SHOULD I SHOOT IN 4K IF I AM DELIVERING FULL HD?
Written by Nigel Kettle
At Kettle Media Concepts, we are frequently asked by our clients if the should should in 4K for finishing in full HD or just shoot in standard HD?
The Short Answer:
Yes, we strongly recommend shooting in 4K, even if your final delivery is going to be in full HD. Think of 4K as twice the resolution of full HD. This means that you can zoom in a full 50%. Your image quality will look just as good in HD. This is a great substitute for the absence of a second camera. This can be very helpful in covering jump cuts that is an annoying problem that plagues all one camera shoots. As a matter of fact, if you are only shooting with one camera, it is imperative that you shoot in 4K, if it is an option. This will save you so much heartache later in post.
It is worth noting the camera angle is always the same on the zoom when you shoot in 4K. While this may seem obvious, I am often asked by clients, if it can’t be used as a second angle. No, it cannot. The bottom line is, shooting in 4K cannot be used as a substitute for multi angle shoots, but it can be used for close-ups. Note that your zoom range is roughly 50%. This comes in very handy when working with interviews and b-rolls.
Most edit programs, including Avid Media Composer and Adobe premiere have easy-to-use built-in workflows for this. The process is very simple. I will address the various workflow in an upcoming blog.
Interested in some of the technical jargon behind this recommendation.
A More Detailed Explanation:
Yes, we strongly recommend shooting in 4K, even if your final delivery is going to be in full HD. 4K can sometimes be confusing because its vertical pixel varies, (example: 4096 × 2160 (full frame, or 4096 × 1716 (CinemaScope crop) However, more often it is usually (4096 x 2160) or Ultra HD, referred to as UHD (3840 x 2160) that are the common sizes used. In terms of aspect ratio, UHD is the same as full HD. They are both 16 x 9 images. UHD is basically regular HD doubled. Full HD (1920x1080) times two, gives you UHD-4K (3840x2160). The math is (1920 x 2 = 3840) 1080 x 2 = 2160) Since both aspect ratios are the same, they fit perfectly in any regular 16 x 9 HD television set. However, if you shoot at standard 4K (4096x2160), you will have a strip of black at the top and bottom of your screen (see Fig. A). To avoid this, you will have to zoom in a little. When you zoom in, you will inevitably have to cut the left and right sides of the video. For this reason, if the video was not shot with this in mind, some pan and scan may be necessary. This could increase your post-production budget a little.
Once I explain this, one of the follow-up questions is usually about hard drive space. “But won't the footage take up a lot more storage space?” Hard drives are cheap. Gone are the days when you would blow your budget just on hard drive space. This isn't a big issue anymore. I strongly recommend transcoding the footage to a low-res version for your edit session anyway. This saves on hard drive space for the edit and speeds up the process since you don’t have to bog down your computer with bulky files. You will spend less time waiting for long renders due to large hi-res files. Aside from the raw footage, you never really have to worry about storage.
In conclusion, if it is not going to affect your shooting budget much, shoot in 4K or 8K. For a smoother more trouble free finishing, I recommend shooting in 4K-UHD or 8K (7680x4320). Note again that 8K is just full HD times four. It is still a 16x9 image.
Look out for my upcoming article about setting up your workflow in Avid Media Composer and Adobe Premiere for finishing in full HD.