Does size really matter?
Since DJI announced their new line of Mavic Drones the internet has been alive with drama. One drone, the Mavic 2 Zoom, has a swag of fancy tricks including a lens that can zoom. The other drone, the Mavic 2 Pro, doesn’t. Its lens can’t zoom, and it drops some of the cool party tricks found on the Zoom. Yet, it costs more.
The Mavic 2 Pro, however, inherits the 1-inch digital sensor that was made famous by the Phantom 4 Pro where-as the Zoom carries over the legacy 1/2.3” CMOS sensor from its predecessor.
What’s more, the Pro camera now features a lens with variable aperture, meaning users of the new drone are no longer stuck at f2.8 but can now adjust their aperture all the way to f11. This is an essential upgrade for photographers because camera lenses don’t perform at their best when they’re wide open. Aperture is also a vital tool used in controlling exposure. I won’t go into detail on this here but if you’re new to photography I have a blog on this very topic which would be helpful to read.
So, variable aperture and a 1-inch sensor. It’s understandable why the value in this seemingly mediocre combination may not be immediately obvious and why I thought this blog could be a good idea. I’ll leave the variable aperture where it is for now but if you’re one of the many who are wondering why the size of a camera sensor really matters than hopefully this might be of a little help.
Where it all began
The digital sensor topic has always been a crowd favourite. Die-hard photographers were coming to blows in the 90’s over the laughable suggestion that anyone could consider themselves deserving of a camera unless they shot film and had a dark room under the stairs.
Then came the megapixel race which sparked some of the fiercest online debates ever seen outside of ‘the dress’ and now, in the last few years, we’ve seen the topic come to life again with the emergence of drones.
Then came the drones
Pre-drones, things had calmed down in the camera world. Technology had become more affordable and good quality imaging was available in high end point and shoots, mirrorless cameras and low to high end dSLR’s.
When the first consumer drones started appearing, the photography world was still recovering from their beloved D800 and 5D Mkll pub fights and the whole movement flew largely under the radar (pun well and truly intended) but things moved rather fast. The early drones with their strapped-on GoPro’s quickly evolved into integrated cameras and the photography community started taking note.
The problem however, was that these early camera iterations were years behind the imaging technology curve. This partitioned the drone world into those who cared about image quality and those who didn’t.
It set in motion the tone for what has since become a successful go-to-market strategy and the convenient product differentiation which we’re seeing played out right now between the Mavic 2 Pro and Mavic 2 Zoom.
This is gripping – so what happened next?
I’m glad you’re excited because this is where it starts to get interesting. The war hardened, twice shy photographers who had survived the bruising IQ battles of days gone by simply couldn’t accept a step back in image quality.
In 2015 DJI announced an upgrade to its Inspire 1 – the Inspire 1 Pro with a micro 4/3rds sensor and the promise of acceptable image quality in a camera that could fly! The I1Pro with its X5 camera was an expensive piece of kit but the mere availability of it was a decisive message and finally gave good reason for photographers and non-photographers alike to be excited by drones.
Back on topic
The intention of that quick history lesson / ramble was to point out that those who care about photography, care about image quality. This is a pretty important point because many photographers invest countless hours, days, months and years learning and improving.
They do it because it’s something they love but all that hard work, all those long nights, long hikes, cold mornings, it’s all in an effort for the one common and often elusive goal of capturing the best photo they possibly can.
It's all about the light
The size of the sensor relates directly to how much light it is able to collect and use. Image sensors are made up of (little light sensitive spots) pixels or more accurately photosites, think of them as tiny little buckets collecting light. The bigger the photosites the more likely they are to have more photons hitting them.
Now here’s the important part. Photons = light. More photons = more electrons and electrons = information. This is the fundamental role of a digital sensor. It captures light, turns that light into information and uses that information to create a digital image.
Therefore, it stands to reason that if larger sensors contain more photosites than smaller sensors they can (and do) produce more information which all comes together to create a better and higher quality image file.
Understandably, this direct correlation between sensor size, information and a better image file is rather critically important part of the recipe for those chasing that afore-mentioned elusive goal.
Dynamic Range and low light
One of the common terms often referenced when discussing the benefits of larger sensors is Dynamic Range. Dynamic Range refers to the range of exposure stops between complete black and complete white (this is usually the point in which I would draw a little diagram to explain myself).
If a camera can produce 14 stops of dynamic range, that’s 14 full exposure stops of information that’s available in the image file between a complete shadow and a complete highlight. Despite this common theory, dynamic range isn’t completely dependent upon sensor size, but it certainly plays a very large role in the process.
Another example that’s often referenced in this topic is ‘low light’. Again, there are other factors at play in delivering low light performance but, remember light = information.
The less ambient light available (low light) the less information the sensor has to work with and produce. This is where larger sensors have an unfair advantage because regardless of the light, when we press the shutter butter, the camera needs to produce an image some way or another and it will demand the information from the sensor to do so, regardless of its quality. The effects of this are also known as image integrity and are most commonly realised in clipped and grainy shadows, a common dilemma in low light photography.
What does it all mean?
This all translates into higher quality and more useable image files. When you hear the term ‘pushed in post processing’ that’s referring directly to this. The integrity of the image is pushed to it's limits to produce the best looking final output.
Moving the shadow or exposure slider to the right in Lightroom to brighten the shadows first requires that information be available in the shadows. How much detail is available in those bright pink sunrises depends on how much information is available within the highlights of the raw file. Higher quality image files also allow for more expansive colour profiling and significantly better editing.
A quick reality check
Photography is all about light. I’ve repeated it here and elsewhere. The sensor size plays a gigantic role in aggregating a high-quality image file but it’s still at the mercy of light and the other tools needed to capture the light, such as the ability of the lens to deliver that light to the sensor in the first place. Here’s a quick analogy (Some of you might recognise this one from my Camera Settings blog).
You have a 3-litre bucket (large sensor) and the other guy has a 2-litre bucket (small sensor) and you’re both thirsty and in need of water (light) but the tap (camera lens) can only supply 1 litre of water (light). Your bigger bucket will not have an advantage here.
However, when the water is in abundance you’ll have a much higher chance of collecting more water and faster!
So, does size really matter?
All this may come across as trivial, but a deep-sea fisherman wouldn’t use a hand real if they were fishing for marlin, an avid cyclist would arrive at the start line on their child’s bmx and a photographer wouldn’t sacrifice image quality when they’re hiking into the mountains dreaming of capturing that amazing sunrise.
All these tools will do the job and the 1/2.3” sensor in the Mavic 2 Zoom will, indeed, capture beautiful photos. However if image quality matters to you, then unfortunately size absolutely matters as well.