PDW 700 Native White Balance

The PDW-700 cameras are balanced for daylight optically and then corrected electronically for tungsten etc.

Traditionally cameras were balanced for Tungsten and then added colour correction optical filters to get to daylight. This was done as CC filters absorb light and thus make the camera less sensitive. Normally when shooting outdoors in daylight sensitivity is not an issue while shooting indoors under tungsten light you used to need every bit of sensitivity you could get.

The down side to this approach is that tungsten contains very little blue light so to get a natural picture the blue channel was often running at quite a high level of gain which increases noise in the blue channel and thus overall noise. In addition when you rotated in the CC filters to get to daylight the sensitivity of the camera was reduced, so you did not have constant gain.

With the PDW-700 (and also the F350 I believe) the cameras are essentially balanced for daylight, without the use of any CC filters, which helps reduce noise in the blue channel. Then for tungsten shooting you electronically re balance the camera. By doing this the overall sensitivity of the camera is constant whether shooting at 3.2K or 5.6K and you only get additional blue channel noise while shooting under tungsten. If you are worried by blue channel noise you can always correct from daylight down to tungsten with an optical CC filter (80A) and leave the camera set to daylight, although this will reduce the systems overall sensitivity by around 1 and a half stops.

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Chasing Vulcans.


Last weekend was the Royal International Air Tattoo. The largest military air show in the world. I’ve filmed this event many times and every year we try to do things a little differently to jazz things up. We have been shooting the show in HD for the past 3 years, this year it was entirely XDCAM with the exception of the minicams which were HXR-MC1P HD minicams. We had an EX1, EX3 and 3x PDW-700?s. As well as the usual extra long telephoto lenses we had a couple of gyro stabilized lenses including a schwem gyrozoom. While not an HD lens we found that the performance of the lens wasn’t too bad. There is no other lens that offers the degree of stabilization offered by the schwem so for the applications we were using it for we were happy to accept the slight softness in the corners. The application we had was to use it in one of the “Follow Me” vehicles used to marshall the aircraft around the airbase.

The high point of this was doing a tracking shot of the recently restored Vulcan bomber landing at Fairford. To do this we drove along the taxiway parallel to the runway at high speed as the Vulcan came into land. Once it had landed we got some impressive shots as it taxied right behind us. The Vulcan is a huge aircraft and to have this bearing down on you as it taxies with all four engines running (they normally use only 2) is quite a rush! The Schewm is a long lens so the Vulcan completely filled the frame, despite this the gyro stabilisation kept the images rock steady. Over the weekend I shot aircraft startups and GV’s using an EX3, then the follow me stuff with the schwem and PDW-70 as well as flying and display footage using a PDW-700 and 42x Fujinon lens. The most reassuring thing is that as these are all XDCAM cameras we know they will all cut together well in the final edit.

PDW-700 or PDW-F800 viewfinder choice.

The PDW-700 and F800?s are sold body only, so you have to choose which viewfinder you want. there are 3 choices. A cheap HDVF 200 mono CRT finder that is 480+ lines resolution, the mid range (top of the CRT range) HDVF-20A which is 500+ lines resolution and then there is the expensive colour HDVF-C35W.?I got the HDVF-20A. The viewfinder is a critical part of the package and I wanted a good viewfinder. For the past year my main camera has been my trusty EX3 which I love. This has a really good colour viewfinder with an excellent colour peaking function and image magnification. When I use my EX3 it is rare for me to not get my pictures pin sharp and spot on in focus. Plus I can frame my image taking into account both black and white contrast range and colour contrast. With the EX3 judging exposure is easy, you can see when your overexposing as you can see colours washing out. If I don’t want (or can’t) take a colour monitor on location then I really can light an interview or check colour balance without just using the EX3?s finder.?Now with the PDW-700 I am struggling. Going back to a mono CRT has been a bit of a shock, to be honest I am struggling with it. It’s not that there is anything wrong with the HDVF-20A but I have become used to working with a colour VF. I’m not sure I can live with the CRT VF for very long. I guess I am going to have to start saving my pennies as I think going back to a mono CRT is a retrograde step. I just wish the C35W was a little cheaper. Perhaps Sony could bring out a VF for the 700/F800 based on the rather good EX3 finder.?If I was making the purchase again I would opt for the more expensive C35W. I no longer see a colour VF as a luxury but more of an essential item. When you work with cameras day in – day out you want the tools that make your life as easy as possible and a good colour VF is one of them. On it’s own the C35W may seem expensive at £5.5k compared to the £3.5k of the 20A, but in terms of the total packing it’s another 10% to the cost but in retrospect I think it would have been worth it.

Chroma Key Shoot with PDW-700

Just got back from my first PDW 700 green screen shoot. We were in a tiny room and it was a hot day, so it was certainly warm! Everything went well although I have to say that I am really struggling with the CRT viewfinder. I have become so used to a full colour viewfinder on the EX3 that it really is horrid going back to a monchrome viewfinder. I shall be playing with the footage on Monday so I’ll let you know how well it keys then.

BBC Hints at XDCAM EX approval for broadcast HD production.


The BBC’s Danielle Nagler’s keynote speech at the HD Masters strongly hinted at the BBC accepting the use of the Sony EX1 and EX3 for mainstream HD broadcast production. I’ve always said that the EX cameras are remarkable cameras and this just backs up my assertion that the EX is good enough for broadcast. Danielle showed footage of an EX cut with a HDCAM camera commenting that “what this small camera can deliver is a breakthrough, allowing us to consider the migration of a much, much wider range of BBC programming than has previously been possible.”

You can read the full transcript here:

http://www.bbc.co.uk/blogs/bbcinternet/2009/06/hd_masters_conference_keynote.html

XDCAM EX Cinegammas

I have been doing a lot of research into the best gammas to use on the EX’s for different lighting situations. The cinegammas are designed for shooting footage that will be graded, the images they produce are not entirely natural looking, however they do maximise dynamic range by compressing highlights and at the same time allocating a large part of the recorded signal range to mid tones and shadow detail. This is why shadows can look washed out or milky. However this also gives you more to play with in the grade.

Cinegamma 1 is tailored for shooting bright scenes or scenes where there will be large areas of highlights. CG1 is tailored for maximum highlight handling with lower shadow dynamic range compared to CG3 and CG4.?Cinegamma 2 is essentially the same as CG1, except the overall level is reduced making it broadcast safe at 0db. Cinegammas 1,3 and 4 all record up to 109% at 0db and 104% at -3db.?Cinegamma 3 has strong highlight compression but the compression starts later than CG1 so it’s not as compressed as CG1. Midtones and shadows are stretched more than CG1. This gives more dynamic range to mid tones and shadows compared to CG1 at the expense of some highlight handling.?Cinegamma 4 is similar to CG3 but with the mid tones lifted still further so that it gives a brighter looking picture overall.

My preference is to use CG1 for outdoor, brightly lit scenes or scenes where highlight handling is critical. Then I use CG3 for indoor and scenes on dull days where extreme highlight handling is less critical, but shadow detail becomes more important. What I have also found is that when shooting interviews the cinegammas work best when they are slightly under exposed compared to standard gammas and then graded in post. If using cinegammas I tend to expose skin tones at around 60%.

Cinegamma 1 on the EX is the same as Hypergamma HG4 on the PDW-700, F900R etc and cineegamma 2 is the same as Hypergamma HG2. With CG1/HG4 : 460% D-range is compressed to 109%.

Setting BOTH zebras on an XDCAM EX, very confusing!


If you set zebra 1 to 60 and then set zebra 2 to 90, then go back to zebra 1 you will find that the displayed value of zebra 1 will now be 90, however provided you don’t make any changes to zebra 1 if you go down to BOTH zebra 1 will work at 60 and zebra 2 at 90.

The thing is that going back to Zebra 1 (or zebra 2) and make any changes you select selects Zebra 1 (or 2) only, ie a single zebra and in doing so sets the level to the last level set. It’s only by going to BOTH that you enable both zebras together.

So to set two indendent zebras first set zebra 1 to your required level, then set zebra 2 to your required level, final scroll down to both and select. Now you zebras will be working at the independent levels you set, even though this may not appear to be the case in the menu.

It’s not the most logical way to lay out the menu as it does not show you both settings together at any point, hence the understandable confusion, but you will find that both zebras will work at the independent levels you set.

Camera setup, reviews, tutorials and information for pro camcorder users from Alister Chapman.