You can now download clip Browser 2.6 with Flash Band removal and acquisition data display.
http://support.sonybiz.net/software/detail.aspx?id=BPE-SS-03EW&model=XDZ-P1
The Kata DVG-59 camera glove as seen on my EX3 is now available to buy. More info here.
Over the years there have been many, often heated debates over the differences between 8 bit and 10 bit codecs. This is my take on the situation, from the acquisition point of view.
The first thing to consider is that a 10 bit codec requires a 30% higher bitrate to achieve the same compression ratio as the equivalent 8 bit codec. So recording 10 bit needs bigger files for the same quality. The EBU recently evaluated several different 8 bit and 10 bit acquisition codecs and their conclusion was that for acquisition there was little to be gained by using any of the commonly available 10 bit codecs over 8 bit because of the data overheads.
My experience in post production has been that what limits what you can do with your footage, more than anything else is noise. If you have a noisy image and you start to push and pull it, the noise in the image tends to limit what you can get away with. If you take two recordings, one at a nominal 100Mb/s and another at say 50Mb/s you will be able to do more with the 100Mb/s material because there will be less noise. Encoding and compressing material introduces noise, often in the form of mosquito noise as well as general image blockiness. The more highly compressed the image the more noise and the more blockiness. It’s this noise and blockiness that will limit what you can do with your footage in post production, not whether it is 10 bit over 8 bit. If you have a 100Mb 10 bit HD compressed recording and comparable 100Mb 8 bit recording then you will be able to do more with the 8 bit recording because it will be in effect 30% less compressed which will give a reduction in noise.
Now if you have a 100Mb 8bit recording and a 130Mb 10 bit recording things are more evenly matched and possibly the 10 bit recording if it is from a very clean, noise free source will have a very small edge, but in reality all cameras produce some noise and it’s likely to be the camera noise that limits what you can do with the images so the 10 bit codec has little advantage for acquisition, if any.
I often hear people complaining about the codec they are using, siting that they are seeing banding across gradients such a white walls or the sky. Very often this is nothing to do with the codec. Very often it is being caused by the display they are using. Computers seem to be the worst culprits. Often you are taking an 8 bit YUV codec, crudely converting that to 8 bit RGB and then further converting it to 24 bit VGA or DVI which then gets converted back down to 16 bit by the monitor. It’s very often all these conversions between YUV and RGB that cause banding on the monitor and not the fact that you have shot at 8 bit.
There is certainly an advantage to be had by using 10 bit in post production for any renders, grading or effects. Once in the edit suite you can afford to use larger codecs running at higher bit rates. ProRes HQ or DNxHD at 185Mb/s or 220Mb/s are good choices but these often wouldn’t be practical as shooting codecs eating through memory cards at over 2Gb per minute. It should also be remembered that these are “I” frame only codecs so they are not as efficient as long GoP codecs. From my point of view I believe that to get something the equivalent of 8 bit Mpeg 2 at 50Mb/s you would need a 10 bit I frame codec running at over 160Mb/s. How do I work that out? Well if we consider that Mpeg 2 is 2.5x more efficient than I frame only then we get to 125Mb/s (50 x 2.5). Next we add the required 30% overhead for 10 bit (125 x 1.3) which gives 162.5Mb/s. This assumes the minimum long GoP efficiency of x2.5. Very often the long GoP advantage is closer to x3.
So I hope you can see that 8 bit still makes sense for acquisition. In the future as cameras get less noisy, storage gets cheaper and codecs get better the situation will change. Also if you are studio based and can record uncompressed 10 bit then why not? Do though consider how you are going to store your media in the long term and consider the overheads needed to throw large files over networks or even the extra time it takes to copy big files compared to small files.
I have placed a zip file on my server with 30 seconds of 35Mb/s footage from the PMW-350. It is a short edit so second generation and is saved as XDCAM EX MP4 within the zip file. The original material was shot at an airshow and is 50i. PLEASE PLEASE PLEASE don’t link externally directly to the file. It’s a large file and if I find it being downloaded via direct links on other sites I will remove the file to protect my bandwidth. Please link to this page: http://www.xdcam-user.com/?p=378 if you wish to post about the footage elsewhere. Click here to download the zip file.
I’m currently on the Televisual Roadshow in the UK. Listening to the various commissioning editors and heads of production companies has been an eye opener. For the start the BBC are saying they are very open to new ideas and new concepts, especially shows that introduce a new talent, “format” or style, something they can then license internationally.
The one key thing though that keeps coming up is cost. One BBC commissioning editor stated plain and clear that at the end of a day a cheap idea is more likely to be successful than a more expensive one. Cost to the broadcaster is clearly of paramount importance and the kinds of figures I have been hearing are as low as £25k for a 1 hour HD production.
So how do you make a programme for £25k? Well obviously smart thinking and clever ways of working are going to be essential. But rather than trying to make the show for £25k the alternative is to seek a sponsor for the programme or a company willing to assist with the programme as it would help sell more of their widgets. Think interior design show backed by a DiY chain, things like that. In addition you need to think not just about the TV show but also about a website and web content to accompany the programme, it could be that the sponsor doesn’t directly gain a huge amount from the TV show itself, but the combination of TV show, web site and other media makes the whole proposition much more attractive. The TV stations are keen to work this way as it helps them get more for their money, in fact many of channel 4′s shows are being provided to them for free thanks to sponsorship.
Certainly sponsorship isn’t appropriate for every programme, who would want to back a programme on a controversial subject for example, but it’s certainly worth thinking about if your looking to make broadcast TV shows.
Update: PDW-700 now on BBC’s official approved list.
This is getting very confusing! Last week I was told by several different sources working on productions for Sky HD and the BBC that the BBC & Sky were going to agree to a common minimum standard of 50Mb/s with 1/2? sensors for HD production. Today I hear from a production company that is making HD programmes for the BBC that they were told at the end of last week that 35Mb/s from the XDCAM EX1, EX3 and probably the new PMW-350 is acceptable. Right now there is a lot of confusion over what is and what is not acceptable. I wish the BBC or Sky would publish, in public their HD production guidelines, I was told this would happen last Thursday but so far no-one has been able to find anything. The confusion over what is acceptable makes it impossible to plan productions or make any equipment purchases and this can only harm the industry as everyone holds off waiting to find out what they can or can not use. Come on BBC and Sky… lets us know whether 35Mb/s is acceptable. My guess, reading between the lines is that if you shoot at 50Mb/s 4:2:2 either with a PDW-700/F800 or with an EX with a NanoFlash you will be fine, whatever the BBC or Sky’s decision. I also think that 35Mb/s from the EX’s will be allowed under dispensation or with restrictions to usage and workflow. One thing that appears to be lost in this whole debate is that the EX at 35Mb/s 4:2:0 has the same compression ratio as the PDW-700 with it’s 50Mb/s 4:2:2. The extra bits used by the 700 are taken up by the extra colour information. So in terms of blockyness and robustness through the production chain there should really be little difference between the two. My feeling is that much of the confusion is caused by the older PDW-F350 type XDCAM HD cameras which recorder 1440×1080 at 35Mb/s. This “thin” raster signal causes a lot more problems in post than the full raster of the EX cameras. The re-sizing from 1440 to 1920 (and back in the case of Sky who broadcast 1440×1080) leads to soft pictures and nasty compression artefacts, so I think that these cameras will NOT be allowed while the EX might.
I have been told that the XDCAM EX3 has an improved IR cut filter. I don’t know whether all EX3 have this or whether it was installed at some point during the production run, but the new filter is supposed to reduce the red pollution issue that affects black man made fabrics under certain lighting conditions. I have to say I’ve never found red pollution to be a problem, that might be because I use my EX3 for most things. I’m not in the office at the moment so I can’t test this out, but as soon as I can I’m going to compare my EX1 and EX3 to see if there is a difference.
I’m playing with my EX1 and nanoflash, looking at ways to mount the nanoflash so that it wont compromise the portability of the camera. I’ve found that if I mount it on the rear right side of the EX1 it works really well. Having the Nanoflash on this side helps with the balance of the camera and it dosn’t get in the way. I am powering both the camera and NanoFlash from a single Swit S-8U62 battery. Sorry about the low quality picture. In between jobs so no time to fiddle around.
XDCAM EX1 with NanoFlash
I have been lucky enough to have had a play with the soon to be released clip browser with support for SD files and with Flash Band removal. Another new neat feature is the “Acquisition” display that gives you a real time animated screen showing how the camera was set. You can see the zoom operating, where the focus was set as well as ND, white balance and gamma information. It’s really fun to watch! It will also be useful for diagnosing why footage may be wrong, for example it will be easy to tell if the iris was stopped down too far, thus giving soft pictures.
The New Clip Browser Aquisition Screen
There’s lots of rumors flying around of a pact between Sky HD and the BBC over the minimum acceptable standards for HD acquisition. It’s been known for some time that the BBC wants a minimum bit rate of 50Mb/s and camera sensors that are 1/2 inch or bigger. At the same time there have been many Sky productions produced using XDCAM EX cameras (Road Wars for example) which are shot using XDCAM EX and are 35Mb/s. The BBC have also been using XDCAM EX within many HD productions. Now however it looks like Sky is going to follow the BBC and insist on 50Mb/s for all HD production. 50Mb/s is not a surprise, but what’s being said now is that there will no longer be any exceptions to this rule. So RawCut, the producers of Road Wars are now having to work out ways of shooting at 50Mb/s while still using their existing EX camcorders. The NanoFlash from Convergent Design is an obvious solution.
This new, stricter ruling is not good news as it makes it harder to produce HD programmes with small budgets. If HD is to grow and become the norm for TV production, excessively ridged regulations like this will not help. Surely it would be better if exceptions were allowed. Perhaps following an evaluation or consultation process to allow the use of cameras that fall outside of the 50Mbps, 1/2″ minimum criteria for shows such as Road Wars where filming inside police cars with full size cameras simply is safe or practical.
I’ve seen Road Wars on Sky HD and it always looked fine to me. What will Sky and the BBC’s view be on all the Discovery and National Geographic produced material which doesn’t meet the Sky/BBC specs?
This reminds me of when DVCAM was launched. The BBC and others all announced that DV was unsuitable for broadcast. Well look at SD production now. DVCAM is the workhorse format used by just about everyone for low budget work. The BBC owns thousands of DVCAM camcorders and even has it’s own special “DV Solutions” department. I suspect that once the BBC and Sky realise that they will be closing the door on many interesting HD projects this ruling will gradually disappear into the mists of time.
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