View Full Version : AVC-Intra 100 file question
Stuart Brontman April 10th, 2011, 08:58 PM I rented an HPX-3000 recently and recorded 1080 30p at AVC-Intra 100 codec settings. I recorded all clips at this setting and expected a file size of approx. 1 gigabyte per minute of recording. I'm getting about 1/3 that amount of file size. Did I transfer these files incorrectly? What am I missing here? I know the camera was set at AVC-Intra 100...
Thanks for any help on this.
Daniel Epstein April 12th, 2011, 03:42 PM Do they have a 30PN setting which might get you about halfway there? No that wouldn't be it. The camera doesn't do 720. Did you transfer the files incorrectly? Are they working properly? Does P2CMS tell you anything about them? Are you looking at the native recording files or some kind of transfer which might have compressed them. If they are working and the original files the most likely answer is you didn't record in 100 but 50.
Stuart Brontman April 12th, 2011, 03:54 PM I'm not sure, but I'm 99% certain we had it set at standard 30p (wrapped in 60i). Either way at AVC-Inta 100 the file size should be about 1 gig = 1 minute based on what I've read.
Daniel Epstein April 12th, 2011, 03:57 PM see my edited reply above
Stuart Brontman April 12th, 2011, 04:08 PM I put the P2 cards in the reader and directly transferred them to my RAID system. The files are labelled with the mxf extension. Some of the files seem appropriate size-wise, but the video quality is also way too soft for such a great camera. Playback from the camera (and the P2 cards) looked great on the Panny 17" monitor the day of the shoot, but in my studio it's soft. I am 100% positive my focus was spot on. The footage is usable, but way below what should have been obtained from this camera.
The tech handling the setup either made incorrect menu settings or the camera is having some sort of electronics glitch. I'm meeting with the rental group tomorrow to review the footage and see if we can figure out what happened.
It's quite frustrating...
Daniel Epstein April 13th, 2011, 08:39 AM Hey Stuart,
Real basic question. When you transferred the files from the card you copied the Contents Folder and Last Clip.TXT complete without going any deeper in the folder structure correct? Do you remember the amount of Data which was on the cards? Did that end up being the same size as on your raid? If those match up then you are dealing with camera settings for file size. If the size doesn't match then you may have an incorrect transfer. If you are on a mac you really shouldn't be looking at the mxf files directly. Also some kinds of computer playback of files do not do justice to the video. Are you looking at the footage with you edit system software or something else?
Stuart Brontman April 13th, 2011, 08:50 AM Thanks Daniel. It turns out many of the files seem to match size-wise to the expected length of the clip. I'm on a PC and have viewed the mxf files directly in After Effects and Premiere (both CS5). I have also converted to Cineform 10 bit files. When burned to blu-ray and displayed on a 46" 1080 LCD they are soft, but passable after some work with unsharp mask and Neat Video's great little plug-in. Unfortunately I'm concluding the settings were incorrectly input during menu setup. My guess is detail settings were way too low. On a green screen shoot I know that's usually not a bad thing, but this footage is just way too soft for a camera of this caliber. My XH-A1 does better work than this on the perceived sharpness side. I've corresponded with others using this camera for green screen work. They use default factory settings, get a super-sharp image, and pull a great chroma key.
I'll be going to the rental house today to determine if there was a camera glitch... They're concerned as well since they have an upcoming rental on the camera next week.
Stuart Brontman April 13th, 2011, 12:40 PM It looks like the problem was improperly adjusted back focus and possibly detail settings being too low. This was a painful lesson on the need to insist on sufficient setup time prior to the shoot. There was a lot of time pressure being exerted on us which opened the door for mistakes like this. Never again. The footage is usable, but it could have been better. It kind of looks like 720p footage being used in a 1080p production. Usable, but a touch soft.
Live and learn, no matter how painful it is.
Daniel Epstein April 13th, 2011, 03:50 PM Hey Stuart,
Sorry to hear your camera had set up and back focus issues. Back focus can really ruin great stuff. Often more important than Codec used to record the footage. Other issues to consider when it comes to 30P is shutter on some of the Panasonic cameras default to the frame rate not 1/2 the frame rate. I certainly have been in the situation of needing to shoot and settings are not optimal but you shoot anyway. I never trust rental companies to correctly adjust back focus or tightness of lens as too many times they are not perfect. Checking out rental gear properly takes time but I have been burned when I didn't do it.
Also just to be clear you are saying the size of the files wasn't too small. It was the quality of the footage which made you think it was more compressed than you thought it would be.
Stuart Brontman April 13th, 2011, 05:27 PM Yes, the footage quality made me think the compression was incorrect. The first take was done at a lower bitrate setting, but the later ones were correct. Unfortunately the back focus issues completely offset the AVC Intra-100 bit rate. I've got an EX-3 from the same rental group for a shoot tomorrow and you can bet it's getting a thorough check-out before I arrive at the client.
Robin Probyn April 13th, 2011, 07:18 PM Yes another good reason to own your own gear.. piece of mind re set up and back focus etc..
Stuart Brontman April 13th, 2011, 08:43 PM I hear you, but the HPX-3000 is way out of my price range! I still get great footage with my trusty XH-A1 and Cineform conversion. Not HPX-3000 potential, but good enough to satisfy my industrial clients. Then there's the little wonder Panny TM-700. In good lighting it's a nice little camera for industrial stealth work. For green screen neither will do... But yes, given a choice I'd rather own anyday if money were no object. With the EX-3 I'm using tomorrow I've spent the past 3 hours checking settings and analyzing footage. There will be no problems this time. I've got this hooked up to a Nanoflash unit and found I need 140 Mbps to really show much difference with the HQ footage coming off the EX-3. That's quite a testimony to the EX-3 and its native 35 Mbps recording mode.
Robin Probyn April 14th, 2011, 02:14 AM Yes 3000 is pricey .. and the 3100 is a much better bet now IMO.. and way cheaper.. I also have a Nanoflash which I hook up to a HDX900.. works well.. but so far Ive never shot over 100 Mbps with it..
Yes BF can a real pain.. I hate having to use my lens on another camera.. because Iam twitchy about re setting it on my camera ..
Good luck with your shoot..
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