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I’ve been loaned a PMW-320 to put it through it’s paces. I have not finished my tests yet but one thing that I have noticed is that there is less noise in the pictures from the PMW-320 than from my EX3. I’ve been told that the 320 uses the same sensors as the EX3 and was told that the image quality should be the same. But right now what I am seeing is a cleaner image. This is good news and makes the 320 an interesting proposition. It’s not as clean as the rather remarkable PMW-350, but it appears to me to be an improvement over the EX1/EX3. This is most likely through the use of more advanced noise reduction circuits. The noise levels on the EX1/EX3 have never been a problem for me, but the cleaner the image the more you can do in post production so lower noise is always welcome. I’ll be posting some frame grabs later and a more in depth review.

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.

Front view of beam splitter rig.

I have just finished putting together a new beam splitter 3D rig. This new rig replaces an older one that was less flexible and harder to set up. It is designed to work with an EX1 and EX3 or a pair of EX3. It could also be used with any other cameras of a similar size.

A beam splitter rig uses a mirror that reflects half the incoming light to one camera while the rest of the light passes through to the second camera. The advantage is that in effect the cameras can be mounted very close together optically. If you look carefully at the image on the left you can see that the lenses of the cameras appear to overlap. With the mirror box currently fitted to the rig I can go from zero separation to 110 mm separation (interaxial) just by turning a knob and sliding the top camera from side to side. The mirror box can be quickly and easily exchanged for a larger mirror box for wider lenses or greater separation. I’m currently using an old mirror from an old rig, but I have a new color corrected 50:50 mirror on order that should come this week.

The entire rig can be powered by a single V-Lock battery, the battery helps counterbalance the weight of the lower EX3 and mirror box. It can also be used handheld by adding hand grips to the front mount. On the rear I have a pair of NanoFlashes for improved recording flexibility and better image quality.

The monitor is a rather nice Transvideo Cinemonitor HD 6 with 3D View. I have this on loan and I will be sad to see this go back as it’s really excellent. It’s remarkably bright (it has LED back lighting) and very sharp. It allows 3D monitoring via shutter glasses or anaglyph. It can even flop one of the HDSDI inputs, so even with a mirror rig you can monitor your 3D in real time. It also has built in waveform display.

The rear of Alister's beam splitter rig

The Transvideo 3D monitor makes setting up the rig a breeze. The mirror box has adjustments for skew and tilt and the cameras can be adjusted for toe-in/toe-out.

Mirror rigs are not ideal, as you can see they are large and cumbersome. But for any kind of close up work you need a narrow interaxial, often less than the 65mm of our own eyes. There are very few cameras that can be placed this close together, let alone lenses. For Avatar, James Cameron used some specially modified cameras and lenses that could be mounted very close together, but these kinds of modifications are extremely expensive and beyond the means of many productions, so mirror rigs will be around for some time to come. There biggest problem is the bulk, smaller cameras would allow a smaller rig to be built and perhaps in the future it will be possible to use a pair of video capable DSLR type cameras on a very small and compact rig. This is certainly something I am investigating, but at the moment, as well as the image quality issues it is difficult to get the cameras to run in sync. The XDCAM EX3 can be genlocked, so sync with an EX1 and EX3 or a pair of EX3′s is not an issue.

Alister's new beam splitter 3D rig

I will be running a 3D workshop in Oklahoma City, USA at the end of May and another workshop near London in early June if you are interested in learning how to shoot stereoscopic 3D with both mirror rigs and side by side rigs.

For more on the Transvideo monitor please see my review by clicking here.

PMW-350 Aperture Correction

After completing the multi camera shootout at Visual Impact, one thing was bothering me about the pictures from the PMW-350 and that was the way the specular highlights in the tin foil were artificially enhanced. During the test the camera was set to factory defaults, which IMHO are too sharp, but the foil in particular looked nasty. Since then I have been further refining my paint settings for the 350 and looking at detail and aperture. Today I was replicating the tin foil test and looking at the aperture settings (not the knee aperture) and I noticed that turning aperture on and off had a very pronounced effect on highlights but a much smaller effect elsewhere in the image. Normally I would expect the aperture setting to act as a high frequency boost making subtle textures more or less enhanced, which it does, but the amount of enhancement appears to vary with the brightness of the image with specular highlights getting a really big hit of correction. If you look at the images to the left at the top you have aperture correction on at +99. There are big ugly black lines around the highlights on the foil and the texture of the carpet has been enhanced. To some degree this is the expected behaviour although I am surprised by how thick the edges around the highlights are, this looks more like detail correction (it could be “ringing”). The middle images are aperture off, not zero but actually off and you can see that the edges on the foil have gone and the carpet is no longer enhanced. The bottom picture though with aperture on at -99 though is very interesting as the carpet appears slightly softer than OFF, which is not unexpected while the foils is sharper than OFF and this is not expected. I don’t like this behaviour I’m afraid to say as a typical way to get a filmic look from a video camera is to turn the detail correction off to give a natural picture and then use Aperture correction to boost high frequencies to retain a sharp image. On the PMW-350 you can’t do this as this as a high Aperture setting will give you those nasty edges on highlights. So what can you do? Well the 350′s native, un-enhanced resolution is very high anyway so it doesn’t need a lot of correction or boosting. The default Detail and Aperture settings will give some really nasty highlight edges so you need to back things off. If your going for a filmic look I would turn OFF aperture correction altogether, for video work with pictures that have some subtle enhancement I would use Aperture at around -20, certainly never higher than -15 unless you like black lines around specular highlights.

My current prefered detail, aimed at giving a very slight, not obvious enhancement are are as follows:

Detail Level -12, H-V Ratio +15, Crispening 0, Frequency +30, White Limit +30, Black Limit +40 (all other detail settings at default)

Aperture OFF for filmic look, Aperture -20 for video look.

I have also made some changes to the Matrix settings. I have been finding the pictures from Sony cameras to be a little on the Green/Yellow side so I have tweaked things a little to remove the yellow cast and put in a bit of red, this is a subtle change but really helps with skin tones, stopping on screen talent from looking ill! These settings work in the PMW-350, EX1/3 and PDW-700.

On an EX1/EX3 this works best with the Standard Matrix, On a PMW-350 or PDW-700 you can use it on it’s own or mix it with one of the preset matrices as a modifier. User Matrix On, R-G 0, R-B +5, G-R -6, G-B +8, B-R -15, B-G -9

Have Fun!

Crispening is one of the adjustments you can make in many of Sony’s video cameras that adjusts the way the image is sharpened via the detail correction circuit. On an EX1 or EX3 it is in the Picture Profiles section. If use wisely Crispening can be used to help deal with camera noise by making it less visible, thus giving a cleaner image. Crispening works across the entire luma (brightness) range. It’s really difficult to explain how the level adjustment works, it is a threshold adjustment for the detail circuit, but I’ll have a go anyway.

First off lets consider how the detail circuit works. The camera uses delay circuits to compare how the brightness (luma) levels of adjacent pixels are changing, both from left to right and line by line. If the circuit sees a rapid change from light to dark or dark to light (or light to lighter, dark to darker etc) the circuit regards this as an edge and detail correction is applied by brightening or darkening the transition, exaggerating the edge. This is seen in extreme cases as a black or white halo around edges.

On the EX cameras crispening works by adjusting the threshold at which the light to dark transition between pixels triggers the application of detail correction. So when you set a negative number, say -99 even the slightest luma difference between pixels will have detail correction applied. Set it to +99 and it takes a much greater luma change to trigger the detail circuit.

What you need to understand is that if you set crispening such that the threshold before detail is applied is 100mV (for example) then between 0v (black) and 99mV little to no detail correction will be applied, keeping blacks clean by not applying detail correction to any noise with an amplitude less than 100mV. But if there are subtle textures in the image, going say from 500mV to 599mV (mid tones) then no detail correction will be applied here either, so the image will appear a little softer, only larger luma changes of more than 100mV will have detail correction applied. These small luma changes can be anywhere within the full luma range and it is not confined just to the darker parts of the image.

Raising the crispening level setting to a positive number raises the threshold at which detail is applied to the image, so a high number prevents detail correction from being added to small luma changes. A negative number means that detail correction will be applied to smaller luma changes, this increases the appearance of noise but also makes textures appear sharper.

One thing to consider is that the noise the camera produces is not only in the blacks. If the noise amplitude (level) is for example 5mV, then if you have a subject at 500mV (mid tones) it will still have random 5mV noise added to it. It just tends to be that noise is most visible in the blacks as 5mV of noise on a 5mV (very dark) signal is modulating (varying) the signal by 100% so it’s quite obvious, however 5mV on top of 500mV is only 1% so less obvious, but still there and still visible.

You should remember that the cleaner you can make the recorded image the less stress there is on the codec. This in turn means less mosquito noise and macro blocking giving an image that looks cleaner still and grades better. I struggle to see the difference between crispening at 0 and at +20 in most normally exposed shots, but if I look closely I do see less noise in shadow and low contrast areas. Low contrast areas tend to have little detail anyway, so being able to clean these up a little helps in post production.

Sony have a PDF about it here:
http://www.sony.co.uk/res/attachment…6605183226.pdf

UPDATE: You can download some frame grabs from the shoot-out by clicking here.

I just spent the day shooting the same scene with 6 different file based cameras. I am working with Visual Imapact to produce a series of DVD’s containing sample clips in their native format and file structure from a range of cameras. On the set today I had the following cameras: Sony PDW-700, Sony PMW-350, Sony EX3, Panasonic HPX3700, Panasonic HPX301 and a Panasonic HVX200. We also recorded the output from the PMW-350 on a NanoFlash and this footage will also be available within the DVD set. The idea is to provide people with a way to directly compare the image quality and workflow of all these cameras, in effect, side-by side.

In order to keep things fair each camera was set to it’s factory defaults. Now I know that with careful tweaking all the camera are capable of better pictures, but it was decided the fairest test was to present them in their default settings.

The scene used in the shoot comprised of a colorful Lego train on a small circle of track, some crumpled foil to give bright specular highlights, a chamois leather for natural texture along with a couple of rose blooms. A metal bodied torch and paint brush finished off the still life. In the background there is a sharpness chart and a color chart. All this was then placed on a chroma key green fabric covered table with a chroma key blue back drop.

The scene was shot at 3 different frame sizes in 1080P25, 1080i50 and where available 720P50 and SD. The scene was shot at 0db gain and also at +6db gain. It was exposed using a 50% grey card measured with a Hamlet Microflex scope to ensure matching exposures. A slate was used at the beginning of each shot to identify the camera, the frame rate, aperture and recording mode. The Panasonic P2 cameras were used in both AVC-I modes and DVCPROHD modes. All the 2/3″ cameras used the same Canon HJ14x4.3 lens but I did in addition use the kit lens on the PMW-350 for comparison as well as an SD lens on the PDW-700. The HPX301 and EX3 used their standard lenses.

I’ll be spending the next couple of days checking the footage and compiling the DVD’s, but hope to have the full set of disks available for purchase very soon.

Here is a clip from the Goodwood Revival, shot using an EX3, HXR-MC1 and NanoFLash.

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.

Well not quite right now, but I have been informed by Tiffen that the dealers should have the filters in stock in the UK next week. The price is around £60 GBP so quite reasonable. The filter removes the red cast that certain man made black fabrics can have under some lighting conditions. If you do weddings this should be a must have item. You will need to white balance with the filter in place as it will give a slight green tint if you don’t.

I have been asked to show how I mount my NanoFlash on my EX3 so below are a couple of pictures of the full rig with some details of some of the various items that I use.

1. This is my Petroff 4×4 matte box with bellows hood. I love the old fashioned style bellows lens shade as you can adjust it in and out very quickly to eliminate stray light. A french Flag can be added if desired, but I find in most cases that the bellows shade is fine. Stray light causes reflections both between filters and within the lens, this can reduce contrast in the image so a good lens hood is essential for getting the best pictures. The Matte Box has 2 rotating filter holders. I often use some very gentle blue or grey grads to help with bright skies.

2. The standard EX3 lens. This lens is a remarkably good lens. Keep it between F8 and F2.8 for best results. The sweet spot is F4. Never use the Iris at F16 or F11, your pictures will be soft due to diffraction limiting. This is not a lens fault but something that would happen with any lens and 1/2″ sensors (it’s even worse with smaller sensors). The beauty of the standard EX lens is that it incorporates automatic chromatic aberration correction which means no nasty blue or purple fringes around areas of high contrast.

3. SxS Cards. Even though I was one of the first people to work out how to use low cost SD cards with the fabled Kennsington Adapter I still use SxS cards. The reason is simple: reliability. If you look around the forums you will find lots of people having issues with SD cards. For example a wedding videographer that lost a large part of a service he had shot. If he had used SxS then that just would not have happened. I am a professional and my reputation is vital. That reputation could easily be destroyed if I came back from a shoot with nothing but corrupt data because I had tried to cut corners.

4. Kata Camera Glove. Protects the camera from everyday knocks and bumps as well as unexpected rain or dust.

5. The Cheek Pad. I know many EX3 users don’t fit these. It looks flimsy, but in use it’s strong enough and it really helps to stop the cameras tendency to want to tilt to the left. It makes the camera much more stable and really is worth trying.

6. Convergent Design NanoFlash. This incredible little box allows me to record from the HDSDi output at upto 160Mb/s long Gop. At 100 Mb/s you can’t tell the compressed from the uncompressed. By shooting with this I can grade and color correct my footage, make dubs, go multi generation without seeing any drop in quality. It also means my footage is accepted for HD broadcast by the BBC and the majority of other HD broadcasters. The EX 35Mb footage is good, don’t get me wrong but the 100Mb is sweet. It uses inexpensive Compact Flash cards and by recording to both SxS and the Nano at the same time I can be sure that even if I were to get a card failure I have a backup.

7. IDX V-Lock batteries. One of these will run this rig for around 5 hours. I am also looking at getting some of the Swit EX batteries with the Power-Con/D-Tap out to run the EX and NanoFlash, but by putting the battery out behind the camera the overall balance of the rig is improved. In fact without this larger battery the matte box tends to make it very front heavy.

8. Quick release shoulder pad. This is a home brew affair that incorporates a shoulder pad the V-lock battery adapter and NanoFlash or Radio Mic mount. It can be removed without tools in seconds. Perhaps one day I will get some Zacuto rails or similar, but they are rather expensive and this setup works very well for me.

9. Sony ECM-680S. This is a nice Stereo/Mono switchable gun mic. It is great for capturing nice stereo ambience and effects sound. Flick the switch and it becomes a useful interview mic.

10. DM accessories EX3 reinforcement plate. This is a MUST HAVE item. It provides you with a much stronger tripod fixing with both 1/4″ and 1/2″ threads as well as a host of other threaded holes for various applications. It makes the camera feel so much more solid on a tripod. I really can’t recommend it enough. below this is a cheap, Indian made Matte Box rail kit. It works, but again I could really do with some Zacuto rails or similar.

11. Chamois leather viewfinder cover. Much nicer against your skin than hard rubber. Also absorbs sweat and moisture which helps prevent the viewfinder from fogging. Another option is a small sweat band.