I do.

Sorry for the very long text.



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Fred Gasc
Re: Mixing cameras & video formats in MC
on Apr 6, 2013 at 6:12:06 pm

Carlos,
These are a lot of questions and we could fill a book.

I think, on the GH2, that you're not in the right forum because you'll have much more answers reposting your questions into the DSLR video forum of this site where there are many gh2 users.

I answer quickly to a few of them here before leaving the thread.

- The GH2 does not do Raw video. It is a still camera with video capabilities, like the Canon or any other dslr. The camera shoots stills in Raw but not in video.

- In AVCHD, the minutes recorded straight can be hours on a 32GB card, depending on your bitrate.
The camera as a counter so you see what's left available.
In motion jpeg just a few minutes straight.

- You can not change the bitrate within the menu. You establish the maximum birate once for awhile according to the hack flavour you install.

- The Epic is not a "garbage camera" but a profesional camera that shoots raw in 5K and got an impressive dynamique range: http://www.red.com/products/epic

- If you want a shallow D.O.F, the GH2 is capable of that and easier on set than the Canon 5D2 as its sensor is smaller. (the Canon is less forgiving)

- You can read this from Avid to see the different DNxHD flavours and how you can make your choices according to your needs and the sapce available on your drives: http://www.avid.com/static/resources/US/documents/dnxhd.pdf

I recommend that if you want to have a lot of informations on the GH2 from different users, your best bet is to create a thread in the DSLR forum.

Hope I could have been a Little helpful.

Best luck.

Fred.


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Carlos E. Martinez
Re: Mixing cameras & video formats in MC
on Apr 6, 2013 at 8:53:22 pm

Thanks, Fred.

I also felt this was betting too specific and not Avid related. And was already thinking of going to the DVX GH2 forum. If there's one at Cow's it's even better.

Pity motion Jpeg is not a real option, as a few minutes doesn't serve me.

Thanks again.



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