General Specialist

2011-01-27

Show Reel 2011 Posted



A quick collection of some of my broadcast work for SVT, including motion graphics, design, 3D, time-lapse photography, set design, virtual sets, visual effects and more. You can view it in full SD resolution on Vimeo.


- Jonas

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2010-04-10

See What I Find at NAB 2010




I'm at the NAB 2010 show all week, and want to share what I find. Head over to http://generalspecialist.posterous.com/ where I'll post everything that's worth seeing!

PS. If you're at NAB, give me a call at +46-733-970000 or check my Twitter feeds at @hummelstrand and @CasparCG

- Jonas

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Just Released: Free and Open Source Broadcast Graphics Server

Free and Open SourceWe’ve finally released the new version 1.8.0b4 of the CasparCG system, a broadcast graphics system that plays QuickTime and Flash out to SDI, HD-SDI, HDMI and DVI.
Download installers, source code and tools from http://casparcg.com/

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2008-12-11

RED Finally Cuts in Adobe Apps


While RED has published a picture of the Premiere Pro 1.0 box on their RED Adobe CS4 Installer (beta) page, you'll actually need the newly released version 4.0.1 of Premiere Pro CS4 and version 9.0.1 of After Effects CS4.

The system requirements aren't exactly designed for the famed "soccer mom's" of this world; you'll need to have a 3.0 GHz quad-core system, at least 8 GB of RAM and a 64-bit OS such as OS X or Vista 64 if you want to work comfortably, but using lower resolutions with lesser machines will work as well.

Dave Helmly has posted a video workflow (but could someone please help the guy with the design?)

- Jonas

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2008-12-04

RED's Latest Line-up

The December 3rd updates to RED's earlier announcements seem to be moving in the right direction. However, I can't really figure out if we will be able to get a 2/3-inch Cinema Scarlet sensor with interchangeable lens mounts.
If we can mount 3rd-party lenses to it, with a REDhandle, a viewfinder (BombEVF?) and a recording module the price would presumably be in the vicinity of the $3,750 of the 2/3-inch 8X Fixed Zoom complete kit.

- Jonas

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2008-11-14

Why the RED cameras won't be seen at pool parties

If RED was aiming their new Scarlet to be a "DSLR killer," they missed the mark, unfortunately.

I love what RED is doing to the dinosaurs of the camera business, but I was hoping that a Scarlet would replace my prosumer gear and give me new possibilities. Unless the Scarlet with the fixed lens is dirt-cheap I don't see me getting it.

Instead RED's proposed system may well be a revolution for motion camera design principles with the sensor being decoupled from the rest of the gear, but this current design won't mean anything for me based on these factors:
  1. Stills resolution
    For still images the 2/3" Scarlet's resolution is just 4.9 mega-pixels where at least 8 MP or more was needed to become a usable alternative to any cheap DSLR. You need to go up to the S35 sensor to get 13.8 MP.
  2. Movie resolution
    No doubt this is where all RED systems excel, and the 2/3" sensor's 3K sounds like a sweet spot where the data rate is still manageable while you will still have the ability to crop or down-sample to HD / 2K. However, I'm pretty happy to get 1080p out of my cheap rig or from a Nikon D90 or a Canon EOS 5D Mark II (which are just the first versions of what will surely become standard features of traditional DSLRs.)
  3. Frame rate
    The great 120 fps frame rate available in the 2/3" sensor drops down to a mere 30 fps in the other Scarlet sensors (unless you crop in on the sensor and loose resolution and DOF,) which is a bit of a disappointment. Being able to over-crank to get beautiful slow-mo has always been a dream of mine...
  4. Lenses
    You also need to go up to the S35-sized sensor to be able to attach readily available still camera lenses from Nikon and Canon, which suddenly brings us to the next point:
  5. Price
    Just the S35 sensor and mount for still lenses bring the price up to $7,000, without a viewfinder or any accessories. That's a far cry from something that a prosumer could justify spending on a camera body, considering Canon's and Nikon's bodies which go for under $2,500. If you get the 2/3" sensor you need to get new lenses with special mounts.
  6. Shallow depth-of-field
    The 2/3" sensor is so small (see Stu Maschwitz's sensor cheat sheet) that you won't get the cinematic shallow depth-of-field and bokeh that we all love, without putting a DOF adaptor and additional lenses in front of the 2/3" Scarlet. A super-16-sized sensor is way better most current video cameras (many features have been shot on super-16,) but it's not comparable with the size and look of a DSLR, even those with APS-C-sized sensors like the Canon 30D.
I was hoping for "3K for $3K": a camera body that would do 2K or more at at least 75 fps with a still camera lens mount and shallow depth-of-field-look, and at least same stills resolution that my old Canon 30D had. I guess I'll have to wait another couple of years...

- Jonas

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2008-10-09

Learn VFX from the Masters of the Universe


The world's best supervisors including John Knoll, Scott Squires, John Dykstra, Pablo Helman, Dennis Murren, Mike Fink, Ken Ralson and Kim Libreri are part of a course in the new term at fxphd.com. Imagine learning stuff from the people behind such milestones as Close Encounters of the Third Kind, Star Wars I to VI, Wargames, Back to the Future, The Abyss, Indiana Jones, Terminator 2 & 3, The Matrix, Pirates of the Caribbean and many more of the films that have shaped the last decades.


You already know how much I can recommend fxphd, and the new term is even better than the last one. Make sure you look at the overview movie.

Here's a complete list of available courses. The term starts on October 13 2008, but you can join later and have access to all the classes you've signed up for.

I've been swamped with work, so I still have a couple of courses left from the last term to watch (a tip: convert the classes so you can watch them on a portable media player of your choice; I watch classes in bed while waiting for the kids to fall asleep.)

This new term I'll be taking the DIT course, the new RED course and either Mark Christiansen's AE course or Tim Clapham's AE+C4D course. I wish I had time to dig into the Fusion course as well, but we'll see how it goes.


Oh, if you enter humlan in the Referring Member field on the signup page, I'll get an extra class, which would be really nice. Thanks in advance!

- Jonas

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2008-10-08

Watch and Embed YouTube Clips in High Quality

The term "High Quality" has to be taken with a bucket of salt when we're talking about YouTube, but there's an easy way to at least lessen the compression artifacts, which is especially useful for full-screen viewing. Even a lot of clips that don't have the "Watch in High Quality" link on the page actually exists in a less compressed version.

If you are watching the clip at YouTube.com, just add &fmt=18 at the end of the URL. The easiest way to do this is the create a bookmark in your browser's toolbar. Just bookmark any site and then replace the URL of the bookmark's Location with this simple JavaScript: javascript:window.location+="&fmt=18";
Every time you're at YouTube you can just click the bookmark to see the clip with less compression (if it's available, otherwise the standard clip will play.)

See the difference for yourself:


If you embed videos, you can do the same thing and even embed a larger version, but you have to append &ap=%2526fmt%3D18 to both URL's in the code, plus change the sizes in both places to 480 by 360.





You can also watch YouTube videos with QuickTime embedded player if you'd like, and easily download the clips (if you have QuickTime Player Pro.)


- Jonas

Tip of the hat to My Digital Life and Tobias Lind.

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2008-08-29

ProRes 422 Codec Finally Cross-platform (Sorta...)

Before you get all excited about the Apple ProRes QuickTime Decoder 1.0 for Windows, let's remember that you can only render to ProRes 422 if you're on a Mac and have Final Cut Studio 2 installed. If you don't you'll be in the same boat as the Windows users and will need to install the Apple ProRes QuickTime Decoder 1.0 for Mac.

So, for true cross-platform goodness you'll still be better off with the free (and in size and quality similar or better) Avid DNxHD codec that also supports an alpha channel.

ProRes 422 White Paper

- Jonas

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2008-08-04

Building a Pro Camera Crane / Jib, part 1

I was once told that my favorite interest seemed to be collecting hobbies. That may be truer than I'd like to admit, and for the last six months I've added yet a new project to all my previous (unfinished) tinkerings.

I have a Basic Stamp micro-controller and USB programming board left over from another project that I never finished. One day I realized that a fun use for it would be to build a joystick-controlled pan/tilt camera head that could be placed on the end of a camera crane.

After 30 minutes with a search engine I realized that buying a ready-made crane was out of the question, as the ones I found cost several thousand dollars. Working at a TV broadcaster I have first-hand access to professional jibs and saw that they weren't as mechanically complicated as I had initially thought. I imagined the hard part would be controlling the camera head with a joystick. As the build have progressed I have come to understand that I had seriously underestimated the amount of mechanical work required.

My initial plan was to built a jib with a total length of 3 meter, based on that I found two light and sturdy metallic pipes (25 mm in diameter) in a local hardware store. These would be used as a parallelogram so that the camera head would always be vertical no matter how the jib was raised or lowered. With an arm of that length it would also be easy to fit the jib inside a car.

As the project has progressed I've abandoned these pipes for two reasons. Firstly I've found it hard to fasten the six ball-bearings to these pipes, since they aren't very sturdy and I wouldn't be able to make holes in them without weakening them too much. And secondly, I got megalomania and realized I wanted a longer arm that could still be stuffed into a car, so I decided to abandon the cheap pipes and go with two 3 meter long pieces of rectangular aluminum tube that could be assembled into a 5 meter crane. An added bonus is that the length of the arm can be shortened if necessary.

Using a single arm means that I need to use two pulleys with a wire between them. One pulley will be fastened to the camera head and the other to the tripod mount.

Without a sturdy tripod as a base, the jib would become wobbly and unstable. Luckily I found a great Manfrotto tripod with a fluid video head and detachable dolly wheels on Swedish ebay. You can't complain about the price: $200 including shipping!

To attach the arm to the tripod I've bought a heavy construction bracket used for securing wooden beams. All I had to do was to chop off the protruding flanges and drill a hole for the tripod mounting screw. I'll even be able to use the pre-drilled holes to fasten the axle!

The controller is housed in the clear acrylic case from an iPod Shuffle and is made up of a 9V battery, a Basic Stamp BS2p24 and a Pololu DC Motor Controller. Power to the motors come from an external 6V lead-acid battery that will be used as part of the counter-weight on the arm. The joystick is from a Sony PlayStation 2 and I'm using three potentiometers that will be used as separate pan and tilt speed adjustments plus a zero-point sensitivity adjustment. The code is still pretty rough, but I've added a routine that sets the zero-point of the joystick at boot time. I'll publish the source-code when everything is working, if anyone's interested.

As a camera I'm using my Canon HV-20 with a RedRock Micro M2 lens adapter with a used follow-focus (thanks to ebay again!) Unfortunately the HV-20 doesn't have a LANC port so I'm using a 5 meter long optical fiber to send the IR remote signal from the back of the jib. A bit of a hack, but this is a rebel-style jib after all!

Yes, I know that with only one joystick I don't yet have focus control, but based on previous experience I've chosen to complete version 1.0 before adding any more features. The motor controller can only be connected to two motors, but with my follow-focus I can easily attach a servo to the gear and control that directly from the Basic Stamp.


- So what will it be used for? you ask. Well, now we get into serious denial-territory. I've tried to justify the time and money spent so far with being able to sell really cool shots at iStockPhoto from our upcoming trip to the Norwegian coast , but lately I've come to terms with the fact that I just need the challenge.


I'll keep posting with more pictures as I get closer to final assembly!


- Jonas

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2008-07-22

Even More Great VFX Courses

I've been on a long vacation, so I haven't had a chance to write about the new term. I won't bore regular readers who already know how much I can recommend fxphd.

Here's a complete list of available courses. The term started on July 14 2008, but you can join later and have access to all the classes you've signed up for.

If you want to know more about fxphd, take a look at the fxphd Tour Movie. There's also a great FAQ.

I think I'll choose AFX302 - After Effects Masters, C4D202 - Cinema4D and After Effects in Production and DRK301 - VFX and Indie Films.

Oh, if you enter humlan in the Referring Member field on the signup page, I'll get an extra class, which would be really nice. Thanks in advance!

- Jonas

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2008-04-12

What happens in Vegas doesn't stay there

Stuck at home? Me too...

Here's how to keep tabs on NAB. I'll keep on updating the links as we go...




Basically, if you want the latest as it happens, get a Twitter.com account and follow the people below!
If you are actually at NAB, the nice people at fxguide.com has written an fxguided Tour: Getting the Most Out of NAB

Oh, if someone could please record this key-note, I'd be a happy camper.

What sites did I miss? Write a comment and I'll add them...

- Jonas (also on Twitter since today)

Image by Clinton Steeds

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2008-04-09

Don't Miss the New Term at fxphd.com

Regular readers know I'm a big fan of fxphd.com and that you can't get any more current and professional training even for ten times the price. I've been a member from the start, and the things I've picked up from the past seven terms come in useful every day in my work.

I'm hoping to shoot a documentary in the fall, and can with confidence say "I really think we should rent a Red One for this shoot" based on that I know I have both fxphd's training and forum discussions to lean on for figuring out the workflow. Priceless...

Last term Tim Clapham held a great course on motion graphics in After Effects, and this term he's in charge of a Cinema 4D course. And the creator of 250 HD effects shots in 5 months holds an After Effects course.

I really enjoyed the Photography for VFX course last term which is repeated this term, and I am happy to see a SynthEyes course that I will definitely take.

Here's a complete list of available courses. The term starts on April 14 2008, but you can join later and have access to all the classes you've signed up for.

If you want to know more about fxphd, take a look at the fxphd Tour Movie. There's also a great FAQ and the Orientation Week movie (torrent link) that covers all the upcoming classes.

Oh, if you enter humlan in the Referring Member field on the signup page, I'll get an extra class, which would be really nice. Thanks in advance!

- Jonas

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2008-02-07

QuickTime 7.4.1 Fixes Rendering Bug

Those who were too fast to upgrade to QuickTime 7.4 were bitten by rendering problems, not only in After Effects, but also in RED and even Final Cut Pro. Apple just posted a patch that is designed specifically to fix these issues:
However, I'll still stay on QuickTime 7.3 (I even have a machine on 7.1.3.) I mean; who wants to find out what other surprises Apple has in store for us?

Also, don't miss John Montgomery's article Pro Living in a Consumer QuickTime World.

- Jonas

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2008-01-11

30 Courses to Die For

I've been meaning to post about great training resources for my beloved After Effects, but here's something even better; training for the entire video / animation / graphics / broadcasting / film business.

Regular readers know how I'm a big fan of fxphd.com and that you can't get any more current and professional training even for ten times the price of one term. I've been a member from the start, and believe me; you won't get as much value for your money anywhere else!

You have 30 courses to choose from, ranging from motion graphics in AE with Tim Clapham and typography with Frank Jonen, to RED production and 3D tracking.

Here's a complete list of available courses. The term starts on January 14, 2008, but you can join later and have access to all the classes you've signed up for.

If you want to know more about fxphd, take a look at the fxphd Tour Movie and the Orientation Week movie (torrent link) that covers all the upcoming classes. There's also a great FAQ.

Oh, if you enter humlan in the Referring Member field on the signup page, I'll get an extra class, which would be really nice. Thanks in advance!

- Jonas

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2008-01-10

Choosing a Professional Mic

I'm no audio guy, but I am a geek fanboy, so I just couldn't resist the temptation to link this thorough review on how to choose a mic. It even has has sound samples and cool looking graphs for all the tested mics. Respect!



- Jonas

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If You Built a TV Studio Today, What Would You Build?

I've spent the last few years around TV studios that have slowly been upgraded to handle new additions like 16:9, overlapping projectors, animated LED lighting. In the good-old tradition of public service, everything installed has been proprietary and expensive broadcast equipment.

This slow update-cycle means that older equipment is moved to shows deemed less important. I'm currently re-rendering a title sequence I did four months ago for a show that was shot in 4:3 since their old cameras didn't have a widescreen option. This season they are changing to 16:9...

That's why it's so interesting to see a behind-the-scenes look at how Revision3 is building a studio using cheaper equipment, based on the production principles of today, rather than yesterday. So much has happened in post-production that seemed impossible just a few years ago, and it's inspiring to not have to fight old broadcast engineers that want to spend great wads of cash on dinosaur stuff.
I love how the studio engineer gets all worked up over all the equipment.
"I love patch-bays!"




PS. There's a HD QuickTime available if you want to get motion-sickness from the really bad camera handling.
"It aint't rebel if it ain't shaky..."


- Jonas

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2007-10-02

Best VFX, Graphics and Animation Training Starts New Term

So you think you already know everything you need to do your work? Think again...

fxphd.com has been a big success and when it now enters the fifth term of training, there's even more cutting-edge courses for anyone in the video / animation / graphics / broadcasting / film business. I've been a member from the start, and believe me; you won't get as much value for your money anywhere else!

As an example: last term we got an hours worth of vfx breakdown of the Pirates of the Caribbean by the legendary John Knoll himself. Priceless...

You can join anytime during the term (it starts on October 8th) and this time around you can get both advanced courses by After Effects gurus such as Mark Christiansen (blog / book) and Stu Maschwitz (blog / book) as well as exclusive training in the RED production and workflow.
Here's a complete list of available courses.

If you want to know more about fxphd, take a look at the fxphd Tour Movie

UPDATE: Here's a torrent link to the brand new Orientation Week movie that covers all the upcoming classes.

Oh, if you enter humlan in the Referring Member field on the signup page, I'll get an extra class, which would be really nice. Thanks in advance!

One last tip: don't miss the HD versions of the excellent fxguidetv from the same guys that bring you fxphd!

- Jonas

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2007-09-08

P2/MXF Supported in New Premiere Pro CS3 Patch

The next patch to Premiere Pro CS3 (3.1) will import and output P2 media and MXF files natively without transcoding, rewrapping or conforming.

Update Oct 18: The 3.1 patch is now available via Adobe Updater (choose Update from the Help menu inside any Adobe CS3 application.)

Also, Dave Helmly from Adobe has put together a video demo of Premiere Pro 3.1.

Update Oct 24: There's more info on P2 workflow in the LiveDocs:
Import assets in Panasonic P2 format
About spanned clips from Panasonic P2 media
Export to Panasonic P2 format

- Jonas

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2007-08-26

Eleven Ways to Play Back Your Renderings Without Paying $5,400

1. One of the cheapest ways to play back a sequence of frames or videos is by using QuickTime Pro ($29, OS X & Win.) However, QuickTime Player's RAM caching isn't exactly stellar so expect to get a lot of stuttering. Also, it's supported file formats is limited and you can only see certain channels such as the alpha. On the plus-side is the number of conversions that you can easily do directly from player.






2. If you add $249 you can get the GlueTools CineonDPX Pro components for QuickTime on OS X, which adds nice stuff like timecode, anamorphic correction and 16-bit support.




3. At a cheaper $99 you'll find the beta version of DrasticPreview (Windows only) which also supports Cineon files, among other features. Unfortunately it doesn't support OpenEXR sequences.






4. Another Windows-only software is tv-player ($139) which has some GPU-accelerated functions. A note-worthy feature is realtime field-swapping and an RGB histogram.





5. The current version of Tweak Software's RV ($299) runs on Linux and non-Intel Macs , but the new version with both Windows and Intel-Mac support was shown at Sigraph 2007. Like some of the others, RV can handle HDR images and it also has EDL support.





6. FrameCycler Professional used to cost thousands of dollars, but nowadays there's a version for $299 available for OS X, Linus and Windows.


7. Of course, if you can live without the ability to play back frame sequences, you'll probably love VLC which is fast and free.




Updates:

8. ILM has a free and open source player for OpenEXR files available for OS X and Windows. Brendan Bolles (of the free OpenEXR AE plugin fame) has kindly compiled the
Mac OS X version and Windows version for those of us who are not comfortable around compilers.

9. Another PFClip is availbale for Mac OS X, Windows and several Linux 64-bit versions. Realtime 3D LUT support sounds promising, and the price is £199 excluding VAT.

10. Here's a dark horse; pdplayer doesn't have more than a small screenshot at the site, so if you know how to access the beta version, please post a comment.

11. Here's another tip via the comments: Jahplayer looks like a serious contender with GPU-based zoom and pan, RGB parades and 4K downsampling among others. It claims to play both DPX and OpenEXR and can also transcode into other formats. Add to that the fact that it's available for OS X, Linux and Windows, that it's free, scriptable and open-source (making it "easy" to integrate into current pipelines) and it sounds to good to be true. Please post a comment with your own findings!


So, what if you had $5,400 to spend? Well, you could get the FrameCycler DDS that plays directly from disk and outputs to external monitors via SDI.


Please post a comment if you know more players or have had good/bad experiences with any of them!

- Jonas

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2007-08-07

DPI in Video: Totally Useless



DPI = dots per inch is only relevant when you output digital images to an output device, such as a printer (or a display,) since DPI is a measure of how many of pixels the output device will show on a line that is one inch long.

That means that the DPI measurement is totally useless as long as you aren't printing. Video and things like DVD menus have a fixed size in pixels (called resolution) and DPI has no relevance. As long as you create the document with the correct size in pixels, you can set the DPI to 1 or 3,000, it doesn't make any difference.

To demonstrate this, open Photoshop with any picture and choose the command "Image Size..." from the "Image" menu and uncheck "Resample Image". You can then easily see that if you change the "Resolution" in pixels/inch, the actual pixel dimensions aren't altered, only the printed width and height are changed!

If you want to measure the DPI of a DVD menu, you must play the DVD and measure with a ruler on the TV set itself. You'll get a much higher DPI resolution on a small portable player than on a big hunkin' 60-inch plasma display, since you you are pushing the same amount of pixels to displays of different sizes.

The pixel resolution in square pixels (which is the preferred format when working in for example Photoshop) for NTSC Widescreen is 864x486 pixels, for NTSC 4:3 it's 720x540, for PAL Widescreen 1,024x576 and for PAL 4:3 it's 768x576. Don't forget the action-safe and title-safe either!

PS: The correct term is actually PPI (pixels/inch) for displays. The term "dots" comes from the raster dots that are traditionally used in printing presses.

PS. The only time the DPI/PPI is relevant is when importing/exporting graphics, like this Flash bug.

- Jonas

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2007-02-27

Shallow Depth of Field, Here I Come



Just a quick picture of this monster. I haven't calibrated it yet, but with a Sony HC3 (HDV 1080i), a RedRock Micro M2 adapter, a Canon EF-lens mount plus the Canon 70-200mm 1:4 L lens, and a DeckLink Intensity card for 4:2:2 HDMI capture to Premiere Pro, this setup will be able to provide a pretty decent picture.

The camera is on loan, I'm thinking of getting the yet unreleased Canon HV20 which is a 1080p25 camera, if it supports 4:2:2 HDMI capture.

I'm not sure what I'll shoot yet, but any ideas are welcome...

- Jonas

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2007-02-23

BBC Motion Gallery Updated

I'm a big fan of BBC's stock footage. In fact, the most expensive Swedish documentary ever could have saved a lot of money if they had bought all the shots of cute frogs and mean lumberjacks from BBC Motion Gallery instead.

- Jonas

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2006-10-30

Greenscreen and Bluescreen Checklist

Shooting for greenscreen or bluescreen? Here's a list of hard-earned experiences from the shoots where I've been vfx supervisor. I don't claim to be a chroma expert, so please post a comment if you have more tips to add to the list!

UPDATE: I've added some info on depth-of-field and motion blur as point number 2.

1. Keep it Blurry in Camera
Turn off all in-camera sharpening! This might make your director of photography (DOP) nervous and it will certainly make it harder for her/him to focus. On Sony cameras, there's usually two settings that need to be turned off: Detail and Skin Detail.

By default, all cameras apply a sharpening filter as a post-process before each frame is committed to tape/disk/memory card. While this makes the image look better, it is makes it so much more difficult to get a good and clean edge between your foreground and your chroma screen. Digital sharpening works by finding adjacent pixels of different lightness values and then increasing the difference, in effect crating a border with much higher contrast. Notice also how the in-camera sharpening brings out noise and imperfections in the chroma screen.

So shoot without sharpening and add it in post instead!



2. Keep it Sharp on Stage
While you don't want the camera to add artificial sharpening, you still want to keep everything in the foreground as sharp and correctly focused as you can. If the chroma screen is blurred in the background will only help to make it more evenly lit and textured, but you want to avoid having to key out blurred foreground, trying to separate it from the chroma.

If the blur comes from a too slow shutter speed or by too narrow depth-of-field, you'll have to tweak the keyer and possible sacrifice other parts just to manage the fuzzy edges. A blurred edge between foreground and background means that you will have to compromise between the edge and despilling settings, and quite possibly have to keyframe these settings to compensate for different levels of blur on different parts of the clip.

Instead, add motion blur in post by using optical flow technologies such as ReelSmart Motion Blur and add depth-of-field by layering chroma clips and post-blurring them.



3. Resolution and Framing
You want to shoot with as high resolution as you can afford, to make sure you keep your options open when you get to postproduction. Even if your finishing in SD, try to capture in HD or even 16 mm or 35 mm film. The more detail you can capture, the cleaner key you'll be able to pull. You can always scale down, but you can't get back image data that you haven't captured...

Keep a constant lookout for how the DOP frames the action. Since you'll be working with the shots in post, you can disregard the safe areas that are normally cut off by monitors and TV sets - that's 10% more image data to use!

I've found that I often have to keep pushing for tighter framing of each and every shot. To make sure that you and the DOP sees the entire image, set the camera viewfinder and the preview monitors so they are underscanned.

Even if you're shooting for a 16:9 production, you'll most likely want the set the camera for 4:3 aspect ratio, unless your shooting something that will fill the entire frame horizontally. Otherwise you'll be sacrificing horizontal resolution, making for rougher key edges.

Another way to squeeze the maximum amount of resolution from your cameras is to tilt them 90 degrees for shots of standing people.



Here's an example of three Sony Digibeta cameras with two of them tilted 90 degrees to capture standing people at maximum resolution.




4. Blue or Green?
What you are trying to achieve is to provide your keyer with a color channel that is as distinct as possible. Since human skin tones and lips tend to be red, that leaves blue and green. So which one to choose? That depends on a couple of things...

Green chroma screens have become more and more popular in recent years, largely because green provides a brighter color channel that tends to have less noise than the blue channel. The relative brightness of green makes it a bad choice for shooting blonde hair though, which is a lot easier to key against blue backgrounds.

The bluescreen has some distinct advantages. When you can't avoid a lot of spill (for example when you have to put the foreground very close to the chroma material) you can take advantage of the fact that we tend to find blue casts less disturbing than people walking around looking sea-sick with green faces. Also, when shooting for something that will be composited on to outdoor backgrounds and water, a slight blueish cast won't be a problem.

So if you are shooting a blonde with jeans, you'll have to settle for a compromise!



5. Don't Depend on the Crews' Imagination
Good storyboards that can be shown to the entire crew, both before the shoot (so that they can bring the correct gear) and during the shoot. Depending on the complexity of the shot you might need animatics, but at least bring sketches or printouts.

Talk to the crew so that they understand how stuff will be used in
post. For example, I have had instances where cameramen have cut off
talents' feet even though I've tried to explain that we needed the
whole body.



6. Don't Depend on the Talent's Imagination
If talents are supposed to look at things that will be added in post, make sure they have something (that can be keyed out later) to look at and interact with during the shoot.




7. Get Good Clothes
Make sure you avoid greens, browns and khaki for greenscreen shoots and jeans and other blue clothes for bluescreens. This cannot be allowed to be something you decide on location, it must be planned beforehand.



8. Get Good Props
Make sure you can dull-down shiny stuff so that they don't reflect the chroma color.

The choice of a shiny metal briefcase in the example above is a particularly bad one, considering it had to be rotoscoped in all the shots. The ear-ring was taken care of with an Inside Mask in Keylight.



9. Match the Lighting As If Your Sleep Depends On It
There's no substitute for good lighting and gaffers that can match foreground and background. You can fix almost anything in post-production, be relighting is among the hardest and least successful things you want to spend your nights with. There's nothing that screams fake as much as wrong lighting!



10. Preview Directly On Set
You can't underestimate the value of being able to compare a roughly keyed-out foreground against the background that it will be composited against. Not only is the immediate feedback important for the talent, it is also invaluable when it comes to matching the lighting and perspectives.

If you can't use a real-time keyer with a feed from the camera, like in the image above, at least bring a laptop and a digital still camera and do a quick key until the lighting matches perfectly.



11. Go Easy on the Tracking Markers
If you use tracking markers, make sure you have sufficient number in each shot, without having too many that you will have to paint-out in post. Try using markers with almost the same color as the screen, for example by using chroma tape, so that you can remove them by a second keying-pass.

The extensive number of markers in the example above comes from the fact that they were to be used for a tight head-shot during a 30 minute interview where the subject didn't want anyone except the interviewer and the DOP present. Therefore we had to make sure we had at least some markers visible at all times.



12. Avoid Unnecessary Spill
Keep the foreground as far away from the chroma screens as possible, since you'll have less spill to deal with. Make sure that all parts of the floor that might reflect chroma color onto the foreground are covered by non-reflective material such as black cloth.

It's up to you to keep each setup as far away from the chroma screen as possible, as people seem to be attracted to the big wall of color. It is your job to check that the entire foreground has chroma behind it during the entire take, which is why rehearsal is so important since it gives you the chance to spot potential problems which will force a setup adjustment.



13. Keep It Clean
Strive to keep the chromascreen as spotless as possible, and stop people from walking on it unnecessarily.



14. Get to Know Chroma Sampling and Codecs
Since chroma keying works on the principle of isolating one color, you would think that it was extremely important to get as much color data from the camera as possible. This is unfortunately not the case in many circumstances, especially when it comes to video. I won't get to geeky here, but you need to understand how digital video is stored.

The human eye is much more sensitive to the luminance/lightness of what we see, than to the color of the world around us. That's why all (but a few super-high-end cameras and formats) immediately throw away at least half of the color information that is captured. This is bad news for keying, since the less color information you have, the harder it is to accurately isolate a color.







If at all possible, you want to capture a 4:4:4 image without any color compression, and then keep that color resolution intact by using an appropriate codec at least until you have passed the keying stage. You should also strive to retain the more than 8 bits per channel of data that many systems capture, such as the 10-bit color depth of DigiBeta.

Trying to key of DV footage is even harder, since the DV codec only stores a quarter of the color data, using a 4:1:1 compression. If you have no choice but to key from DV footage, try to blur the U and V channels before pulling a key, or use a keyer that does this automatically, such as dvMatte from dvGarage.

Here's an example of the low horizontal color resolution of DV footage:




15. Frames Rather than Fields
Try to shoot progressive rather than interlaced, to avoid having to de-interlace the footage. If possible; shoot double the frame rate with progressive if you need to go to interlaced later. Avoiding interlacing not only gives you a cleaner edge and saves time on de-interlacing, but it also provides you twice the spatial resolution which might come in handy if you have to up-res in post.

Interlacing is an evil compression technique that severly limits your options, and you should always try to avoid it, instead adding it at final output.



16. BYOC: Bring Your Own Camera
Take lots of reference shots of locations, the lighting setup and other stuff that will help when you crawl back into your dark post-dungeon. You can never have too many reference shots!



Final Words
Avoid the temptation to think that problems on set can be "fixed in post." Everything that can be done in front of the camera should be done on set. Make sure the time allocated for postproduction is used to enhance the final outcome instead of fixing mistakes done when shooting.

Also, be prepared to pull several keys and to use garbage mattes and core mattes. Remember; you are trying to extract the edges, everything else can be mattes/roto'ed!

- Jonas

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