Let’s Get Rid of Arcane Aspect Ratio
and Resolution Numbers
I am absolutely baffled by the way we sell
our video features and technologies. We
know that our client base isn’t interested
in mathematical formulas, yet we keep
dishing out a dizzying array of divisions
and coded language to describe why they
should get excited about the latest and
greatest in visual display quality. Clients
that are confused by arcane aspect ratio
and screen resolution numbers are clients
that are not buying video products.
Who ever thought that consumers would
get excited about something called 16:9?
Are we going to get everybody knocking
on our doors because they think 21:9 is
better, or because they can dream about
4K instead of 1080p screen resolution?
I know that we are dealing with a lot of legacy rationales for all these
numbers. Take aspect ratios, for instance. The 1.33333 ratio (rounded to
1:33), which is also known as 4:3, came about from the way that Edison
and Kodak made their early films. The Academy of Motion Picture Arts
and Sciences later set this aspect ratio as its standard for shooting and
displaying movies in the early 20th century.
We need to stop
listening to our
engineers for marketing
and branding terms and
start coming up with
simpler methods for
our end users to figure
out the progression in
video performance and
The 1.77778 (rounded to 1.78) “HDTV ratio,” which is also known
as 16:9, resulted from a 1984 study to determine how wide versus tall
manufacturers could make CRT picture tubes before TV sets would
become unmanageably large for the screen size. By the time HDTV really
got going, CRTs were on the way out and the transition to fixed-pixel
displays was well under way.
The 2.35 aspect ratio (yes, that’s 21:9) is a survivor of Hollywood’s
widescreen revolution of the 1950s, when Twentieth Century Fox branded
the anamorphic photographic process used to create it as CinemaScope.
For various technical reasons the original “Scope” aspect ratio of 2.55:1
has been narrowed to 2.35 (or thereabouts).
And then there’s resolution... In the analog days we used to specify
horizontal resolution in MHz (number black-white-black transitions a
display could resolve) and vertical resolution in number of lines. Now
we’ve got a lot of pixels everywhere, but no consistency in how we account
for them. The 720p (1280 x 720) and 1080p (1920 x 1080) resolution
designations are named for their vertical pixel count. Meanwhile 2K
(2048 x 1566) and 4K (4096 x 2160) Digital Cinema formats are known
by their horizontal pixel count. Do we seriously need to burden our client
presentations–and their focus on the final experience–with long division
and inconsistent terminology?
We need to stop listening to our engineers for marketing and branding
terms and start coming up with simpler methods for our end users to
figure out the progression in video performance and quality.
First off, for aspect ratios, let’s just use the ratio number and not a
division process. That shows up clearly by just glancing. The progression
would look something like this:
In this approach, the larger the number equates to the wider (better)
presentation. Note that, in reality, there are also common film formats
such as 1.66 and 1.85, but these aren’t setting standards for equipment
and native screen construction.
Second, for resolutions, let’s all go with one direction, and stick to it.
It looks like the analog legacy of counting vertical lines no longer makes
sense, so let’s all agree to count horizontal resolution in pixels. This would
640 (640 x 480 SD 1.33 Ratio Pictures)
2K (1920 x 1080 HD 1.78 Ratio Pictures)
4K (Upcoming 4096 x 2160 Pictures)
Note that I am omitting the number for 1280x720 because, here
again, this is not really a relevant measure of display systems we
would be specifying and selling into our projects. I know that there are
subtleties between the home video versions of 1920 x 1080 vs. the digital
cinemaresolution of 2048 x 1556, but I don’t believe this will impact our
clients and our communication one bit.
4K to the Rescue
Digital Cinema’s 4K presents the ultimate solution, as projectors with 4096
x 2160 pixels will be able to accommodate all the common resolutions
and aspect ratios without the complicated and expensive addition of video
processors and anamorphic optics to stretch, scale, multiply, and squeeze. Any
time you add things like this to the video path, you introduce the potential for
quality loss and optical degradation. For now, we need to work on keeping the
terminology as simple and straightforward as possible, and look forward with
great anticipation to this new crop of displays that will allow both ultimate
flexibility. With some luck, networking pipelines will be large enough in
the near future to gives true 4K resolution without undue compression and
bandwidth limiting, and we’ll be able to give our clients images on screens
large enough to subtend 50 degrees of field of vision with 2.35:1 images.
Chase Walton contributed to this column.