50Mbps AVCHD Fast Action 3-Frame GOP Patch

lpowell very strong work thanks so much for these great results!

This may not be possible but would it be possible to combine your 40Mbps reliable settings for 1080 AVCHD and MPEG and with the settings for the 720p30 patch.

Or is the best way to do it is to upload and switch out firmware depending on your needs?

Thanks in advance!
 
i take mostly candid video, and this new 720p/30p for more action seems to fit the bill.

is there any subtle difference between 30th & 60th and 50th & 100th shutters?
 
lpowell:
is it possible to have avchd 1080_24p, 720_60p and 720_30p modes at the same time?
if i'm shooting 24p stuff, i'd like to be able to capture 60p for slowmo.
and if i'm shooting 30p stuff, i'd prefer not to have to load different firmware.
 
quick question to anyone shooting with a setting that doesn't allow you to playback and review in-camera:

how do you manage this? do you only use these settings when you're close to a laptop or for things you can shoot multiple takes easily?

how do you deal with not being able to review your shot? do you find that you don't need to review (why?)?

i love the quality of these higher bitrates, but cannot use them because i need to review what i've taken to be sure it's usable. i'm heading off to hawaii in a couple of weeks to shoot a short documentary and there's no way i'm going to shoot hours of footage in remote locations without being able to check my work in-camera.
 
if 1080_24pN avchd and 720_30pN avchd are not possible, at least 1080_24pN mjpeg and 720_30pN avchd would be nice.

but... 24pN is not reliable yet, right?
 
at least this reliable 50Mbps avchd setting was viewable on GH13. for candid video, moment comes and goes. no way to retake same scene again. so not being able to view some settings isnt much issue in that case. in your case, either carry a laptop or use the viewable setting...
 
coming from the hmc150 and always having to transcode, i'm really loving the mjpeg on the gh1. i just don't see much point in shooting with a mode that you can't review, especially since we can't get live monitoring to check our work while we're shooting.
 
different strokes for different folks. for some people, high mjpeg mode worked fine. no transcoding for me while editing. i do NLE from pp cs5. very nice. avchd saves disk space.
 
gmoe said:
This may not be possible but would it be possible to combine your 40Mbps reliable settings for 1080 AVCHD and MPEG and with the settings for the 720p30 patch.

Or is the best way to do it is to upload and switch out firmware depending on your needs?
Click to expand...
Unfortunately, the GH1's firmware uses the same peak bitrate settings for both FHD 1080p and SH 720p AVCHD videos. That makes it impossible to combine my 40Mbps 1080p settings with the 50Mbps 720p settings in the same patch. It is likewise impossible to combine 720p60 and 720p30 AVCHD video modes in the same patch.

However, it is possible to combine the 35Mbps MJPEG settings from my Reliable In-Camera Playback Patch with the 50Mbps AVCHD settings from this Fast Action 720p30 Patch. With that combination of patches, both AVCHD and MJPEG videos would be fully reviewable with in-camera playback.
 
lpowell:
your last statement takes the cake! =)
that seems like the best of both worlds for me and seems like the new preset for your 'reliable' setting. ;)

oops. i take it back. think i'll stick with reliable. i like being able to switch to avchd with 24 and 60p for special projects and films and then to mjpeg with 30p for my broadcast standard and corporate stuff without having to load new firmware. for the special projects, i can use the longer record times (smaller recorded file sizes of avchd) and higher quality...and have the time for transcoding. but for my quick turnaround stuff the mjpeg is much more convenient and a quicker workflow.
 
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lpowell, thanks for your patch. I hope this is a right thread to let you know that I had some card write failures with this patch. I had no problem shooting 1080p in the windy forest. However, today I was recording a webcast off a PC monitor screen for over an hour and have had multiple card write failures and 1 total freeze. (Patriot LX 32GB card, FHD, nostalgic, 1/30 - 1/125, A 1:5.6 -1:9, ISO 100, tripod).
 
Xaveryptak said:
...today I was recording a webcast off a PC monitor screen for over an hour and have had multiple card write failures and 1 total freeze. (Patriot LX 32GB card...).
Click to expand...
Thanks for your report, during testing of earlier versions of this patch, I also saw occasional write-speed failures with 50Mbps AVCHD 1080p recording on my Patriot 16GB SD card. If you continue to have reliability issues with the Fast Action 3-Frame GOP Patch, I'd recommend trying my Reliable In-Camera Playback Patch as an alternative:

http://dvxuser.com/V6/showthread.php?t=219132
 
im guessing this hack removes 60i container for 720p. no pulldown resulting 30pN. i guess that means 30 snapshots taken @1/30 shutter speed to make it progressive. does it mean the recommended shutter speed is 1/30 for normal speed and 1/60 for 2x slow speed? does gh13 still separate out odd lines and even lines? i guess 1/50 is out of question since that might catch the lamp flickering in usa. then convert 30pN to 24pN... if needed.

did i get it right? anyone? thanks.
 
stonebat said:
im guessing this hack removes 60i container for 720p. no pulldown resulting 30pN.
Click to expand...
No, there is no 60i container for the stock 720p60 AVCHD modes, it has always been non-interleaved. What the 50Mbps AVCHD Fast Action Patch does is to simply reduce the 720p frame rate down to 30fps. (The 1080p24 frame rate and its 60i container remain unchanged.)

In 720p30 mode, you can set the shutter speed as slow as 1/30 sec without affecting the frame rate. This can be useful in low-light conditions, though many people prefer to go no slower than 1/60 sec for a more film-like effect.
 
seems to be some confusion about the 180 degree shutter rule and which is more film-like.
according to Barry:
more motion blur (film-like) when shutter = 1/(frame rate). eg: 30p & 1/30th or 24p & 1/24th
less blur (video-like) when shutter = 1/(2Xframe rate). eg: 30p & 1/60th or 24p & 1/48th

the faster the shutter, the more staccato/crisp movement will appear.
the slower the shutter, the more blur and smooth movement will look.

the exception is if you plan to shoot 60p for 24p at 40% slowmo, then you'll want shutter = 1/120th. this is because at 1/60th there will be too much blur when slowed down.
 
i cant digest two replies above. sounds like contradicting.

averan, i think u r talking about interlaced... or progressive segmented frames. i dont think it applies to this gh13 hack as it outputs progressive non-segmented frames. thats why i like panasonic.

lpowell, why is 60th more film like for this 720/30p? is it because every other frame will be dropped to create more jitters? if thats true, how about 50th shutter speed to reduce the jitter a little less? how about 40th? i presume theres no hard written rule about it.
 
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stonebat said:
...why is 60th more film like for this 720/30p? is it because every other frame will be dropped to create more jitters?
Click to expand...
No, there is no frame dropping in 720p30 mode as long as you shoot with 1/30 sec shutter speed or faster.

Back in the film era, the mechanical shutters in motion picture cameras exposed the film for at most half the duration of each frame. Thus, a 24fps camera of this type would have a 1/48 sec shutter speed. If you want to simulate the effect of a film camera operating at 30fps, you'd select a 1/60 sec shutter speed on the GH1. The effects of frame rate and shutter speed on the perceived amount of motion blur can be quite subtle and there are many opinions on what looks best.
 
ah... i see. 1/60s shutter speed doesnt mean camera takes 60 frames and drops every other frames to make 30p. it still takes 30p frames. i can see how 60th can simulate half the duration filming trick for 30p. art of old flick :)

thanks.
 
Hi lpowell, first off, thanks for your continuing amazing work. I am a bit confused as to what this latest patch provides regarding 1080p fhd. Is it the same 3 frame GOP and 50mbps set up as the 720p, still wrapped in the 60i package?
Also, I have played with the patch and am not clear as to why when shooting in mjpeg, I consistently get north of 50mbps, while in either avchd mode, I get considerably lower (around 22mbps) when shooting the same thing (just amateur tests the fibres of a red towel in relatively low light).
 
im perplexed again...

if 60th can give film look by simulating the half duration trick, how to take footage for 2x slow motion? 30th shutter speed?
 
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