GH1 Not as I had hoped

[Thomas Richter]

Originally Posted by M. Gene Hoffman

...
2) The codec is not ideal and will make many kinds of shots difficult or impossible to reliably capture.
...

The 1080 implementation of the codec is not ideal and will make it difficult / impossible. The 720p codec will (in 95% of cases) remedy that at the price of resolution. Also, neither the 1080 nor 720 codec implementation is acceptable by pro standards.

But, what's the alternative? The 35mm adapter grain normally leads to quite heavy pixel-level degradation for HDV codecs, and everything else below 10k $ lacks shallow DOF or manual control. In fact I would be pressed hard to name anything below Red One that offers both the DOF we want & manual control.

Having said that, I am loving to film, direct and edit but I do not earn my living from video.

PS: My FX1 - SGPro R2 combo cost me approx 4500 USD. I can't count how many German film students dropped their jaws seeing the footage. Now I can get something for a third of the price with less than a 5th of the weight and size even shooting better footage. I'd say that's more revolution than evolution (even though loads of German filmstudents will buy GH1s and the jawdropping ends).

[M. Gene Hoffman]

Originally Posted by Steve Mullen

1) 1080p24 in the few cameras tested are not running at the data rate specified by Pana. They are running at half the specified rate. I've posted how this could occur by error that could be fixed.

That is fantastic news, I reeeeally hope this is the case. I would be extremely happy.

Originally Posted by Steve Mullen

2) At 720p60, the data rate is as specified by Pana and the quality is fine. Which it should be at 17Mbps.

I agree, the 720p 60 stuff looks fine, apart from resolution.

Originally Posted by Steve Mullen

3) The target customer will want 720p60. We do not want, in the 21 Century, the level of motion judder forced on motion picture maker makers by the technology limitations of almost 200 year old technology.

I make good money delivering that antiquated, outdated look. That's what people associate with high production values. For better or for worse, it is extremely important to lots of people who are interested in this camera.

If the 60p can be turned into actual, indistinguishable 24p without cadence problems, then awesome. I have heard a lot of people talking about it but haven't seen it done yet.

-M

[Oliver Smith]

This might seem like a somewhat silly question: I have never worked with 60p, so I am unaware of how to deal with it in an editing system (Final Cut). I have only shot 50i in the past (I am in a PAL country, but will be considering a non-PAL camera for 60p and 24p simplicity)

How would you go about conforming 60p to 24p? Say I shoot two clips, both at 60p, and drop then into a 24p Final cut timeline. If I wanted one at real time, and one slow, would I simply leave the first clip at 100%, and reduce the second one to 40% speed? (which would theoretically be 60p on a 24 timeline)

Would the first clip then drop frames and become, essentially, 24p? And would the second utilise its 60p information to create a smooth slow motion?

[Steev Dinkins]

Originally Posted by Oliver Smith

How would you go about conforming 60p to 24p? Say I shoot two clips, both at 60p, and drop then into a 24p Final cut timeline. If I wanted one at real time, and one slow, would I simply leave the first clip at 100%, and reduce the second one to 40% speed? (which would theoretically be 60p on a 24 timeline)

So far, from what I've seen, if you want slow motion, you should first use Cinema Tools and conform the 60p clip (59.94fps) to 24p (23.98fps). Dropping a 60p clip into a 24p timeline and changing speed to 50% doesn't do what you'd want it to do.

Originally Posted by Oliver Smith

Would the first clip then drop frames and become, essentially, 24p?

It does drop frames, but it's not necessarily elegant. The testing I've done and seen from others is showing that you'll get the best results by using a 1/50-1/60 shutter speed. However it's not perfect. To me, 60p to 24p conversion is controversial.

I documented my testing and conclusions here:
http://www.dvinfo.net/conf/panasonic...onversion.html

-steev

[Steve Mullen]

Originally Posted by Oliver Smith

Would the first clip then drop frames and become, essentially, 24p? And would the second utilise its 60p information to create a smooth slow motion?

With a 30fps timeline, FCP knows that the ratio between the Timeline rate and the number of frames per second of the video is 1:2. So FCP simply uses every other frame. It ignores every other frame. Each non-ignored frame has the shutter-speed used for shooting 60p. Which should be 1/60th or slightly longer. (You would use the same process for 25p from 50p.)

I'm not going to re-explain how 24p comes from 60p.

[Steev Dinkins]

Originally Posted by Steve Mullen

And, if you don't understand this -- go to Panasonic and read about how Varicam records 24p.

If you're talking about how Varicam and other P2 cameras record 24p over 60p, they record with information on how to extract that out. Pure 60p does not have any of that data, and there's no actual 24p inside of the GH1's 60p.

So I still assert that it's not a simple endeavor. That is, not if you want it to look as smooth as real 24p.

[Steve Mullen]

Originally Posted by Steev Dinkins

If you're talking about how Varicam and other P2 cameras record 24p over 60p, they record with information on how to extract that out. Pure 60p does not have any of that data, and there's no actual 24p inside of the GH1's 60p.

You are correct that because the Variacam captures real 24p it needs flags to tell FCP which frames to discard. But, the way the 24 get to 60 is to use 2-3 pulldown. The first frame gets repeated once while the second frame gets repeated twice. The repeats are discarded or ignored depending on your NLE.

Although there is no actual 24p in 60p -- the NLE can impose a 2-3 structure on the 60p as I explained earlier. Now what the NLE considers "repeats" are ignored or discarded -- depending on your NLE -- leaving 2 frames for every 5. Presto -- 5 goes into 60p 12 times and 12 times 2 is 24.

In terms of editing, one has a 24fps Timeline because there are only 24 non-ignored frames in every second of the Timeline. Just as there would be were 24p be in the Timeline.

I think your concern is that the interval between frames is not a constant 1/24th second. I've already said that was true -- it only averages 1/25th second. Yes -- that creates a cadence. But, that cadence will never be seen because will be hidden in an even more complex cadence created by 2-3 pulldown! (You can't see 24fps in the video world.)

The only way 24p can be seen is by imposing a 2-3 cadence so it can be viewed on a 60Hz monitor. And, we know that as disturbing as this should be -- all movies viewed in Region 60 have always had a 2-3 cadence -- and no one claims the result doen't look like film or is unsmooth -- even though it is very unsmooth!

But the proof is that those using the GH1 have already done this -- and report it works.

PS: Of course, the simplest solution is to drop 60p into a 30p Timeline. We all know 30p strobes when presented at 60Hz just like 24fps does when presented at 48Hz. It's not the absolute fps -- it's the strobing on movement that makes people "feel" film was used.

[Adrian Frearson]

I am hoping that this workflow is going to be simplified and be more transparent with PAL/European model. If I understand correctly it should be a very simple case of taking the 50p and in for example Final Cut dropping it onto a 25p timeline. Ending with what is effectively a straight 2:1 pulldown. If you want to keep all frames for slow mo, then create these first in your app of choice like compressor ( Blender does this very easily BTW! ) and then import to the timeline. If you want a 24p master for distribution then that can be easily created from the 25p project ( if you can deal with the speed change ).

"But the proof is that those using the GH1 have already done this -- and report it works."

Exactly and I think the results look promising so far.


Adrian

[Steev Dinkins]

Originally Posted by Steve Mullen

The only way 24p can be seen is by imposing a 2-3 cadence so it can be viewed on a 60Hz monitor.

Even with the trickery and stutter phenomenon involved with displaying 24p over 60hz, the motion from 24p capture film/varicam/dvx10/hvx200/etc, looks far smoother to me than the motion you get from 60p-24p conversion with 1/60 shutter (approx). If you are after a higher shutter speed look, you may be happy with the results. But when you want it to look smoother, what do you do?

To try to get a smoother look from 60p-24p, I will be using some techniques like adding motion blur, using twixtor for conversion, or conforming the footage down to 24p (resulting in slight slow down).

I haven't done testing with 25p, so I'm curious how that would work out. 50p-24p.

All of this makes me want to scrap 24fps and just reach out loving arms to 30fps. It's the easiest thing for GH1 720p and the 5DMkII already does 30p.

[Jose A. Garcia]

Originally Posted by Steve Mullen

The target customer will want 720p60. We do not want, in the 21 Century, the level of motion judder forced on motion picture maker makers by the technology limitations of almost 200 year old technology. In no other area of media has a technology that is 2 centries old become a fetish which is held to have the magic property of creating a singular path to narrative. Why does this all sound like a religion?

It's really interesting to see how so many people agreed that the lack of 24p was one of the biggest reasons not to get a 5D because it didn't look cinematic and now that we actually have that 24p mode with shallow DOF and, according to you, Steve, better compression in the future models, we're getting more and more posts in praise of the 60p mode.

Let me ask you something: If "WE" don't want 24p in the 21st Century because it's old, then why has Canon received thousands of calls and mails asking for it in the next 5D upgrade? Why is everyone trying to extract 24p from 60p in the 720 mode of the GH1? Why is so many people buying HV20s and HV30s simply because they're a cheap way to get 24p and manual shutter? Why are movies shot at 24p in the 21st Century when 35mm cameras can get to 60p and more? Why... well I guess you get the idea.

You say there're lots of countries switching to 60p for narrative work. Good for them. As for me, when I see something shot at more than 24/25p, my brain says "this is not a movie" no matter how good it looks. Times are changing and many years from now we may have lots of feature movies shot at 60p or even more but you have to agree that, for now, 24p is still the standard for narrative work. It DOES feel different than reality and that's a good thing. Our brains still switch to "movie watching mode" when we see something shot at 24p and it'll be that way for many years... maybe because we've been doing it for more than 100 years now.

I don't want to say "if something works, then why change it" because I'm not like that and it's not true. The World evolves thanks to people trying to change things, but personally I like 24p a lot and I know there're lots of people who like it as well. We've been looking forward to having affordable 24p with manual controls and shallow DOF for so many years and now that we're so close you say that we're in the 21st Century and those are things from the past? That WE don't want it?? No thanks.

[Steve Mullen]

Originally Posted by Steev Dinkins

If you are after a higher shutter speed look, you may be happy with the results. But when you want it to look smoother, what do you do?

You set the shutter-speed to match the inter-capture interval in the Timeline which is 1/25th second: alternately 1/20th & 1/30th. So you set it at 1/40th or 1/50th second. I wouldn't use 1/60th.

[Paulo Teixeira]

I’ve seen a lot of native samples that averages around 15MBPS in both 720 60p and 1080 24p. In other words, their isn’t that much of a difference in bit rates.

[Thomas Richter]

Originally Posted by Jose A. Garcia

As for me, when I see something shot at more than 24/25p, my brain says "this is not a movie" no matter how good it looks.

Jose, not that I am trying to defend this cam (although I am 99% sure I will buy one), but for us PAL users the 720 50p is great. I already conformed a lot of the native NTSC clips from 60p to 30p (completely dropping every second frame), so for us getting 25p out of the 720 50p mode is dead-easy.

The great advantage is that you always have the option to do great slo-mo later, for "Bloom style" travel documentaries and the like.

[Steev Dinkins]

Originally Posted by Steve Mullen

You set the shutter-speed to match the inter-capture interval in the Timeline which is 1/25th second: alternately 1/20th & 1/30th. So you set it at 1/40th or 1/50th second. I wouldn't use 1/60th.

Good to know. I'd like to try it on the HVX200 for test purposes, but not needed since it's got 24p recording perfected.

However, from what I was hearing, anything below 1/60th on the GH1 in 720p mode is actually 30fps. It doubles frames within the 60p stream. If this is in fact true, I believe we'd be stuck at 1/60-1/80th.

[Steve Mullen]

Originally Posted by Jose A. Garcia

You say there're lots of countries switching to 60p for narrative work. Good for them. As for me, when I see something shot at more than 24/25p, my brain says "this is not a movie" no matter how good it looks.

1) The rest of the world has been shooting 50i and 60i for decades. When I lived in Japan in the `80's no prime-time narrative was shot on film nor was 24p used. Same all over Asia. Same in Latin America. It is absurd to claim that narrative can't be done at 50i/60i because world numbers say otherwise.

2) The key is to understand that these folks do not confuse "movies" and "narrative." You, and others, have the belief that narrative can only be done if the production looks like a movie. Others know this is false. Humans respond to good stories no matter how they are told.

3) The reason folks want a "movie" look is that movies have been, and continue to be, expensive to make. Thus, if something looks like a movie it looks like like quality. (And, commercials are the biggest offenders in wanting to look like they represent quality products.)

Bottom-line, 24fps is nothing more than a marketing tool. And, it will remain that way until a famous director shoots 2K or 4K at 60p. And, theaters use their digital projectors to present the Directors Cut at 60p. Suddenly, realism will be in. (In fact, 3D may be part of this.)

So, I agree that TODAY if you want to make something that looks like a movie it needs to be 24fps. If you want to tell stories -- then "poor motion accuracy," "eye-tracking strobing," and "motion-blur" are not needed. And, when Sony starts pushing 1080p50/1080p60 next year, I believe we'll see narratives not shot at 24fps.