Here’s a quick edit of some of the Aurora footage I managed to grab with the PMW-350 on the 6th of Feb in Karasjok in Northern Norway.
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Multi-Camera Shoot-out Update
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.
Multi Camera Shoot-Out at Visual Impact.
I’m doing a multi camera shoot out at Visual Impact tomorrow in order to put together a DVD of native clips from many of the currently available HD cameras. So far we have the following cameras lined up for the test:
PDW-700, PMW-350, EX3, HPX-301 and HPX3700. Hopefully we will be able to include some JVC’s cameras in a future session. The idea is to compile a DVD of raw footage from all of these cameras under identical lighting situations to enable potential buyers to see for themselves the differences (or not) between the cameras and workflows. It is not going to be a “which is best” review or comparison as all the cameras have strengths and weaknesses. I’ll post details of how to get a copy of the DVD in due course.
Canon To Launch 4:2:2 50Mb/s MXF HD Camcorder!
Canon has been keeping quiet for some time now and there has been lots of speculation about their next video camera, including many that had hoped for a 35mm sized sensor. Well this morning Canon posted a press release on their website. The main and most exciting point is that the camera under development will be full 1920×1080 and it will be 50Mb/s 4:2:2 Mpeg 2 MXF. Now this looks on paper to be an extremely similar format to XDCAM HD422. It would certainly make edit suite integration a lot simpler if the MXF files are the same as the Sony XDAM MXF’s.
Mockups of a camera seen in recent months have shown a handycam style, fixed lens camera with two slots for some type of memory card, which could possibly be express card slots. The mockup lens looks like it might be an EX1 style lens with manual and auto focus and might be big enough to accommodate 1/2? sensors. Is this the camera that the press release refers to, or is there another camera in the pipelines? There is a lot of stuff not mentioned in the press release, like recording media. It says “file based”, this could be solid state or it could be something else, maybe optical disc. Might this be a full size XDCAM HD camcorder from Canon? The release gives no sensor or form factor information which I find a little odd. Having shown mockups of an EX1 sized camera why not a more detailed press release with info on the lens, sensors, recording media etc? (apparently there will be another press release on the 8th of Feb).
Canon make some very good video cameras, I had an XL-H1 and it was a great HDV camcorder. I have no doubt that this new camera will be very good and competitively priced. IF it is the EX1 sized camera and it has 1/2? sensors then this would tick all of the BBC’s boxes for HD. If it’s CCD (which seems likely) it won’t have skew or flash banding. This is a very significant announcement and could push Canon to the front of the Pro Handycam pack. Here is the full press release from the Canon web site.
New Canon MPEG-2 Codec chosen for file-based professional video camcorder promises compatibility with industry-standard editing & processing software
United Kingdom / Republic of Ireland February 2nd 2010 – Canon Inc. today announces the adoption of an MPEG-2 Full HD (4:2:2) file-based recording codec for a new professional video camcorder currently under development. The Canon MPEG-2 codec will enable high-quality imaging and audio performance with up to 50 Mbps data recording and twice the colour data of HDV HDV is a standard for the recording and playback of high definition (1,440 x 1,080 pixels) video and audio on DV-format cassette tapes profile formats. File-based recording helps video operations realise greater efficiencies during post-production processing, making it an ideal format for many industry applications such as news gathering, documentary filmmaking and event videography.
MPEG-2 Full HD compression and 4:2:2 colour sampling?The adoption of MPEG-2 Full HD (MPEG-2 4:2:2 HP@HL compliant) compression enables the recording of 1,920 x 1,080-pixel full high-definition video. Additionally, compared with the 4:2:0 profile format used in HDV and other standards, 4:2:2 colour sampling offers twice the volume of colour data, providing double the level of colour resolution.
Maximum 50 Mbps data recording?With approximately twice the total data volume of HDV, the codec supports higher resolution and increased colour data to enable the recording of high-quality video.
Industry-standard MXF file format (see note (II))?MXF (Material eXchange Format) is a widely supported open source file format for the recording of video, audio and metadata, developed to suit the latest editing systems used by broadcasters.
Canon partners with major editing and processing software?With the adoption of the MPEG-2 Full HD (4:2:2) file-based recording codec, Canon is working in cooperation with Adobe Systems Incorporated, Apple Inc., Avid Technology, Inc. and Grass Valley to ensure compatibility with major editing and processing software programs widely used within the video imaging industry. Additionally, at future industry events Canon intends to demonstrate the overall video-production workflow, from initial video capture to clip-trimming and final editing. Video clips stored in a file-based recording system and industry-standard software applications will be used.
(II) A format for professional digital video and audio media defined by the Society of Motion Picture and Television Engineers (SMPTE)
Notes to editor
Advantages of File-Based Recording
File-based recording enables video and audio data to be managed and stored by file, much in the same way as computer data. It supports efficiency throughout the production process, from initial video capture to final editing through the entire workflow. Additionally, file-based recording provides users with the flexibility to utilise different editing environments and workflow solutions without the restrictions associated with some other video recording formats, helping to reduce investment costs.
PMW-350 or PDW-700, sample clips.
OK, not very scientific I know, but for those that want to see how close the pictures from theses two cameras are I have shot a quick clip with each and put them in a 54mb zip file for download. The PMW-350 clip is a 35Mb/s MP4 and the PDW-700 clip is a 50Mb/s XDCAM MXF.
The cameras were both set up with similar paint settings using Hypergamma 4. The detail is backed off a bit from the factory settings on both and I used the same lens on both cameras which was the Fujinon 16×8 lens that comes with the PMW-350. The clips have not been adjusted in any way other than trimed in length, this is how they look out of the camera.
Both are remarkably similar. I can see that the 350 is more highly saturated and that you can just about make out the difference between 4:2:0 and 4:2:2. The interesting area is how the 350 handles the overexposed sky behind the trees, or rather the way the trees don’t appear to blur into the overexposure as with the PDW-700.
Brewing up a scene file: Black Gamma
In the posts above I looked at how the gamma curves effect the contrast range within the picture and highlight handling. I also noted that while I like the latitude (range) offered by using the Hypergammas that they produce a very flat looking picture. One of the adjustments that you can make to the Gamma curves is the Black Gamma. Adjusting the Black Gamma stretches or compresses the bottom part of the gamma curve, this makes the darker parts of the picture darker (negative setting) or brighter (positive setting). When setting the Black Gamma you will find 4 different ranges to choose from. Low, Low-Mid, Hi-Mid and High. These settings determine the range over which the black gamma works. Low only effects the darkest 10% of the image, L-Mid the bottom 20%(approx), H-Mid the lowest 30%(approx) and Hi the lower 35% (approx). So if you just want to make your deep shadows and blacks darker you would use Low. If you want to make the overall image more contrasty you would use H-Mid or Hi. I like to give my images a bit more impact so I often use H-Mid at -30. If the pictures are to be graded I would not use any negative black gamma.
Brewing up a Scene File for the PMW-350 (and other cameras)
I decided to write a more detailed post to continue the discussions on scene file settings for the PMW-350. This is a work in progress. Some of this may also be of interest to other camera users as I hope to give a basic description of what all the various settings do.
First off let me say that there is no “right way” or “wrong way” to set up a scene file. What works for one person may not be to anothers taste, or suit different applications. For me, my requirements are a neutral look, not over corrected or too vivid, but retaining a pleasing contrast range. I hope, as this thread develops to explain a little bit about each of the settings and what they actually do in the hope that it will make it easy for you to adjust the scene files to suit your own needs. I hope others will jump in with their suggestions too!
So first of all I have been looking at the sharpness of the image. The principle settings that affect this are the Detail and Aperture settings.
Detail enhances rapid transitions from light to dark within the pictures by exaggerating the transition with the addition of a black or white edge. So it only really works on object outlines and larger details (low frequency). The circuitry that determines where these edges are uses an electronic delay to compare adjacent pixels to see whether they are brighter or darker compared to each other. Because of this any rapid movement within the frame stops the circuitry from working. If you have picture with a lot of detail correction and you do a pan for example the image will appear to go soft as soon as the camera moves as the detail circuitry can no longer determine where the edges within the image are and thus applies less detail correction. A good way to visually gauge how much detail a camera is applying to a clip is to look for this. With a good high resolution camera, set up well, it should not be all that obvious, but a low resolution camera that uses lots of detail correction to compensate will exhibit lots of softening on pans.
As well as adjusting the amount of detail correction (Detail Level), you can also adjust the ratio of horizontal and vertical correction, the maximum brightness or darkness of the applied edges (white and black limit). The thickness of the edges (frequency), the minimum contrast change that the correction will be applied to (crispening) and you can tell the camera not to apply detail correction to dark areas (level depend).
The other setting that effects picture sharpness is Aperture. Aperture correction is a high frequency boost circuit, it simply, in effect, enhances transitions from dark to light or light to dark in fine detail and textures such as fabrics, skin, hair, grass etc. It’s operation is not as obvious as “Detail” correction, but if overdone it can make textures sparkle with flashes of white or black, all very un-natural.
An important note about image detail is that if you have too much of it for the given image resolution then you get problems such as aliasing and moire which manifest themselves as rainbows of colour or buzzing, jittering areas in the picture. If you want to know more about this look up Nyquist theory. This is one of the reasons why downconverting HD to SD and getting a good picture can be harder than you might think as you are often starting out with too much detail (but that’s another topic on it’s own).
So… on to the PMW-350. Out of the box it’s really sharp. The camera has full 1920×1080 sensors, so even with all detail correction turned off the image is still pretty sharp. However most viewers are used to seeing picture with some detail correction, so if you turn it all off, to many it looks soft. If you were going for a really filmic look, detail off and aperture off would have to be a serious option. For my customers though a little bit of subtle “zing” seems to be what they like.
I found that these settings worked well for general all-round use.
Detail Level -14?H/V Ratio +20 (helps balance horizontal and vertical resolution)?Frequency +35 (makes the edges thinner, if your doing a lot of SD you may want to go the other way to -50 so that the edges can still be seen in SD)?White Limit +35 (limits brightness of white edges)?Black Limit +30 (limits darkness of black edges)
Aperture -20
If you are doing a lot of grading and work with low key scenes (large dark areas) you can use the level depend and crispening settings to help prevent “detail” being added to any picture noise. This makes any noise less apparent.
A starting point for this would be:
Crispening +35?Level depend +20
For normal light levels these are not needed with the 350 IMHO. If you are shooting with more than +6db gain then raising the level depend to +60 will help with noise.
Brewing up a Scene File: Gamma and Knee
Before anyone complains that I have missed stuff out or that some technical detail is not quite right, one of the things I’m trying to do here is simplify the hows and why’s to try and make it easier for the less technical people out there. Lets face it this is an art form, not a science (well actually a bit of both really).
So what is a gamma curve anyway? Well the good old fashioned cathode ray tube television was a very non-linear device. You put 1 unit of power in and get one unit of light out. You put 2 units in and get 1.5 units out, put 3 in and get 2 out… and so on. So in order to get a natural picture the output of the camera also has to be modified to compensate for this. This compensation is the gamma curve, an artificial modification of the output signal from the camera to make it match TV’s and monitors around the world. See Wikipedia for a fuller explaination: http://en.wikipedia.org/wiki/Gamma_correction
So, all video cameras will have a gamma curve, whether you can adjust it or not is another matter. Certainly most pro level cameras allow you some form of gamma adjustment.
The PMW-350 has 6 standard gamma curves, these are all pretty similar, they have to be otherwise the pictures wouldn’t look right, but small changes in the curve effect the relationship between dark and bright parts of the pictures. Todays modern cameras have a far greater dynamic range (range of dark to bright) than older cameras. This means that the full dynamic range of the sensor no longer fits within the gamma curves used for TV’s and monitors. In broadcast television any signal that goes over 100% gets clipped off and is discarded, so the cameras entire brightness range has to be squeezed into 0 to 100%. The PMW-350 sensors are capable of far more than this (at least 600%) so what can you do?
The older and simpler solution is called the “Knee”. The knee works because in most cases the brightest parts of a scene contains little detail and is generally ignored by our brains. We humans tend to focus on mid-tone faces, animals and plants rather than the bright sky. Because of this you can compress the highlights (bright) parts of the picture quite heavily without it looking hugely un-natural (most of the time at least). What the knee does is takes a standard gamma curve and up near it’s top, bends it over. This has the effect of compressing the brighter parts of the image, squashing a broad range of highlights (clouds for example) into a narrow range of brightness. While this works fairly well, it does tend to look rather “electronic” as the picture is either natural (below the knee) or compressed (above the knee).
The answer to this electronic video look is to replace the hard knee with gentle bend to the gamma curve. This bend starts some way down the gamma curve, very gentle at first but getting harder and harder as you go up the gamma curve. This has the effect of compressing the image gently at first with the compression getting stronger and stronger as you go up the curve. This looks a lot more natural than a hard knee and is far closer to the way film handles highlights. The downside is that because the compression starts earlier a wider tonal range is compressed. This makes the pictures look flat and uninteresting. You have to watch exposure on faces as these can creep into the compressed part of the curve. The plus point is that it’s possible to squeeze large amounts of latitude into the 100% video range. This video can then be worked on in post production by the editor or colorist who can pull out the tonal range that best suits the production.
These compressed gamma curves are given different names on different products. Panasonic call them “Film Rec”, on the EX1 they are “Cinegammas” on the PMW-350 they are “Hypergammas”. The 350 has four Hypergammas. The first is 3250. this takes a brightness range the equivalent to 325% and compresses it down to 100%. HG 4600 takes 460% and squeezes that down to 100%. Both of these Hypergammas are “broadcast safe” and the recordings made with them can be broadcast straight from the camera without any issues. The next Hypergamma is 3259. This takes a 325% range and squeezes this down to a 109% range, likewise 4609 takes 460% down to 109%. But why 109%? well the extra 9% gives you almost 10% more data to work with in post production compared to broadcast safe 100%. It also gives you the peak white level you need for display on the internet. Of course if you are doing a broadcast show you will need to ensure that the video levels in the finished programme don’t exceed 100%.
My preferred gamma is Hypergamma 4 (4609) as this gives the maximum dynamic range and gives a natural look, however the pictures can look a little flat so if I’m going direct from the camera to finished video without grading I use either a standard gamma or use the Black Gamma function to modify the curve. I’ll explain the Black Gamma in my next post.
There are 6 standard gammas to choose from. I like to stick with gamma 5 which is the ITU-709 HD standard gamma. To increase the dynamic range I use the Knee. The default knee point setting is 90, this is a reasonable setting, but if your shooting with clipping set to 100% you are not getting all the cameras latitude (the Knee at 90 works very well with clipping at 108%). Lowering the knee down to 83 gives you almost another stop of latitude, but you have to be careful as skin tones and faces can creep up towards 83%. It’s very noticeable if skin becomes compressed so you need to watch your exposure. This is also true of the Hypergammas and with them you may need to underexpose faces very slightly. The other option is to set the knee point to 88 and then also adjust the knee slope. The slope is the compression amount. A positive value is more compressed, negative less compressed. With the knee at 88 and slope set to +20 you get good latitude, albeit with quite highly compressed highlights.
If you want to play with the gammas and knee and see how they work one method you can use is to use a paint package on your PC (such as photoshop) to create a full screen left to right graduated image going from Black to white. Then shoot this with the camera (slightly out of focus) while making adjustments to the curves or knee and record the results along with a vocal description of each setting. Import the clips into your favorite editing package and use the waveform monitor or scopes you should be able to see a reasonable representation of the shape of the gamma curve and knee.
So my Gamma Choices are:
For material that will be post produced: Hypergamma 4609 (HG4)
For material that will be used straight from the camera: Standard Gamma 5 Knee at 90 with clip at 108% for non broadcast or Knee at 88 with slope +20 with white clip at 100% for direct to broadcast.
PMW-350 Detail Settings
I have finally managed to get my hands on a production PMW-350. I am going to start dialing it in. The first thing to address for me is the over sharpened pictures, so I have been playing with the Paint settings aiming towards a natural, yet sharp look. I have come up with these detail setings. Everything is default except:
Detail Level -16?H/V Ratio +20?Detail Frequency +35?White limit +39?Black Limit +20?Aperture -30
This is still a work in progress.
Next I’m going to start looking at the Gamma curves and Knee. I have a nice Hamlet MicroFlex scope to help with this. Previously I have had to rely on my eye and then check the footage against the scopes in the edit suite, now I can see the waveforms on location. I’ll be writting up both the gamma settings and a microflex review in due course.
PMW-350 Scene Files. Two to get you started.
With the PMW-350 now starting to ship I thought I would dig out the settings I used when I did my 350 review. I created two scene files and the details are as follows:
File One: Aimed at giving high latitude with deep almost crushed blacks and the image well saturated and slightly warmed up.
Detail: ON Aperture: ON Detail Level: -15 Aperture Level: -10 Detail Frequency: +24
Matrix: ON Matrix (User): ON Matrix (Preset): ON Matrix (Prst) Sel: 6
R-G 1, R-B 12, G-R 2, G-B 11, B-R 0, B-G 0
Gamma: ON Gamma Table: STD Gam Table (STD): 5
Black Gamma: ON Black Gamma Range: HIGH Master BLK Gamma -24
Knee: ON Knee Point: 85.2 Knee Slope: -14
White Clip: ON White Clip Level: 109.0 (If will be graded) 104 (if not graded or for broadcast)
Master Black: -2
File Two: Aimed at giving maximum latitude with deep but not crushed blacks and vivid slightly warmed up colours.
Matrix: ON Matrix (User): ON Matrix (Preset): OFF Matrix (Prst) Sel: 1
R-G 8, R-B 10, G-R 0, G-B 15, B-R 5, B-G 6
Gamma: ON Gamma Table: HG Gam Table (HG): 4
Black Gamma: ON Black Gamma Range: H.MID Master BLK Gamma -28
White Clip: ON White Clip Level: 109.0 (If will be graded) 104 (if not graded or for broadcast)
Master Black: -3
Detail: ON Aperture: ON Detail Level: -15 Aperture Level: -10 Detail Frequency: +24
These settings were created on a pre-production PMW-350 so it would be wise to try them and look at them before using them in anger. All other settings are default or 0.