GH2 No 25p possible in GH2 hack

So is mpgxsvcd's suggestion of shooting in 720/50p then exporting at 25p more logical than shooting in 24p and converting that to 25p?
 
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Mj882 said:
So is mpgxsvcd's suggestion of shooting in 720/50p then exporting at 25p more logical than shooting in 24p and converting that to 25p?
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If you can refrain from the extra image quality 24p will give you it should be an easier workflow, especially if you do musicvideo (as I understood) and have to lip-sync.
 
Mj882 said:
So is mpgxsvcd's suggestion of shooting in 720/50p then exporting at 25p more logical than shooting in 24p and converting that to 25p?
Click to expand...

One method(24p to 25p) distorts the video(Slightly but it does require some adjustments). The other one just upscales the video to 1080p and retains all of the recorded resolution.

It is up to you to decide whether the image quality of the second picture below is close enough to the image quality of the last picture below.


http://twills.fatcow.com/Share/Video Resolution/GH200001 AVC 720p 0 IR.png

GH200001 AVC 720p 0 IR.png


http://twills.fatcow.com/Share/Video Resolution/GH200001 AVC 720p 0 IR_resize.png

GH200001 AVC 720p 0 IR_resize.png


http://twills.fatcow.com/Share/Video Resolution/GH200001 AVC 1080p 0 IR.png

GH200001 AVC 1080p 0 IR.png
 
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Cheers for the examples mpgxvcd. I can't really see a difference in quality to be honest, I'd have to see them in motion.

So it would come down to which workflow is most efficient.

Yeah the new PTool is out...no 25p :(
 
mpgxsvcd said:
One method(24p to 25p) distorts the video(Slightly but it does require some adjustments). The other one just upscales the video to 1080p and retains all of the recorded resolution.
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Distorts the video? Yes, if you double some of the frames and/or blend some of the frames. In this case sound remains unchanged, but picture is not perfect.

However, if you just increase the speed, the resulted video remains exactly the same. Of course, you'll have to shorten the sound by resampling it at 4% lower frequency and then modifying sampling frequency to the original one without resampling (of course, there are tools, even freeware, which can do it automatically). As already said on this thread, you will always decrease sound quality. One solution is to always use external recorder with 96kHz/24 bits settings before doing resampling. Sound quality can remain very high, but pitch is higher.

So, almost perfect transition from 24p to 25p can be obtained, but there are other obstacles, like using multi-camera setup with different rates and artificial lighting problems (flicker) at some shutter speeds, etc. These problems are real. We cannot avoid them.
 
Mj882 said:
I can't really see a difference in quality to be honest, I'd have to see them in motion.
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There is practically no difference between 720p and upsampled 720p, since it is UPSAMPLING, not downsampling. Resolution is mostly retained. However, when comparing upsampled picture to 1920p24 I can see the difference.
 
Not to dissuade you from exploring this question of re-time-mapping a 24P to a 25P project...but I'll say it again, I don't know why you'd bother. Shoot at 24P. Finish at 24P. Burn and exhibit at 24P. That's it. These days, I can't see why that's a problem, even in PAL land. That way, you never have to re-time the 24P footage: you don't have the hassle and you don't get any artifacts introduced into the footage either.
 
So as the sensor has a 50 fps mode is 1080-50P at a decent bit rate (40+ mb/s) a possibility....that would be fine for broadcast use would it not?

You could just drop every second frame for editing on a 25P timeline plus you have the option of 50% slow motion playback also if you needed it.
 
sean90291 said:
Not to dissuade you from exploring this question of re-time-mapping a 24P to a 25P project...but I'll say it again, I don't know why you'd bother. Shoot at 24P. Finish at 24P. Burn and exhibit at 24P. That's it. These days, I can't see why that's a problem, even in PAL land. That way, you never have to re-time the 24P footage: you don't have the hassle and you don't get any artifacts introduced into the footage either.
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I'll be needing 25p to fit into my showreel. The rest of my work are 25p, and if I begin to shoot stuff in 24p - adding it to my 25p is going to be a pain, no?

Majority of the film festivals down here want PAL dvd's and not NTSC. Would that still be a problem if I finished at 24p?
 
sean90291 said:
I don't know why you'd bother.
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Because 24p does not suit artificial lights in PAL countries. Have you ever herd of flickering problem..?
Half of the world are PAL countries, but GH2 PAL version has no PAL frame rate - that is the case!
 
lpowell said:
The best results I've obtained are with the 100Mbps Max Latitude Patch
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Hi - first - thanks for the time & effort you put into this patch.

I installed it in my (previously hackable) GH1 and was initially very pleased with the results.

Testing indoors, there was a noticeable improvement over my previous 'standard' 32Mbit settings, even though the average bit rate was only around 25Mbit.

Testing hand-held outdoors, the bit rate averaged about 35Mbit, with no lock-up or other probs. I was feeling very pleased with myself - until I tried a static foliage test.

The camera reported the usual memory card speed error after about 2 minutes - I tried again, this time lowering the exposure values.

Still no joy - in fact, the camera now began to report the 'unable to write' error after the first few seconds. I don't know what the bit rates were because, obviously, the files were not saved.

OK, I assumed I required something better than my Transcend class 10 - but, just to check again, I installed the 'standard' 50Mbit Ptool settings (but left 25p unchecked)

Using the same fol;age test, the camera ran for 15 minutes without a hitch, until I turned it off.

The average bit rate from this test was 40Mbit - so, obviously, the card is easily capable of that sustained speed.

So, presumably, this means that a faster card isn't necessarily going to solve my 'Max Latitude' problem? I'm loathe to spend the best part of $100 (equivalent) on something that might not be necessary.

It seems clear that the problems occur when 25p is invoked. I realise that I don't know the bit rate from the static 'Max Latitude' test - but I doubt if they were significantly higher than the hand-held test, or the static 'non 25p' test.

I'd really like to persevere with this patch because the dynamic range was certainly improved - but, frankly, I don't know where to go from here.


Cheers
 
For 3/5 of the world 25p is VITAL. For Panasonic to have dropped this from so-called European versions of the GH2 was just crazy. It makes absolutely no sense to buy a crippled Euro version if you are only going to be shooting in 24p. Maybe this is why there are so many Euro GH2s knocking about and very few NTSC cams available to buy?

Although 24p is a nice addition, the two main aquisition progressive frame rates in the world today are 25p and 29.976p (and their interlaced equivalents of 50i and 59.952i) without these basic framerates, the camera is little more than a consumer SLR without the IQ of Nikon/Canon.

I am happy using my 25p GH13 - wouldn't consider a non-25p GH2 at ANY price! Maybe the GH3 will re-instate the lost frame rate, or maybe its time to look elsewhere.
 
I believe that 1080p25 is possible. It's just that people don't want to experiment with the PTool but d$$k around by meaningless stuff like shortening the GOP and raising the bitrate (it will deliver high bitrate but with codec gets horribly inefficient).

AVCHD Movie Mode -> AVCHD FPS -> 1080p Progressive enables the 1080p25. Only problem is that encoder is still receiving interlaced picture. If we could fool sensor to send progressive frames to encoder, it would work.

That's where "Patches for testers -> AVCHD research -> Encoder Setting x" comes into play.
For example, we know that "Encode Setting 1 720p = 3 enables B-frames for 720p. (which IMHO looks better that short-GOP IpppIppp stream with very high bitrate and horrendeous codec efficiency).


So if we could concentrate on exploring "Patches for testers -> AVCHD research -> Encoder Setting x 1080x" instead of eeking out the last bit from lousy short-GOP no B-frame stream I believe we can get 1080p25 to work.


Frankly, a well-working 1080p25 with B-frames and reasonable bitrate (heck, 24Mbit will do) would be enough for me. It's essentially what AF100 outputs.
 
25p has always been unstable on the GH13 when using wide angle lenses...even at so-called reliable bit-rates. I've always been happy using 1080 50i @ 35-50mbps. It's labeled "50i" but it's actually 50i progressive segmented...so Edius simply handles it as if it's 25p (Pal users don't have funky pulldown issues)...absolutely no extra work required.

My brand new GH2 just had the hack today and is now shooting 30-40mbps 50i PsF. Actually best of both worlds...50i ready for Blu-ray or 25p ready for Pal broadcast. The bottom line is that the image IS being captured in 25p...so what's with all the grief? It really was only an issue with the factory castrated Pal GH2 shooting 50i @ some stupidly low bit-rate.

By the way...the image quality out of the hacked Gh2 is stunning...
 
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Grunf - Please post all of that to Vitaly's website, people need to recognise the importance of us shooting 25p than the GOP/bit rate stuff.

Skeptikal - So subsequent to hacking my imminent GH2, if I shoot in 50i, it will end up being 25p in the timeline? Elaborate please, this sounds promising. Surely 50i doesn't look as filmic and organic as 25p?
 
Skeptikal said:
The bottom line is that the image IS being captured in 25p
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No. GH2 captures true 50i signal. It's NOT 25p wrapped into 50i container as GH1. Thus, you get either half of vertical resolution or combing when you try to make 25p of it.

(If GH2 really captured 25p in 50i wrapper we wouldn't have this discussion. Higher bitrate would be all we needed...)
 
I have both gh1/gh2 Im a big user of 25p but there are 3 solutions

1)shoot 24p and interpret into 25p (sound difference is small) I use pre pro and you can batch interpret with a click of a button

2)Use 50i mode...deinterlace...or use 720p 50p (the 720p @high bitrate is very good better than other cams at 1080p) and upscale..and enoy the benefit of smooth slomo if needed

3)Keep or buy a GH1 and use the native patch (albeit unstable) or say f*** you panasonic and go canon or nikon (and enoy the lowres and alaising..oh and lack of EVF and manual controls for nikon)

All in all...I use the 24p to 25p route...and the image quality is superb.

VK Has clearly stated there is no 25p in sensor modes...this to me sounds like something more substantial than just fixing it in ptools.

if nikon or sony release a camera with manual controls with ALL standard framerates...im gone. ive very nearly had it with m4/3 and their piss poor current lineup.
 
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