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-   -   370 doesn't meet PBS requirements? (https://www.dvinfo.net/forum/panasonic-p2hd-dvcpro-hd-camcorders/489503-370-doesnt-meet-pbs-requirements.html)

Philip Fass December 30th, 2010 06:57 AM

370 doesn't meet PBS requirements?
 
Looks like there's no hope of PBS acquiring a video shot on an HPX370, according to this document:

http://www.pbs.org/producers/TOS-1-2...ion-to-PBS.pdf

Basic problem is that chip has to be at least 1/2 inch. Any thoughts to the contrary? Thanks.

Caleb Reynolds December 30th, 2010 07:47 AM

Man that document is heady. What if you shoot a documentary and later PBS wants to show it? Lets say its in HD 720p. But was shot on a HPX200. Does that mean PBS simply WON'T show it?

By heady, I mean since I'm newer to the DP side of my films/projects, I have a-lot of learning to do.

Gary Nattrass December 30th, 2010 08:25 AM

The world is changing though and with the BBC in the UK now accepting the canon XF300/305 a 1/3" chip camera it looks like the codec is far more important than chip size.

That document is probably from research before the HPX300/370 and the canon cameras were released so is like the BBC one and out of date:http://www.bbc.co.uk/commissioning/p...d_delivery.pdf

I have done numerous broadcast shoots on my HPX301 and used it and another as a B-cameras to the 2700 and the 3700, I have yet to find anyone who can spot which shots came from which camera in the edit and as it is all in AVC Intra 100 the workflow is seamless from all three camera's.

Most broadcasters have their base specifications but it doesn't totally dismiss every camera purely on chip size, its all down to budget and programme requirements.

Philip Fass December 30th, 2010 08:49 AM

Gary, your 3rd paragraph is quite an endorsement of the 370! If it's capable of footage that's indistinguishable from a $60K camera, it must be great value for the money.

Gary Nattrass December 30th, 2010 09:08 AM

Don't get me wrong the HPX301 isn't a replacement for the 2700 or 3700 but used under the right conditions it cuts in very well. I've also done indie features on the the 301 and it looks very nice on the big screen too.

It still has the limitations of cmos and small chip skew etc but I use mine for broadcast all the time or when budget isn't there for the 2700 or 3700, I am just very careful to know its limitations and make sure it has enough light and I don't do anything silly with it. At least when I hand over the footage I also know that the AVC Intra 100 codec isn't going to give any problems in post too.

Philip Fass December 30th, 2010 09:58 AM

I'm in the middle of one project and planning another. I'd use the 370 exclusively for the new one, but the current one has been shot so far with a Canon XL H1, HDV, 1080i. Would it be easy to keep the same "look" with footage from the two cameras?

Gary Nattrass December 30th, 2010 11:33 AM

Not sure as I don't know the canon XL camera at all, I had two HDV camera's last year the Z7 and S270 but the 301 is far better and cleaner looking than they were.

It may be that if you shoot with the 370 set to 1080 AVC intra 50 that it will be more compatible with HDV, best do some tests first and another option would be to shoot full def on the 370 but I suspect you will be downgrading it to match the HDV footage.

Glen Vandermolen December 30th, 2010 05:07 PM

I don't know about PBS, but Discovery HD recently aired a documentary called "Finding Amelia." A lot of the footage was from an HPX370.

The BBC did accept the XF300/305, but they did NOT accept the HPX300. I don't know about the 370. I've heard Discovery HD also accepts the XF300, but I haven't had anyone confirm this.

It's more than just the codec, or the HPX200 would have been accepted years ago. Supposedly the Canons make incredible images, 1/3" or not.

David Heath December 30th, 2010 07:33 PM

AFAIK the BBC have approved the XF305 basically for self-shooting work, as a modern high-def equivalent to the Z1 if you like. (The latter was only ever approved by them for standard definition - not in HDV mode.) That's not the same as a blanket approval, and I believe it's been approved on it's own merits - not that it's likely to herald any general acceptance of 1/3" (Though it may not be the last 1/3" camera.)

It's also worth noting that the guidelines will allow a certain amount of non-HD material in an HD programme if it's use is editorially justified - and non-approved cameras can fit into this bracket. An obvious example would be to allow use of archive, or other "special interest" footage. That's very different to such as interviews shot specifically for the programme, when non-approved cameras wouldn't be allowed.

The problem with the 300 series cameras is that they are inherently noisy. And HD broadcast transmission coders don't like noise. The pictures from them may look fine in the edit - but not stand up as well in the chain. That's especially true if any gain was to be used.

The 370 tried to get over the problem of the 300 by using quite aggressive electronic noise reduction, both within the frame, and also over several frames. It worked OK a lot of the time - but gave a fairly unpleasant effect sometimes on moving objects which seemed to be followed by a trail of noise. It may not have been too bad in itself much of the time, but severely compromised any attempts at post work. The worst example that was shown to me involved a chroma keying example, and whilst the effect wasn't too bad on the original footage, the end result was awful.

Glen Vandermolen December 30th, 2010 08:46 PM

Quote:

Originally Posted by David Heath (Post 1603173)
AFAIK the BBC have approved the XF305 basically for self-shooting work, as a modern high-def equivalent to the Z1 if you like. (The latter was only ever approved by them for standard definition - not in HDV mode.) That's not the same as a blanket approval, and I believe it's been approved on it's own merits - not that it's likely to herald any general acceptance of 1/3" (Though it may not be the last 1/3" camera.)

Agree on the general acceptance of 1/3" cameras.
The BBC approved the XF300/305 for full acquisition for independent productions, along with the RED and the Sony PDW 700 & 800. That's pretty good company. The BBC DV Solutions Unit recently bought 50 XF305s, maybe for the self-shooting work. They will replace the Z1s.

As far as future broadcast quality 1/3" cameras, will they continue to improve, or is this the last of the line? Is the XF305 as good as it will get? Can anyone forsee a follow-up to the Canon XF and Panny HPX370 cameras, or will the manufacturers abandon 1/3" chips and pursue large sensor cameras, ala the AF100?

And what does this have to do with the 370 and PBS? I dunno, this thread has derailed a bit.

Ed Dooley December 31st, 2010 12:43 PM

So the only important thing is to convert your HPX-370 program to the Sony codec, submit it and make sure you have a friend with the appropriate Sony camera in case PBS asks you what you shot it with. :-)
Ed

David Heath December 31st, 2010 08:35 PM

Quote:

Originally Posted by Glen Vandermolen (Post 1603198)
As far as future broadcast quality 1/3" cameras, will they continue to improve, or is this the last of the line? Is the XF305 as good as it will get?

The question might be "what's the point?"

In the past the real reasoning behind 1/3" cameras has been size/weight/price. If those criteria can be met with larger chips, less stressful on the underlying physics, then what's the point of 1/3"?

That really is the triumph of the EX, isn't it? It got 1/2" chips into a size/weight package normally associated with 1/3", at a comparable price point. Why therefore give your engineers a hard job, when they could just use 1/2" (or bigger) chips?

Glen Vandermolen January 1st, 2011 07:13 AM

Quote:

Originally Posted by David Heath (Post 1603437)
The question might be "what's the point?"

In the past the real reasoning behind 1/3" cameras has been size/weight/price. If those criteria can be met with larger chips, less stressful on the underlying physics, then what's the point of 1/3"?

That really is the triumph of the EX, isn't it? It got 1/2" chips into a size/weight package normally associated with 1/3", at a comparable price point. Why therefore give your engineers a hard job, when they could just use 1/2" (or bigger) chips?

Good question. Panasonic has stated they will not use 1/2" chips. Canon went with 1/3" chips because of the better zoom range on the XF300. There'll still be a need for 1/3" cameras for the lower budget range.

Alister Chapman January 3rd, 2011 12:07 PM

The problem with small sensors is that you run up against diffraction effects. For 1920x1080 HD cameras this means that your smallest useable aperture is around f5.6. At F8 you will see softening of the image. This is down to the way light behaves when passing past a sharp edge (the iris) and the laws of physics. It doesn't matter how good the sensor is. Add to that the difficulty of making high quality fast zoom lenses and you end up with a camera that is typically only useable between f5.6 and f2.8, that's just a 3 stop range. At a push by going to f8 or if your lens is very fast you might gain another stop, but as most lower cost lenses are not constant aperture and often a little soft when fully open it's a pretty narrow range to have to work within. ND filters can mitigate this to some extent, but constantly switching filters is tiresome and many camera operators (PA's, runners, you name it) using handycams have no idea of the importance of staying within the exposure sweet spot. In many cases they just switch the camera to auto. As HD becomes more and more prevalent in news and current affairs and viewers become used to seeing high quality full HD in their homes this is an issue that will get noticed more and more. I think going forward what we are likely to see is improvements in single sensor technology. If you can eliminate the prism cameras will be smaller and lighter, lenses will cost less to make. Even a 1/2" sensor could be put into a very small camera. You only have to look at the size of the NEX-VG10 with it's 35mm sized sensor to see what's possible.

Ed: there was a production company based in the UK that were commissioned to make a broadcast TV show. They were given the required minimum tech specs at the start of the project but cheated using an inferior codec on location and then bumping it up to a better codec in post. They got caught, and were sued for a very substantial sum of money for breach of contract. Engineers can tell the difference between codecs, each one has it's own tell tale signature such as macro block size, motion vectors or sampling. In addition there is the metadata and file headers that should accompany the rushes and this normally includes the camera and codec type. Think very carefully before trying to pass off sub standard footage as something else, it is fraud after all and it could come back and bite you.

David Heath January 3rd, 2011 01:23 PM

Further to what Alister says, there is a way of improving lens performance with small chips which has something to do with making the ray paths parallel at a certain point in the lens. The effect is that the actual physical aperture sixe becomes larger than it would be in a conventional lens for a given f stop, hence reducing the diffraction effect.

But (strangely enough) the drawback is complexity, and hence cost etc. I believe Canon use the trick in the XF305 (which may be a reason why such as the BBC will accept it, but no other 1/3" camera) - but the XF305 is over £1,000 dearer than the EX1. As I said before - why give your engineers a hard job, when they could just use 1/2" (or bigger) chips?

If 1/2" meant a large shoulder mount form factor, I can see why it may be worth persevering with improving 1/3" designs. As it is (the proof being the EX), what's the point? Why not make your life easier and go for a 1/2" design?


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