In my last post I discussed the emergence of 4K video production from the perspective of the end user or consumer. In this post I want to talk about the production end of things. Whether you’re in production or a client looking for production, it’s good to know what to be prepared for.
Now why would you want to start a 4K video production workflow? There is no broadcast infrastructure for it right now. HD broadcast and distribution online and through Blu-Ray is beautifully resolved on current computers, TVs, and even in theatrical releases. Here are my reasons for starting a 4K workflow.
- Shooting 4K and down rezzing to 2K or HD can often give better results than shooting 2k or HD.
- Shooting 4K allows creative cropping and image composition in 2K or HD post production.
- Shooting 4K allows for editing and delivery of films for theatrical releases projected in 2k or 4K.
- The particular camera I’ve invested in is one of a handful that use a global shutter resulting in no distortion of fast moving images or from panning as with a rolling shutter. Read about the differences here.
- 4K distribution, I believe, will develop faster over online outlets such as Netflix and YouTube.
- I’m a sucker for cool, cutting edge gadgets and technology!
Your reasons may vary and that’s perfectly fine. Keep in mind that these reasons alone are not all that go into making compelling video and movies, nor does every major feature film shoot in 4K.
Some say size doesn’t matter ;) Well in the case of 4K production, size most definitely matters! After a long wait, I recently received my Blackmagic Production Camera 4K and immediately started doing test shots. One of the first things I wanted to know was how much data it output. A :30 HD TV spot mastered in the ProRes 10 bit HQ codec takes up about 800-900 megs of disc space, close to a gigabyte. I did a 1 minute test clip in 4K ProRes 10 bit HQ on the BMPC 4K and it came in at 5 gigs! My AJA Data Calc puts it at 6 gigs! (I guess it’s better to be safe than sorry.) Shooting with my hacked and hotroded Panasonic GH2 at 100 megabits/sec 1080p HD yields about 45 minutes of footage on a 32 gig SD card. That’s a lot of data and requires a lot of SD cards for a large shoot. The BMPC 4K uses standard 2.5″ solid state computer drives or “SSDs” and I currently have a stack of 240 gig drives. At the estimate from the AJA Data Calc that gives us roughly 40 minutes of shoot time. At around $175 per drive, you can see that can rack up some cost. This is not even considering using a RAW workflow which will produce more data. Using 480 gig drives will cost $300-$400 each. That addresses in camera acquisition but you still need to consider off loading the data for on set backup. This requires a laptop and a large hard drive.
Some people prefer to offload data to a hard drive on set, then format the camera media to use it again (and you know who you are). I prefer NOT to do that. Instead, I prefer to off load the data to another hard drive and then take the camera media out of rotation with the data still on it. That way there are two copies on set. When the data is ingested to the edit and a backup is made on another hard drive, then I format the camera media. I also don’t like to switch camera media until it is full. This means you need to have enough SSDs on set to finish out a 12 hour shoot potential. In addition to the hardware, this production workflow requires a good AC or DIT to wrangle the data and ensure that all is backed up and logged.
Speaking of the edit, the post production requirements of 4K are more demanding as one would expect. I’ve already mentioned the additional space needed for archiving, but larger drives are needed for an online edit and the edit system itself needs more horsepower. I run a Mac based shop so the experience I have is from that perspective but whether you use Mac, Windows or a Linux based system, the principles are the same.
Thunderbolt, developed by Intel, is a fantastic interface. It is faster than fibre channel and offers the ability to carry data and video signals at the same time as well as offer external expansion of the computer system through Thunderbolt PCI express expansion chassis. There are many Thunderbolt enabled RAIDs available for media storage for the online edit. There is no configuration of hard drives right now that have a data rate that can saturate the Thunderbolt pipeline. That makes for smooth editing if all other elements are in place.
Today’s systems rely heavily on GPU accelerated graphics cards, meaning the graphics card takes up more and more of the heavy lifting not only in producing an image output to displays, but in the processing and rendering of the image inside the computer. I’m in the process of reviewing what I need to upgrade my shop and the current 27″ iMac makes sense for me. VRAM has become more important these days when spec checking. One gig is the minimum for practical use and the current 27″ iMac is available with up to 4 gigs VRAM. The new Mac Pro is a powerhouse and there aren’t many, if any, turn-key systems comparable to it out right now. It’s designed from the ground up for 4K post production and beyond. I’m editing my 4K through proxy footage right now and it works great.
Displaying the 4K image requires a capable GPU or an external device such as the Thunderbolt devices made by AJA and Blackmagic. I’ve discussed some options in my previous post and some things to consider about viewing 4K content.
There are more things that go into budgeting a shoot than simply what type of camera is being used. Post production work flow being one of them. I briefly mentioned a RAW workflow. The RAW implementation on Blackmagic’s 4K camera will be activated in a soon to be released free firmware update. This is another area where budgets can increase because of the nature of a RAW post production work flow. I’ll go over that in a future post. In the mean time, since the BMCP 4k is cable of more than 4K production, I’m going to have fun doing creative work with 4K regardless of the final delivery or purpose.