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This was a question that came up very often at TecExpo in Chennai. “How do I use the zebra’s for exposure”?

Well, first of all let me say that I am not a big user of Zebra stripes. Instead I tend to rely on correctly setting up the viewfinder (using colour bars) and judging exposure that way.On most pro camcorders the default zebra setting is 70%, so when your exposure hits 70% of peak white (100%) a striped pattern is superimposed on the image. Most zebras have a 10% window, so the stripes start to appear at 65% and then go away again at 75%. Why 65-75%? Well this is generally accepted as the correct exposure range for faces and skin tones, so in an ideal world a face with zebra stripes on it will be exposed correctly. However we don’t live in an ideal world so this doesn’t always work, shiny reflections or particularly dark skin tones can be misleading and even if the face is correct, what about the rest of the scene?

Another way to use the Zebra’s is to set them to 100%. By setting them to 100% as you get very close to peak white (95%) you will start to see the zebras. This acts as a warning that areas of the image are about to over expose or may be over exposed. I find this a much more useful way of using the zebras as it is really important to know if your image is going into clipping and limiting at 100%. Once any image information is lost due to over exposure, no amount of post production will ever recover it. A face that is a little under or over optimum on the other hand can be corrected for in post production.

I was asked by one of this blogs readers about my thoughts on this. It’s certainly a subject that I have spent a lot of time thinking about. Traditionally broadcast and television professionals have used large and bulky cameras that use 3 sensors arranged around a prism to capture the 3 primary colours. The 3 chip design gives excellent colour reproduction, full resolution images of the very highest quality. It’s not however without it’s problems. First its expensive matching 3 sensors and accurately placing them on a high precision prism made from very exotic glass. That prism also introduces image artefacts that have to be dealt with by careful electronic processing. The lenses that have to work with these thick prisms also require very careful design.

Single sensor colour cameras are not something new. I had a couple of old tube cameras that produced colour pictures from a single tube. Until recently, single chip designs were always regarded as inferior to multi-chip designs. However the rise of digital stills photography forced manufacturers to really improve the technologies used to generate a colour image from a single sensor. Sony’s F35 camera used to shoot movies and high end productions is a single chip design with a special RGB pixel matrix. The most common method used is by a single sensor is a bayer mask which places a colour filter array in front of the individual pixels on the sensor. Bayer sensors now rival 3 chip designs in most respects. There is still some leakage of colours between adjacent pixels and the colour separation is not as precise as with a prism, but in most applications these issues are extremely hard to spot and the stills pictures coming from DSLR’s speak for themselves.

A couple of years ago Canon really shook things up by adding video capabilities to some of their DSLR’s. Even now (at the time of writing at least) these are far from perfect as they are at the end of the day high resolution stills cameras so there are some serious compromises to the way video is done. But the Canons do show what can be done with a low cost single chip camera using interchangeable lenses. The shallow depth of field offered by the large near 35mm size sensors (video cams are normally 2/3″, 1/2″ or smaller) can be very pleasing and the lack of a prism makes it easier to use a wide range of lenses. So far I have not seen a DSLR or other stills camera with video that I would swap for a current pro 3 chip camera, but I can see the appeal and the possible benefits. Indeed I have used a Canon DSLR on a couple of shoots as a B camera to get very shallow DoF footage.

Sony’s new NEX-VG10 consumer camcorder was launched a couple of weeks ago. It has the shape and ergonomics of a camcorder but with the sensor and lenses of a 4/3″ stills camera. I liked it a lot, but there is no zoom rocker and for day to day pro use it’s not what I’m looking for. Panasonic and Sony both have professional large sensor cameras in the pipelines and it’s these that could really shake things up.

While shallow DoF is often desirable in narrative work, for TV news and fast action its not so desirable. When you are shooting the unexpected or something thats moving about a lot you need to have some leeway in focus. So for many applications a big sensor is not suitable. I dread to think what TV news would look like if it was all shot with DSLR’s!

Having said that a good video camera using a big sensor would be a nice piece of kit to have for those projects where controlling the DoF is beneficial.

What I am hoping is that someone will be clever enough to bring out a camera with a 35mm (or thereabouts) sized sensor that has enough resolution to allow it to be used with DSLR (or 4/3)  stills camera lenses but also be windowed down and provided with an adapter to take 2/3″ broadcast lenses without adding a focal length increase. This means that the sensor needs to be around 8 to 10 Mega Pixels so that when windowed down use just the center  2/3″ and it still has around 3 million active pixels to give 1920×1080 resolution (you need more pixels than resolution with a bayer mask). This creates a problem though when you use the full sensor as the readout of the sensor will have to be very clever to avoid the aliasing issues that plague the current DSLR’s as you will have too much resolution when you use the full sensor. Maybe it will come with lens adapters that will have to incorporate optical low pass filters to give the correct response for each type of lens.

A camera like this would, if designed right dramatically change the industry. It would have a considerable impact on the sales of traditional pro video cameras as one camera could be used for everything from movie production to TV news. By using a single sensor (possibly a DSLR sensor) the cost of the camera should be lower than a 3 chip design. If it has a 10 MP sensor then it could also be made 3D capable through the use of a 3D lens like the 4/3″ ones announced by Panasonic. These are exciting time we live in. I think the revolution is just around the corner. Having said all of this, I think it’s also fair to point out while you and I are clearly interested in the cutting edge (or bleeding edge) there are an awful lot of producers and production companies that are not, preferring traditional, tried and tested methods. It takes them years to change and adapt, just look at how long tape is hanging on! So the days of the full size 2/3″ camera are not over yet, but those of us that like to ride the latest technology wave have great things to look forward to.

Panasonic HDC-SDT750

I’m a bit late on this as I’ve been away, but Panasonic have announced a stereoscopic micro 4/3′s lens for their camera range as well as a consumer S3D camcorder (well it’s actually a 2D camcorder with a conversion lens). The Panasonic 3D lens incorporates 2 lenses and is designed to work with the Lumix G micro system. It’s primarily a stills lens, but with the right firmware the cameras may also be able to shoot 3D video.

Panasonic have also released details of their HDC-SDT750 3D camcorder. This is a 3 chip 2D camcorder that can be fitted with a 3D conversion lens that allows it to shoot side by side 3D images. The left and right images are then squashed horizontally by 50% and recorded as a single 1920×1080 video clip that contains the two squashed images side by side. This has the advantage that when plugged in to a consumer S3D TV via HDMI the TV will show the footage in 3D (or stereoscopically to be correct). The down side is that each view only uses  960×540 pixels during capture, so it’s not full HD for each eye. On screen it probably looks better than this sounds as each eye is seeing slightly different images and this gives the impression of slightly higher resolution than that of a single image. What is exciting to me about this camera is it’s very narrow interaxial of about 30mm. This will make it suitable for POV and handheld video diary type shots, something not really possible with larger interaxials or beam splitter rigs. So even though the resolution may not be there, I can see one of these cameras finding it’s way into my camera kit. I’d certainly love to get one to review.

Anyway these are both very interesting and only goes to show just how quickly S3D is being developed. When consumers start to become used to seeing their home videos in S3D, we professionals are going to have to start producing more and more content in S3D.

IBC is just over a month away and I expect we will see lots more 3D products between now and then, including some more of my Hurricane 3D rigs

Oh… one more thing.. the camera does 1920×1080 50P!!

My 3D rig now has a name, we are calling it the Hurricane rig. It needed a name so that when talking to the design team and factory they know what we are talking about. I have a deal worked out with a well known, high quality brand for production and distribution of the rig world wide. I can’t give away too many details at this point but the rig will work with a broad range of cameras from DSLR’s up to Sony P1 compact studio cameras. It’s ideal for EX’s and Canon XF305′s etc. It’s a beam splitter rig with some clever tricks that make it extremely portable and very versatile. The aim is to produce the one and only 3D rig you’ll ever need. The  base rig will have manual control of interaxial and convergence along with adjustments for camera roll, tilt and height. A series of add-on and upgrade kits will also be available to add full servo control of interaxial and convergence, lens control and optional brackets for the Nano3D and Transvideo Cinemonitor 3D monitors.

A prototype has been built and used on several 3D stereoscopic productions so we know the design works. We are now working on the final CAD drawings and a pre-production unit  before going in to full scale production.

As anyone that understands optics will know the most important aspect of a mirror or beam splitter rig is the mirror itself. The mirrors we are using in the rigs are top quality optically flat mirrors with one of the very best coatings on the market. We have a true 50/50 split with negligible colour shift. Despite the high quality and relatively high cost of the mirrors we hope that the final price of the rig will surprise and amaze. My aim is to produce a rig that will make top quality 3D production available to everyone without breaking the bank.

Included with the rig will be a voucher that will enable you to get a low cost training DVD or discounted training course that will get you up and running very quickly, with as little fuss as possible.

Why use a mirror rig?

While Sony and Panasonic are working on one piece stereoscopic video cameras, these will always have limited applications. The key to good 3D production is the ability to adjust the interaxial or camera lens separation. For the majority of productions the camera interaxial will be below 70mm and very often, for 3D that is easy on the eyes, less than 50mm. For some scenes you may even be down to 25  to 30mm! However for scenic shots you may need greater separation, say 100mm or more. You just don’t get this flexibility with a twin lens camera. In addition a dedicated 3D camera will be an expensive piece of kit and may well not be suitable for conventional 2D. So when your not shooting 3D it will sit on the shelf gathering dust. Meanwhile the cameras from a beam splitter rig, are after all just a pair of 2D cameras so they can also be used for your 2D productions. If you already have a single camera, ten all you need to do is hire or buy a second camera and the rig. This will be far more cost effective than a dedicated 3D camera.

This isn’t a review, I have not had a play with one yet. I just wanted to discuss the camera in more detail than I have previously. The PM-320 on the outside is almost identical to the PMW-350. The only clues as to the cameras identity are a blue rubber grip under the camera handle and a slightly blue XDCAM badge on the side of the camera. I’m pleased that Sony have done this rather than making the camera some horrid light grey as they did with the PDW-330. Inside the box instead of the 2/3″ sensors of the PMW-350 you get the same 1/2″ sensors that are fitted to the EX3. The camera uses the same 1/2″ hot shoe lens mount that’s fitted to other Sony 1/2″ cameras like the DSR-300 or PDW-355. This would make the PMW-320 an interesting upgrade option for original XDCAM HD camera owners. Unlike the PMW-350, standard definition is included as standard, so no need to buy an additional dongle. The 320 uses the same menu structure as the 350 (which I really like) and has the same Cinealta type scene files as opposed to the picture profiles of the smaller EX cameras. These scene files use Hypergammas as opposed to Cinegammas and have a greater range of adjustments. Picture quality should be pretty much the same as you get from an EX3 but the extra ND filter and possibly a better lens may give the 320 a tiny edge in some circumstances, but I think overall it will be pretty much impossible to tell the difference. One thing to note is that the lens on the EX3 has an image stabilizer, while the lens fitted to the PMW-350 does not. At NAB the 320′s were being shown with the same lens as the 350 so it seems likely IMHO that the production 320 packages will not have an optical image stabilizer.

The shoulder mount design does make it easier to hold the camera steady when handheld, so the lack of a stabilizer is not necessarily a big deal. For many the form factor is what will be attractive. The PMW-320 looks and feels like a “proper” camera. This is important, there are some Hollywood actors that won’t allow themselves to be filmed unless it’s by a full size camera (sad) and when your shooting a corporate video the client often expects to see a large camera. Sitting, price wise, closer to a PMW-350 than an EX3 the 320 might be a hard sell. You do get the shoulder mount form factor, 4 channels of audio, a radio mic slot and SD, but for most applications there will be no difference in image quality. If you can get away with the EX3′s (or even EX1′s) form factor, why spend all that extra money on the PMW-320? If your looking at spending that kind of money, I think you would be better off going all the way to the PMW-350. This then adds a better sensor block producing a really stunning, low noise image with remarkably little grain. It also gives you the industry standard B4, 2/3″ lens mount, opening up the ability to directly fit a massive range of lenses that can be hired from most broadcast rental companies. 2/3″ also has a noticeably shallower DoF giving you more creative control.

Kata CC-196 Camera Bag

One thing that I have been asked for a lot recently is to suggest a bag for the EX3 that can be taken on an aircraft as carry-on. The EX3 is a little tricky as you can not remove the viewfinder and this makes the shape a little awkward. I have consulted with my friends at Kata and they recommend the CC-196 as a compact carry-on run and gun style bag. I have not used this bag myself but Kata make good camera bags and the CC-196 is clearly large enough to take an EX3 while still meeting most airlines carry on regulations. If you don’t need to comply with the carry on rules then you can use the Kata VB-510 backpack which looks very cool with lots of compartments including one for a laptop as well as a neat work mat.

Well one of the big NAB announcements was the intention by Sony to release a compact 35mm equipped camera. A prototype unit was briefly shown at the press event but little details were given. I’ve been trying to find out more but Sony are being very tight lipped. It was announced that it will be available prior to next NAB, so that means that there is likely to be some other launch event in, at my guess 6 to 8 months time, of course there may be more news before then. Last year Sony announced the PMW-350 at Satis which this year is October 19th/20th, so I would expect more news by then. What I would say is that the prototype appears to be more than just a simple mock up as it shows some new switch and control designs that I’ve not seen on a Sony camera before. It has also been stated that this new unit is just part of Sony’s 35mm road map so perhaps there will be more than one new camera. As for pricing, well all that Sony will say is “affordable”. My guess is it will be in the XDCAM EX1 price area depending on lens options. If it uses DSLR lenses and can be purchased without a lens, my guess is that it would be cheaper than an EX but more expensive than a Canon 5DMk2, my guess would be £4k.

So what features can we expect to get? The sensor should have large pixels so it should be good in low light and offer high dynamic range. As it has a 35mm sensor I expect it will shoot 24P, 25P, 30P plus I would hope over-cranking at up to 60fps. It would be really nice if it did 1080P60. It should have decent audio controls and it’s going to need a really, really good viewfinder. I would imagine that you will have a number of different lens options via some form of adapter, possibly being supplied with a Sony Alpha lens mount. The prototype was shown with a PL mount lens and very few users will be able to afford to use them, so there will have to be a lower cost option.

These are exciting times. In the next 12 months we will see a huge change in the tools available for video production. The new 35mm and 4/3″ cameras from Sony, Panasonic and Canon will change the way TV is made forever. They won’t be ideal for some applications such as news or run and gun, where you don’t want the focus problems that a big sensor will bring, but for drama, documentary and low budget movies I think we will see a dramayic change in the way things are done.

I’m watching the first episode of the new season of Dr Who on the BBC HD channel and there is a woman wearing a black colored police uniform, except it isn’t quite black. The stab proof vest is very slightly maroon in some scenes. There are black plastic pieces attached to the vest and these are completely black, but in many of the exterior scenes the vest has a distinct red tinge, as does the Dr’s tie. In other scenes it’s completely black. This looks very similar to the near-IR contamination you can get with an EX1. Other than that the pictures look really nice, very high detail, yet with controlled DoF, rich colours and very clean. Anyone know which camera Dr Who is shot with?

UPDATE:

So it’s a Sony F35. Other than what possibly may have been some near IR contamination, I thought these were some of the best HD images I’ve seen on TV. It really looked great. Lets hope that we see more productions using the F35. I did at one point say that the F35 was 2/3″, which of course it is not, it is a 35mm size sensor (Thanks for the correction Dave C). One of the nice things about Dr Who was the way DoF was used. There were many scenes with very deep DoF, loaded with fine detail that looked amazing and there were also scenes where shallow DoF was used to good effect. But what was nice IMHO, was that the producers didn’t go over the top with the DoF, it was never so shallow or so deep that it detracted from the story telling.

Well NAB is just over a week away  (If your going please drop by the Convergent Design booth and say hello). I’m expecting a few surprises as well as some more predictable product launches. Right now, I’m trying to work out where I’m going with my camera kits. I’m traveling more and more and baggage restrictions are getting worse and worse. I’m shooting a lot of 3D as well. Looking in to my crystal ball I see DSLR technology maturing and the issues the current DSLR cameras have being resolved, so some time in the future the value and usefulness of the traditional video camera (as we know it) is going to reduce. The idea of a small camera body with a large sensor that permits the use of the plethora of low cost stills camera lenses is also highly attractive.

So what to do? I currently have a couple of EX’s, a PDW-700 and a 550D as well as minicams and other stuff. I can shot pretty much anything I want with the kit I have, but the lease payments are eating up my profits, after all I can’t use them all at once. Ideally, I would like to have just two cameras (so I can do 3D) that are small and portable, yet with the best quality I can get. I’d really like them to be CCD and with big sensors for shallow DoF, high sensitivity and good latitude. They must meet broadcast HD specs (adding a NanoFlash is acceptable). Hmmm sounds like I might be describing a pair of Scarlet’s, but at the moment they are vapourware, the s35 version is also a bit on the expensive side. These are exciting times, big sensor video cameras are coming to the masses, maybe some clever company will bring out a camera that will work with 35mm photography lenses and then use a windowed part of the sensor to use 2/3″ video lenses, bringing the best of both worlds.

This NAB will be very interesting, the broadcast industry is changing faster now than it has ever changed before.

I have finally found a camera bag that fits my needs (and my PMW-350K)! The Kata TCCT is a clever bag that converts from an airline regulation sized carry-on bag to a full size grab and go camera bag.

Kata TCCT in expanded working mode (I had not put in the stiffener for the pic)

For a couple of years I have been using a conventional carry on case to take my broken down cameras on flights. This is OK, except that once at my destination and with the camera assembled I don’t have a bag for the camera and I have an empty case taking up valuable baggage space. I really could have done with the TCCT in Norway when the rental car company messed up and we only had a tiny car. For a full review of this excellent bag please CLICK HERE.