Tag Archives: setup

How to get the best White Balance (Push Auto WB).

Getting a good white balance is critical to getting a great image, especially if you are not going to be color correcting or grading your footage. When shooting traditionally ie – not with log or raw – A common way to set the cameras white balance is to use the one push auto white balance combined with a white target. You point the camera at the white target, then press the WB button (normally found at the front of the camera just under the lens).
The white target needs to occupy a good portion of the shot but it doesn’t have to completely fill the shot. It can be a pretty small area, 30% is normally enough. The key is to make sure that the white or middle grey target is obvious enough and at the right brightness that the camera uses the right part of the image for the white balance. For example, you could have a white card filling 50% of the screen, but there might be a large white car filling the rest of the shot. The camera could be confused by the car if the brightness of the car is closer to the brightness the camera wants than the white/grey card.
The way it normally works is that the camera looks for a uniformly bright part of the image with very little saturation (color) somewhere between 45 and 90IRE. The camera will then assume this area to be the white balance target. The camera then adjusts the gain of the red and blue channels so that the saturation in that part of the image becomes zero and as a result there is no color over the white or grey target.
 
If you fill the frame with your white/grey card then there can be no confusion. But that isn’t always possible or practical as the card needs to be in the scene and under the light you are balancing for rather than just directly in front of the lens. The larger your white or grey card is the more likely it is that you will get a successful and accurate white balance – provided it’s correctly exposed and in the right place.
 
The white target needs to be in reasonable focus as if it is out of focus this will create a blurred edge with color from any background objects blending into the blur. This could upset the white balance as the camera uses an average value for the whole of white area, so any color bleed at the edges due to defocussing may result in a small color offset.
 
You can use a white card or grey card (white paper at a push, but most paper is bleached slightly blue to make it look whiter to our eyes and this will offset the white balance). The best white balance is normally achieved by using a good quality photography grey card. As the grey card will be lower down in the brightness range, if there is any color, it will be more saturated. So when the camera offsets the R and B gain to eliminate the color it will be more accurate.
 
The shiny white plastic cards often sold as white balance cards are often not good choices for white balance. They are too bright and shiny. Any reflections off a glossy white card will seriously degrade the cameras ability to perform an accurate white balance as the highlights will be in the cameras knee or roll-off and as a result have much reduced saturation and also reduced R and B gain, making it harder for the camera to get a good white balance. In addition the plastics used tend to yellow with age, so if you do use a plastic white balance card make sure it isn’t past it’s best.
Don’t try to white balance off clouds or white cars, they tend to introduce offsets into the white balance.
 
Don’t read too much into the Kelvin reading the camera might give. These values are only a guide, different lenses and many other factors will introduce inaccuracies. It is not at all unusual to have two identical cameras give two different Kelvin values even though both are perfectly white balance matched. If you are not sure that your white balance is correct, repeat the process. If you keep getting the same kelvin number it’s likely you are doing it correctly.
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Picture Profiles for the PXW-FS5.

Caption Picture Profiles for the PXW-FS5.
PXW-FS5 Picture Profiles

The Sony PXW-FS5 is a great little camera. It’s a camera I really enjoy shooting with as I can just grab it and go, picking up some great pictures with the minimum of effort. The built in Picture Profiles offer a wide range of different looks that can be quickly selected by pressing the P Profile button and choosing a profile. But one of the best parts is that you can tweak and adjust each profile to suit different shooting applications.

I tend to leave Picture Profile 7 alone. This is the S-Log2/S-Gamut profile that you must use when shooting raw and S-Log2 is my preferred log curve for shooting 8 bit UHD. But that leaves profiles 1 to 6 to play with and adjust, plus profiles 8 and 9 if you don’t use S-Log3. If you want to go back to the factory settings each profile can be reset individually (using “reset” within the profile settings).

Perhaps the two most challenging situations to shoot in are scenes that are high contrast and bright or low light scenes. Often you may encounter both types of scene on the same shoot, so it would be good if the pictures were at least similar. So we don’t want to use totally different color settings. But you can use different gamma settings to help better deal with the differing lighting levels and contrast ranges.

For brighter scenes I am a big fan of Sony’s “Cinegammas”. The Cinegammas differ from the standard gammas in the way they handle highlights. Basic television gamma has a very limited dynamic range, around 6 stops. Then to extend the dynamic range something called a “knee” is added to the top of the gamma curve. The point where the curve transitions from normal gamma to the knee is called the “knee point”. Everything above the knee is is compressed or squeezed. So in effect below the Knee 1 stop  is record with 1 stops worth of data, but above the knee 3 or 4 stops may be recorded in the same space.

cinegammas-1024x768 Picture Profiles for the PXW-FS5.

In practice this means anything brighter than the knee point will have very little contrast, when you have low contrast it is also hard to see any detail. So the highlights in the image look flat, lack texture and detail. If you have bright skin tones up in the knee they just look like blobs of color. Cotton wool clouds come out as white blobs in the sky and it is the knee that is largely responsible for the “video look”.

Sony’s Cinegammas are different. They do not have a knee. Instead of a hard knee point where you switch instantly from not compressed to compressed they have a slow and gradual transition from not compressed to very compressed. This is not unlike the way film behaves and is typically called a “highlight roll-off”. In practice because this transition is gradual it is less obvious. Because it is less obvious you can start the transition lower down the gamma curve which means you have more recording range for the highlights and can therefore increase the captured dynamic range. But to get the best looking recordings you want to keep faces and skin tones below the more aggressive parts of the roll off, so often you need to expose marginally darker than you would with conventional gamma.

For standard gammas it is typical to set the cameras zebras to 70% and have zebras just starting to appear on skin tones. With the Cinegammas I recommend reducing the zebras to 60%. See this article for more info on the correct exposure http://www.xdcam-user.com/2013/07/correct-exposure-levels-with-sony-hypergammas-and-cinegammas/

If you want to use the Cinegammas and are doing anything for broadcast TV that will not be graded and the video levels corrected to the 100% maximum required for broadcast then you should only ever use Cinegamma 2. All the other Cinegammas allow recording up to 109%.

All the Cinegammas record a similar extended dynamic range, Cinegamma 2 will almost always appear a little darker as it’s recording range is shrunk to ensure it does not exceed 100%., but even though it may appear a little darker, the captured dynamic range is the same.

For brighter scenes Cinegamma 1 is my go-to gamma curve on the FS5. It captures a large dynamic range. For darker scenes I will often use Cinegamma 4 as this raises shadows and the mid range. Cinegamma 4 is also useful for shooting back lit scenes.

Cinegamma 3 is a little more contrasty than Cinegamma 1 so if you want a picture with higher contrast this is the curve you should consider.

What about color?

The standard color mode is OK, but I find it a little gaudy. If you want a more film like look then the Cinema mode works quite well to give a more de-saturated look. But my favourite color mode is the Pro color mode. It’s not as vibrant or highly saturated as the standard or ITU709 color modes but it does produce very accurate colors. It’s a bit less green that the standard color mode. If you want a more vibrant image you can increase the saturation, I find Pro Color at +14 saturation gives great color straight out of the camera.

The Color Depth control is a bit of an odd control. It works by targeting a particular color, but instead of increasing/decreasing the saturation of the color it makes the luminance level of objects that are that color brighter or darker. If you make a red car darker in brightness it makes the color appear stronger relative to the brightness. A positive setting makes the luminance darker, so the color appears stronger, a negative setting makes the luminance brighter so the color appears slightly more washed out.

First the standard look (notice the blobby, flat, no texture look to the clouds from the knee):

standard-1024x576 Picture Profiles for the PXW-FS5.
PXW-FS5 Standard Settings

So, here are some suggested settings for different shooting conditions. Remember, you can mix and match the color and gamma settings, so if you like the colors from one profile you can take the color settings and use them with the contrast settings (gamma, black gamma) of another.

1: AC-GPMC – General purpose, medium contrast (good all-round profile).

Gamma: Cine3, Black Gamma Middle -7, Color Mode Pro, Saturation +16 (substitute Cine3 with Cine2 for direct to air broadcast).

ACGPMC-1024x576 Picture Profiles for the PXW-FS5.
Alister’s PXW-FS5 Profile AC-GPMC

2: AC-GPBT – General purpose for bright high contrast scenes.

Gamma: Cine1, Black Gamma Low -3, Color Mode Pro, Saturation +16 (substitute Cine1 with Cine2 for direct to air broadcast).

ACGPBT-1024x576 Picture Profiles for the PXW-FS5.
Alister’s PXW-FS5 Profile AC-GPBT

3: AC-GPGD – General purpose, looks good direct but good if going to be graded (shadows raised to help in grading)

Gamma: Cine1, Black Gamma Low +4, Color Mode Pro, Saturation 0 (substitute Cine1 with Cine2 for direct to air broadcast).

ACGPGD-1024x576 Picture Profiles for the PXW-FS5.
Alister’s PXW-FS5 profile AC-GPGD

4: AC-GPLL – General purpose profile for darker scenes (raised shadows to make grading easier).

Gamma: Cine4, Black Gamma High +7, Color Mode Pro, Saturation +6 (substitute Cine4 with Cine2 for direct to air broadcast).

ACGPLL-1024x576 Picture Profiles for the PXW-FS5.
Alister’s PXW-FS5 Picture Profile AC-GPLL

5: AC-EXLL – For use in very low light levels (is the equivalent to adding +6db gain, does increase noise).

Gamma: ITU709(800), Black Gamma Low +7, Color Mode Pro, Saturation 0.

ACEXLL-1024x576 Picture Profiles for the PXW-FS5.
Alister’s PXW-FS5 Picture Profile for very low light AC-EXLL

6: AC-ASIA1 – Vibrant colors, slight boost to reds/blues.

Gamma: Cine3, Black Gamma Middle -7, Color Mode ITU709, Saturation +10, Color Depth R+5, G-3, B+2, C+1, M0, Y-2.

ACASIA-1024x576 Picture Profiles for the PXW-FS5.
Alister’s PXW-FS5 Picture Profile AC-ASIA1. Vibrant vivid colors.

AC-FILM1 – Film like color and contrast.

Gamma Cine1, Black Gamma Middle -7, Color Mode Cinema, Saturation +8, Phase -3, Color Depth R+4, G-1, B+1, C0, M0, Y-4.

ACFILM-1024x576 Picture Profiles for the PXW-FS5.
Alister’s PXW-FS5 Picture Profile AC-FILM1, a film-like profile.

 

 

The practicalities of fast run and gun shooting with a large sensor camera.

Supercell-panorama-1024x232 The practicalities of fast run and gun shooting with a large sensor camera.Well I’ve just returned home from NAB and a week of Tornado Chasing in the USA. For the Tornado chasing I was shooting in 4K using my Sony F5. I’ve shot run and gun with my F3 and FS700 in the past when shooting air-shows and similar events. But this was very different. Tornado chasing is potentially dangerous. You often only have seconds  to grab a shot which involves leaping out of a car, quickly setting up a tripod and camera and then framing and exposing the shot. You often only have time for one 30 second shot before you have to jump back into the car and move on out ahead of the storm. All of this my be happening in very strong winds and rain. The storms I chased last week had inflow winds rushing into them at 50+ MPH.

The key to shooting any thing fast moving, like this, is having whatever camera kit your using well configured. You need to be able to find the crucial controls for exposure and focus quickly and easily. You need to have a way of measuring and judging exposure and focus accurately. In addition you need a zoom lens that will allow you to get the kinds of shots you need, there’s no time to swap lenses!

For my storm chasing shoot I used the Sony F5 with R5 recorder. This was fitted with a Micron bridge plate as well as a Micron top cheese plate and “Manhandle”. Instead of the Sony viewfinder I used an Alphatron viewfinder as this has a waveform display for exposure. My general purpose lens was a Sigma 18-200mm f3.5-f6.5 stabilised lens with a Canon mount. To control the iris I used a MTF Effect iris control box. For weather protection a CamRade F5/F55 Wetsuit. The tripod I used for this shoot was a Miller 15 head with a set of Carbon Fibre Solo legs.

DSC02074-300x199 The practicalities of fast run and gun shooting with a large sensor camera.
Storm chasing with a PMW-F5

Overall I was pleased with the way this setup worked. The F5’s ergonomics really help as the logical layout makes it simple to use. The 18-200mm lens is OK. I wish it was faster for shooting in low light but for the daytime and dusk shots, f3.5 (at the wide end) is OK. The F5 is so sensitive that it copes well even with this slow lens. The CamRade wetsuit is excellent. Plenty of clear windows so you can see the camera controls and a well tailored yet loose fit that allows you to get easy access to the camera controls. I’ve used Miller Solo legs before and when you need portability they can’t be beaten. The are not quite as stable as twin tube legged tripods, but for this role they are an excellent fit. The Miller 15 head was also just right. Not too big and bulky, not too small. The fluid motion of the head is really smooth.

DSC01122-300x199 The practicalities of fast run and gun shooting with a large sensor camera.
Storm Chasing in the USA with the PMW-F5

So what didn’t work? Well I used the Element Technica Micron bridge plate. I really like the Micron bridge plate as it allows you to re-balance the camera on the tripod very quickly. But it’s not really designed for quick release, it’s a little tricky to line up the bridge plate with the dovetail so I ended up removing and re-fitting the camera via the tripod plate which again is not ideal. The Micron Bridge plate is not really designed for this type of application, when I go back storm chasing in May I’ll be using a  baseplate that locks into a VCT-14 quick release plate, not sure which one yet, so I have some investigating to do.  The VCT-14 is not nearly as stable or as solid as the Micron, but for this application speed is of the essence and I’m prepared to sacrifice a little bit of stability. The Micron bridge plate is better suited to film style shooting and in that role is fantastic, it’s just not the right tool for this job.

F5-with-rainbow-300x199 The practicalities of fast run and gun shooting with a large sensor camera.
Rainbow under a severe thunderstorm.

The MTF-Effect unit is needed to control the aperture of the Canon mount lens, it also powers the optical image stabiliser. But it’s a large square box. I had it mounted on the top of the camera, not in the best place. I need to look at where to mount the box. I’m actually considering re-housing the unit in a custom made hand grip so I can use it to hold the camera with my left hand and have iris control via a thumbwheel. I also want to power it from one of the camera’s auxiliary outputs rather than using the AA batteries internally. The other option is the more expensive Optitek lens mount which I’m hoping to try out soon.  I’m also getting a different lens. The Sigma was fine, but I’m going to get a Sigma 18-250mm (15x) f3.5-f6.5 for a bit more telephoto reach. The other option I could have used is my MTF B4 adapter and a 2/3″ broadcast zoom, but for 4K the Tamron will have better resolution than an HD lens. If I was just shooting HD then the broadcast lens would probably be the best option. After dark I swapped to my Sigma 24-70mm f2.8 for general purpose shooting and this worked well in low light but with the loss of telephoto reach, I need to look into a fast long lens but these tend to be expensive. If you have deep enough pockets the lens to get would probably be the Fujinon Cabrio 19-90 T2.9, but sadly at the moment my budget is blown and my pockets are just not that deep. The Cabrio is very similar to an ENG broadcast lens in that it has a servo zoom, but it’s PL mount and very high resolution. Another lens option would be the Canon CN-E30-105mm T2.8, but overall there isn’t a great deal of choice when it comes down to getting a big zoom range and large aperture at the same time, in a hand-held package. If I was working with a full crew then I would consider using a much larger lens like the Arri Alura 18-80 or Angenieux Optimo 24-290, but then this is no longer what I would consider run and gun and would require an assistant to set up the tripod while I bring out the camera.

LP-storm2-300x168 The practicalities of fast run and gun shooting with a large sensor camera.
A Supercell thunderstorm looking like a flying saucer.

From an operating point of view one thing I had to do was to keep reminding myself to double check focus. If you think focus is critical in HD, then it’s super critical for 4K. Thunderstorms are horrid things to try and focus on as they are low contrast and soft looking. I had to use a lot of peaking as well as the 1:1 pixel function of the Alphatron viewfinder, one of the neat things about the Alphatron is that peaking continues to work even in the 1:1 zoom mode. As I was shooting raw and using the cameras Cine EI mode to make exposure simpler I turned on the Look Up Tables on the HDSDI outputs and used the P1 LUT. I then exposed using the waveform monitor keeping my highlights (for example the brighter clouds) at or lower than 100%. On checking the raw footage back this looks to have worked well. Quite a few shots needed grading down by 1 to 1.5 stops, but this is not an issue as there is so much dynamic range that the highlights are still fine and you get a cleaner, less noisy image. When shooting raw with the F5 and F55 cameras I’d rather grade down than up. These cameras behave much more like  film cameras due to the massive dynamic range and raw recording, so a little bit of overexposure doesn’t hurt the images as it would when shooting with standard gammas or even log. Grading down (bringing levels down) results in lower noise and a cleaner image.

chase3-300x168 The practicalities of fast run and gun shooting with a large sensor camera.
Frame grab from the F5 of a Supercell storm with a grey funnel cloud beneath.

So you can run and gun in an intense fast moving environment with a large sensor camera. It’s not as easy as with a 2/3″ or 1/2″ camera. You have to take a little more time double checking your focus. The F5 is so sensitive that using a F3.5-F6.5 lens is not a huge  problem. A typical 1/2″ camera (EX1, PMW-200) is rated at about 300 ISO and has an f1.8 lens. The F5 in Cine EI mode is 2000 ISO, almost 3 stops more sensitive. So when you put an f3.5 lens on, the F5 ends up performing better in low light, even at f6.5 it’s only effectively one stop less sensitive. For this kind of subject matter you don’t want to be at f1.8 – f2.8 with a super 35mm sensor anyway as the storm scenes and shots involved work better with a deep focus range rather than a shallow one.

Having watched the footage from the shoot back in HD on a large screen monitor I am delighted with the quality of the footage. Even in HD it has better clarity than I have seen in any of my previous storm footage. This is I believe down to the use of a 4K sensor and the very low noise levels. I’d love to see the 4K material on a 4K monitor. It certainly looks good on my Mac’s retina display. Hopefully I’ll get back out on the plains and prairies of Tornado Alley later in May for some more storm chasing. Anyone want to join me?

 

Picture Profiles to match PMW-F3 and NEX-FS700

IMPORTANT PLEASE ENSURE YOU USE THE REVISED SETTINGS UPDATED ON 24th  JULY.

After my recent side by side look at the F3 and FS700 and seeing how different the two cameras look, I decided to try to match them a bit better. There will be many shoots where I will use them both together so getting them to look the same is important. I thought this would be a relatively straight forward task, simply dial in the FS700 to match the F3.

Well it wasn’t simple and it ended up taking me several hours to get to the point where I couldn’t get them any closer. The main issues are that the F3, like most of the XDCAM cameras has a yellow colour cast that’s hard to completely remove and the FS700 has quite a blue image and only very limited matrix controls. Initially I started to try to match the FS700 to a standard F3. While I could get the FS700 closer to the F3, I just couldn’t get a near match let alone a complete match. So back to the drawing board.

For my second attempt I decided first to work on getting rid of the yellow/orange cast to the F3 pictures by adjusting the F3’s matrix, at the same time creating a neutral look picture profile with good dynamic range, but one that could be used without grading. This took some extensive matrix tweaks. You will find the full details of my new “STD-REAL” picture profile in the forum by clicking here.

So once I had a neutral starting point on the F3 I then turned to the FS700 which I think is very blue. The matrix settings on the FS700 are quite limited so I wasn’t able to get an exact match to the F3, however the setting I came up with get them close enough for most jobs, it’s not perfect but it will do. I’m quite happy with my new FS700 settings and I think with this profile it produces a very nice image. You can find the full profile settings in the forum by clicking here. Remember you need to use the matching F3 profile in the F3 for the best match. If you want the maximum dynamic range then instead of Cinegamma 1 you should use Cinegamma 4 with the black gamma set to zero. My STD REAL profile for the FS700 is closer to a standard F3 than the default FS700 settings.

Calibrating your viewfinder or LCD.

smpte-arib-bars-sample Calibrating your viewfinder or LCD.One of the most important things to do before you shoot anything is to make sure that any monitors, viewfinders or LCD panels are accurately calibrated. The majority of modern HD cameras have built in colour bars and these are ideal for checking your monitor. On most Sony cameras you have SMPTE ARIB colour bars like the ones in the image here. Note that I have raised the black level in the image so that you can see some of the key features more clearly. If your using a LCD or OLED monitor connected via HDSDI or HDMI then the main adjustments you will have are for Contrast, Brightness and Saturation.

First set up the monitor or viewfinder so that the 100% white square is shown as peak white on the monitor. This is done by increasing the contrast control until the white box stops getting brighter on the screen. Once it reaches maximum brightness, back the contrast level down until you can just perceive the tiniest of brightness changes on the screen.

Once this is set you now use the pluge bars to set up the black level. The pluge bars are the narrow near black bars that I’ve marked as -2% +2% and +4% in the picture they are each separated by black. The -2% bar is blacker than black so we should not be able to see this. Using the brightness control adjust the screen so that you can’t see the -2% bar but can just see the +2% bar. The 4% bar should also be visible separated from the 2% bar by black.

Color is harder to set accurately. Looking at the bars, the main upper bars are 75% bars so these are fully saturated, but only at 75% luma. The 4 coloured boxes, 2 on each side, two thirds of the way down the pattern are 100% fully saturated boxes. Using the outer 100% boxes increase the saturation or colour level until the color vibrance of the outer boxes stops increasing, then back the level down again until you just perceive the color decreasing. I find this easiest to see with the blue box.

Now you should have good, well saturated looking bars on you monitor or LCD and provided it is of reasonable quality it should be calibrated adequately well for judging exposure.

I find that on an EX or F3 the LCD panel ends up with the contrast at zero, colour at zero and brightness at about +28 on most cameras.

XDCAM Picture Profiles and setups, also C300 coming soon.

I’ve added a new section in the xdcam-user.com forum for listing details of my various picture profiles. You will need to be a registered forum member to view or comment, but registration is free. I hope to add many profiles to this forum over the coming weeks for many of the XDCAM cameras as well as the new Canon C300 once I start to get that dialled in. I’ve started with my EX S-Log style gamma curve.

http://www.xdcam-user.com/forum3/viewtopic.php?f=41&t=194&sid=c233ea884673388efe1e1af8c2ef84c7

EX1 and EX3 Picture Profiles.

These are the picture profiles that I am currently tending to favour for the EX1, EX1R and EX3. Please remember that picture profiles are entirely subjective. These settings work for me, that doesn’t mean they are perfect or for everyone. I like the images the cameras produce when I use these profiles. Please feel free to adapt them or modify them any way you choose. They work on any of the current EX cameras.

Vivid – Designed to help match the EX to a PDW-700. Gives vivid colours with a small shift away from yellow.

Matrix – Cinema, Matrix Level +60

R-G +8,  R-B +10,  G-R 0,  G-B +15,  B-R +5,  B-G +6

Detail Level -10 Frequency +20, Crispening -40 (if using gain use crispening +14)

Gamma Cinegamma 1

Black level -3, Black Gamma -35

Low Key Saturation -10

Natural C4 – Designed to give a neutral, natural looking image.

Matrix – Cinema, Matrix Level +35

Detail level -7, Frequency +30, Crispening -40 (if using gain use crispening +20)

Black Level -3, Low key Saturation -15

AC Punch – Gives a very high contrast, bold look.

Matric – Cinema, level +40

Gamma Standard 2, Knee level 80, Slope 0

R-G 0,  R-B +1,  G-R +12,  G-B +2,  B-R +11,  B-G 0

Detail Level -10, Frequency +30, Crispening -45

Black Level -4, Black Gamma -20.

AC Good to Grade – a general purpose setup to give good grading possibilities.

Matrix – Cinema, Level +25

Gamma Cinegamma 1 (Do not use -3db gain)

Detail Level -7, Frequency +45, Crispening -45 (use +35 if using gain)

Black Level -3.

AC-SD Camera look. To mimic an older SD camcorder based on a DSR400, good for HD to SD conversion.

Matrix – Cinema, Level +15

Detail Level +20, Detail Frequency -35, White Limit +35, Black limit +45

Knee, Manual, Level 90, Slope 0.

Gamma Standard 2, Gamma Level +5

Black Gamma -10

Black Level -10

 

 

Enjoy! Any feedback or suggestions welcome. Let me know of any profiles that you come up with that may be of interest to others.

 

What is “Crispening” and how does it effect the picture?

What is “Crispening” and how does it effect the picture?

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

Stetting up video cameras without charts.

There is far too much emphasis on color charts and 100% one to one – set it up with a scope settings. Very often a 100% accurate one to one response won’t look right as the video gamut is smaller and lopsided than that of the human eye so a small amount of skewing of the color gamut can often help produce a picture that visually looks more natural. One of the very best ways to set up a camera is to use a high quality color photograph of a known scene. Shoot the photograph and look at the picture on a monitor and adjust until it looks right. This will give a more natural looking image than aligning with charts and scopes and is a technique that has been used since the very beginnings of color television. I have a scene that contains vibrant colored cars, green fields and trees, buildings and blue sky. I have a dozen large copies of this picture and use it whenever I am making camera adjustments to make sure my pictures still look natural. Of course scopes should still be used if you are making any extreme settings to ensure your images are still legal, but at the end of the day what you are after is an image that looks right too you (or the producer) and whoever else will view your material, not what looks right according to a chart and a scope.

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.