Full frame or crop sensor? A practical guide for the traveling photographer.

The eternal question that plagues many a photography forum: “Should I get a crop sensor camera or spring for a full-frame?” Comment sections are filled to the brim with debate.

For travel-focused adventure photographers like myself, the initial answer seems obvious. A smaller sensor in a smaller camera will be much more friendly to tote around. Of course, any amount of time spent on instagram will show some folks lugging a Canon 5D and twenty pounds of gear through a snowstorm just so they can get that perfect shot. On almost every occasion, the people lugging the 5D’s have results that speak for themselves.

So what’s a budding travel photographer to do? Is a larger camera going to be worth the extra weight? Just how much better does a full frame perform?

In order to answer these questions it’s probably best we start by identifying the key difference that set the two types of sensors apart.


The differences


1. Crop Factor

First and foremost, let’s get the easy stuff out of the way. Crop sensors are given that title because, well, they crop things. (Usually by a factor of around 1.5-1.6 to be exact.) This means that photos you take with a full frame will have a wider viewing angle when using the same lenses in comparison to a crop sensor.

Naturally, you can always buy lenses that are wider / tighter to suit your needs no matter which camera format you use, but it’s definitely something to consider if you ever think you’ll need to push the viewing angle of your shots to either end.

For tighter shots, crop sensors have an edge. If you’re looking to go wide, full frame might be what you need.

2. Camera Size

Another pretty clear difference is, of course, the physical size of the camera. Bigger sensors take up more space. So more often than not, a full frame camera will always be larger than its crop sensor brethren. There are some cameras that are starting to push this boundary a bit however. For example, the Sony series of full-frame mirrorless cameras have become the system of choice for those that want a full frame with less bulk.

3. Weight

Closely related to size comes weight. While differences in weight may not make much of a difference shooting in a studio, when you’re 3 days deep into the Alaskan bush, every ounce will start to feel like pounds. Crop-sensor cameras almost always have the advantage here as well.

4. ISO performance

Now here’s where we start to get into the real meat of the issue: performance. I won’t get too deep into the science of sensor tech, but the best way I can explain it is that the larger a surface area per megapixel, the more light information it’s able to take in at once, and thus the more accurate it’s data will be when there’s less light to work with. (Techno-wizkids please correct me on this if I misinterpreted something.) The bottom line is that larger sensors typically have less grain and noise at higher ISO sensitivities.

5. Depth of field

Another important technical aspect you’ll want to consider if the depth of field. Depending on what kind of shooting you’re doing it can be beneficial to have a more shallow focus depth. In this edge-case, full frame comes out on top. Shots taken at the same aperture setting with full frame cameras will have shallower depth of field every time. This is again due to the larger surface area and how it interacts with the size of a lens’ aperture.

6. Dynamic range

If you’ve ever snapped a photo on a high-end camera and immediately thought “wow this camera takes great photos,” but weren’t really sure what makes it so different, one of the things you’re probably noticing is the dynamic range. Dynamic range is basically the “range” of values a camera has between what it interprets as the blackest black and whitest white. The higher the range, the more depth of color and tone you’re going to get out of a camera. Historically, full frame cameras take the cake on this one as well.

7. Cost

The final variable we’re looking at today is probably the one that will ultimately make the most difference in our buying decisions, and that’s price. There’s no denying it, full frame cameras are quite expensive, and the lenses designed for them can also be pricier as well. When looking at cost for a camera it’s important to factor in the whole ecosystem you’re buying in to. Is it better to buy a cheaper camera with better lenses, or an expensive camera with lower-quality glass? Now it may depend on just how cheap a camera you buy, but in my experience buying better lenses has a much higher return on overall image quality than buying a really high-end body.


Putting them both through their paces

As a proud owner of a Fujifilm XT-2 (a crop-sensor camera), my research into full-frame made me question the quality of photos I could take, even though I’ve been largely overjoyed with my Fuji's performance. While I could spin this into a cautionary tale of reading too much on the internet and “fear of missing out,” instead I’ll just jump straight to some of my tests.

Now, I’m fortunate enough to have access to a Canon 5D mkIV through my job, which made procuring a test subject for my experiments much easier. To make things even better, the Canon is equipped with a 50mm lens which is roughly equivalent field of view to the 35mm lens on my Fuji.

What I tested

Hot off my internet-knowledge-binge-extravaganza, I decided I wanted to do some quick tests of what I considered the greatest apparent drawbacks of a crop sensor:

  • Dynamic Range
  • Depth of field
  • ISO performance

Dynamic Range

First up was dynamic range, that oh-so-magical “secret sauce” that makes a good photo even greater. For this test I set both cameras on the same tripod facing a scene with a backlit window. My theory was that whichever camera had higher dynamic range, would show more detail in the overexposed exterior of the shot.

Fujifilm XT-2 vs Canon 5D mk IV

At first I was downright shocked to find more exterior detail in the Fujifilm’s shot. (Take that Canon!) However upon closer inspection, I noticed there were some other factors at play.

For starters, if you look at the white tables in the Canon shot above, you’ll notice that they are brighter than the tables in the Fuji shot. This means that as a whole, the Canon camera was exposing the image slightly more than the Fuji. Perhaps each of the Canon’s ISO settings are just a touch more sensitive, I’m not sure. Regardless, a brighter image overall means a brighter exterior behind the window, and thus, a horribly skewed experiment.

Bummed about my lack of scientific accuracy and inconclusive results, I still managed to feel pretty good overall about the inherent ability of a cropped sensor to pick up dynamic range. After all, the dynamic range of the XT-2 is fairly well regarded around the web, and part of the reason I bought it in the first place.

Depth of field

While I didn’t set up a specific test to explicitly explore the DOF, it became extremely apparent in the pictures I took that there was a difference.
The difference in depth of field (DOF)
At the same aperture setting for both cameras, you’ll notice a lot of elements in the 5D’s shot appear blurrier, that are much sharper in the Fuji image. (I set the autofocus point at the same table corner for both cameras.) This isn’t to say that shots on the Fuji will always be sharper / better. In fact, there are some scenarios, like portraiture and shooting smaller objects, where a shallower depth of field is preferred to separate the subject from the background. While it’s not something that’s of great concern for me and the type of shooting I do, it’s a definitive quality that may be worth considering.

ISO

The last of my tests was focused on testing how much grain I’d get at the same ISO settings for each camera.

ISO grain detail at 100% resolution

To my surprise, I found the amount of grain in the two photos to be comparable. Ignoring the blurry edges of the chair in the Canon photo, (that small DOF is real guys) you’ll notice that the grain in the Fuji shot appears somewhat finer at 100% crop than the Canon, which has larger patches. The Fuji’s grain, however has more color noise mixed in, (like someone sprinkled some RGB all over the shot) whereas the Canon’s is more accurate in that regard. When I look at both and squint my eyes a bit, the Canon’s larger patches seem to be more apparent overall, although I can imagine that, at even higher ISO’s, the Fujifilm’s color noise will start to get very troublesome very quickly.


Putting the debate to rest

So after all the online research and testing of my own, I can’t help but feel like the whole question is a bit of a farce. Does the literal size of the sensor actually make a difference in image quality or does the engineering of that sensor matter more than it’s surface area? Have all the online debates been heavily skewed by the fact that most crop-sensors have been designed for the intro and beginner markets? My experience with how well the Fuji keeps pace with a 5D certainly lead me to believe it. Sure, the 5D will have shallower depth of field, and I think you could argue it’s ISO grain is more accurate due to color (thought I still prefer the finer grain of the XT-2), but is that bump in quality really worth the extra two thousand dollars? Maybe for the right person.

For me though, the lighter build, smaller footprint, and lower cost of a crop sensor camera is, and will continue to be, the perfect fit for a travel-conscious setup. But I’m curious to hear what you guys think. Hit me up with a PM on instagram either @mountainsandmaritime or @mitchellwadeharris and tell me what kind of kit you prefer.


Further reading and sources

For all of your technological questions and for testing under more controlled surcumstances check out this forum post over at Pentax Forums.

If you're looking for a more down-to-earth comparison, Aaron Taylor put out a great article about his experience switching from an entry-level Rebel T3i (same as my first camera!) to a full-frame 6D.

Mitchell Harris

Mitchell Harris

Mitch reps the "mountains" part of Mountains and Maritime from his home in the Appalachians. A designer by trade, he's all about putting way too many spaces in the word "aesthetic."

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