25p official topic, aka Don't cry for me Argentina

Mark_the_Harp

There has been talk in the low GOP thread about a high bitrate / low GOP setting for 1080i which I'm going to try now my computer is back in action. In terms of detail at least, none of the high-bitrate 720p footage I've seen has been as good as even the stock 24p (IMO) so I'm keen to see what you can get out of 1080i 50. For me the interest is twofold: I'm in a PAL region, and I have 2 HD camcorders to use alongside my GH2.

alcomposer

@andres

honestly- get a GH2 - by the time the GH3 is hacked into shape (taking into account that Panny will not be sending VK a SDK) you will probably we wanting to get the GH4... Vicious cycle... Nip it in the bud...

720p50 is great for news etc, and when it gets higher bit rate it will scream - remember the GH2 is doing pixel binning not frame skipping- so as far as I am aware - all the lovely data is being used!

(someone correct me if I am wrong)

rogerpilly

@Donnie88

"Why would you not get slow-mo with this?"

You could, but you'd have to duplicate frames or use a plug in like Twixtor or other forms of artifacts. While there is an opportunity with DSLR to shoot natively at 60 fps, then conform it with Cinema Tools at 24 or 25. When you play it back it is natively slowed down by 2.5 (at 24, slightly less at 25). In this case you get beautiful slomo, as good as when originated on film by overcranking the camera.

andres

sad, sad, sad.
I think I will pass on the gh2 (happy with my gh1, it just works).
perhaps gh3 will bring 1080 50p and global shutter.

Butt

@PixCanFly
my settings for 720/50p

Donnie88

@rogerpilly That would be even better if you get less compression with the PTool 720/25p. Why would you not get slow-mo with this?

@PixCanFly If the PTool 720/25p is good, then there may not be a need to do the 720/50>720/25p>1080/25p method.

PixCanFly

With a higher bitrate hack, I think it's a viable option to shoot 720/50p and edit on a 25fps time. Upscale 720 to 1080 is not a problem. Previously, the unhack GH2 720/50p (17mbps) is just too low.

Btw, what's the most stable and gorgeous looking 720/50p setting for hacked GH2 at the moment?

rogerpilly

Actually, why not shooting 720/25p, as it's now possible with PTool 3.61d? Unless you need to slomo, my understanding is that you get less compression vs. shooting 50p. Anyone can confirm?
And also, another method would be to shoot at 1080/24p, conform to 25, edit and then slow it down to 96% using Twixtor, as stated in one of their tutorials. I have done a short test (rendering takes forever on my 4 and a half year old Macbook Pro) but I didn't notice any artifact. Any thoughts?

By the way, thank you very much Vitally, wonderful work! Very much appreciated!

Donnie88

Fantastic, that's all sorted for me. I'll export the 720/25p in 1080/25p then.

Sounds like problem solved until they bring out native 1080/25p.

bdegazio

@Donnie88 - Just create a 25fps timeline and drop your 50 fps footage on it. FCPX automatically plays it back at 25 fps.

Donnie88

In Final Cut Pro, you know how to do it?

If this is possible, then I may go for that method; Shoot 720/50p > Frame skip so it's 25p > Export 1080/25p.

Elenion

It depends of the software, in premiere you have to select "interpret footage" and the project has to be in 25p. It makes all by himself.

Donnie88

And 720/25p exported as 1080/25p shouldn't be too different from native 1080/25p, right?

If so, this does seem like a temporary solution.

How would I skip frames? Surely not manually?

Elenion

If you want 720/25p just use 720p50 and then frame skipping

Donnie88

It wouldn't be a good solution. As Elenion said, the 1080/50i is interlaced (it's not 1080p/50) - so you will get half vertical resolution is every other frame is dropped. Big no-no, that option is out of question.

It does seem 720/25p might be possible, but not sure.

Elenion

@Mark_the_harp
I think mpgxsvcd was referring to the fact that if the shutter goes below the fps the camera record just the frame it needs. This means that if you record 50p at 1/25 the camera record just 25fps (that you have to interpret during editing), but the fact is that gh2 doesn't have (yet) 1080p50, it has only interlaced ones, then you can get 1080i25.
I don't think that it could be a good solution.

Donnie88

Any further testing of 1080/25p to see if there is hope?

Also there seems to be 720/25p, has this been tested at all?

Mark_the_Harp

@mpgxsvcd "You can also get 1080p @ 25 FPS from the GH2 by dropping the shutter speed below 1/50th."

Could you just explain that? I think I get what you mean but I'm not sure! And of course it's not going to have the data rate of the stock 24p mode unless you also tweak the data rate settings on a hacked camera.

Elenion

Well, even better if we could record at 1080p50...

fatpig

to me it looks like it could be possible to use 50p sensor mode and encode it to 25p 1080... time will tell if VK can do this :)

mpgxsvcd

@stolpis100

I would say the 14-140mm is a great starting point with the GH2. Its small aperture is not useful for the GH1. However, the GH2 has a 1-stop advantage over the other m4/3s cameras so the 14-140mm is usable.

After that I would get the upcoming 25mm F1.4 over the 20mm for video. If you manually focus or use AFS the 20mm is fine for video. However, the 25mm looks like it will be an ideal video lens.

After those I would say the 45mm F1.8 or perhaps the 45mm F2.8 with IS would be good choices. However, I really like my old MF lenses in that focal range.

madact

All of which is still 1080p in the same way as that iPhone 3 app that 'upgraded' the 2MP camera to a '7MP camera'... man that was hilarious. No argument that the camera is awesome, I agree that good 720p is better than crappy 1080p, and I personally will be fine for my needs with the modes available (now that we can get 24, 30, 50 and 60 together). But 1080p PAL would be even awesomer :o)

@stolpis: lots of threads in the gear section... I'm going for a 14-45 for starters myself and maybe a fast prime like the panny-lieca f1.4 or the nocton down the track, but I have some old Pentax K-mount glass and a Volna-3 on a tilter, that I plan to re-use. Gotta love micro 4/3, it'll take (almost) anything.

stolpis100

Right that's it, i'm getting one. The only ones I've seen physically available in shops have the 14-42mm lens. Am i right in thinking the 14-140mm is the basic starting point lens I should go for? This is my first real step into camera work, I've always hired DOPs for previous projects.

Mimirsan

GH2s hacked 720p 50p mode is very good indeedy...almost 1080p looking in terms of other camera comparisons.

mpgxsvcd

You can easily get 25p with a stock GH2. Just shoot 1080i and deinterlace it. So many people complain that 720p doesn’t have nearly as much resolution as 1080i. You can also get 1080p @ 25 FPS from the GH2 by dropping the shutter speed below 1/50th.

Now in reality the 1080i mode has terrible vertical resolution so this isn’t really a viable solution. Shooting 720p @ 50 FPS with the upcoming hack will produce perfectly acceptable 720p @ 25 FPS. You can always upscale it to 1080p @ 25 FPS if it must be 1080p.

I wish I had a GH1 to test against the GH2’s 720p mode. The GH2 ‘s 720p is so much better than the non GH series cameras.

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