To me, choosing between a cropped or full frame sensor format is the most important decision to make when buying your first DSLR or mirrorless camera, but maybe not for the reasons you think.
When I purchased my first DSLR, I didn’t even know sensor size was a thing. I thought about which brand was best and how much money I wanted to spend. Little did I know, these were not the most important considerations, especially long-term.
Both cropped and full frame sensor formats have their benefits, so it comes down to what is right for you. My goal is to help you make an informed decision when purchasing your first DSLR (or mirrorless) camera.
Though this subject can be super technical, I’m going to stick to plain English. No complex mathematical formulas to do your head in (sorry, not sorry).
There’s quite a bit to understand. If you’re the impatient type, use the table of contents to jump to the summary at the bottom. It won’t hurt my feelings.
When we talk about cropped or full frame sensor formats, we are referring to the size of the image sensor in a camera.
Responsible for translating the light seen through the lens into an image file, an image sensor is essentially modern day film. As DSLRs (Digital Single-Lens Reflex Cameras) are designed to mimic SLR film cameras, it’s no surprise we still use the standards set by film.
Full-framed sensors are equivalent to the size of 35mm film (~36 mm × 24 mm), and considered standard. Cropped sensors are anything smaller than this standard size.
If you currently take photos with a phone or digital camera, you already use a cropped sensor.
The below diagram provides a rough visual of typical cropped sensor sizes compared to a full frame sensor. Obviously, this is not to scale.
Why Do Crop Format Sensors Exist?
The number one reason the cropped format exists is cost.
Companies can manufacturer products much cheaper and make them more readily available for the general public. Most cameras you see new in the stores for $1000 or less have a crop sensor. Though, I’ve also seen cropped sensors cost the same as full frame cameras, which in my opinion is silly.
The second reason, is size.
Have you noticed that phone sizes keep getting bigger, and their cameras keep getting better? This isn’t a coincidence.
As phone manufacturers improve their camera technology, they also use bigger sensors. However, they can only be so big, so phones use a lot of computer technology to enhance images.
What Is The Difference Between A Cropped And Full Frame Sensor Format?
Though there are several key differences between the two sensor formats, the most notable is field of view.
A crop sensor is aptly named, as it crops the image. Simply stated, when using the same lens on a full vs a cropped sensor camera, you can fit more in a full frame. Let me show you what I mean.
Setting my full frame Nikon D750 on a stand, I took Image A using my 50 mm lens. As you can see, the frame fits the full can on the left side, all the way to a partial view of the can on the right. There’s plenty of space on the top and bottom of the photo.
Using the same positioning, for Image B, I used the same 50 mm lens on my Nikon D7000 with an APS-C cropped sensor.
You can clearly see the field of view on all four sides is significantly smaller. The image looks zoomed in, or rather cropped. Hence the sensor’s name.
Crop factor in itself is not a bad thing, for a few reasons.
Cropped Lenses And Field Of View
Camera manufacturers are completely aware of crop factor; therefore, they make specific lenses to deal with this issue.
Dividing the focal length of a lens by the crop factor of a sensor, gives you the equivalent view of a full frame sensor. For our example above, if I take my 50 mm lens and divide by the crop factor of 1.5 for an APS-C sensor, then I need a 33.33 mm lens to have an equivalent field of view of my D750.
I know, I said no complicated math, so let me show you what I mean.
Image C uses a 35mm lens (they don’t make 33.33 mm lenses) on my D7000 cropped format camera. It’s a very similar field of view to Image A.
Note: Despite the camera being in the same place, the angle of view is slightly off as the cameras are different sizes. There’s more in view on the right instead of the left, but hopefully you can still see they are roughly the same field of view.
As we see from above, to get the same field of view from a cropped camera as a full frame camera, you just need a different lens.
- Full frame camera with 50 mm lens = Cropped frame camera with a 30-35 mm lens
Best Thing About The Cropped Sensor Format
Remember how Image B looked zoomed in? Now consider Image D below. Which lens do you think has the greatest zoom capability?
In the simplest terms, cropped image sensors require smaller lenses to get a greater zoom.
In the lenses above, the one on the left is a 18 – 105 mm DX cropped sensor lens. This means it is equivalent to a 27 – 157.5 mm lens on a full frame camera. However, the much larger lens is only a 24 – 70 mm FX full frame lens.
Because cropped lenses are smaller, they are much less expensive. Though, it is worth mentioning, they are typically not made with the same quality materials of the larger full frame lenses.
The point is, you need an even bigger lens to get the equivalent zoom on a full frame sensor. So, the lenses made for cropped sensor cameras are cheaper, smaller, and also lighter than their full-frame equivalents.
This also explains why some amateur sports and wildlife photographers prefer cropped sensor cameras. They get the great zoom at a fraction of the cost and weight.
That’s the good news. Now on to the bad, and my biggest issue with cropped sensors.
Worst Thing About The Cropped Sensor Format
I know it all sounds very rosy, a less expensive body, cheaper and smaller lenses, but still great images. There’s always a catch.
When recommending a DSLR or mirrorless camera for beginners, most posts I’ve seen automatically suggest starting with an amateur model. I think there’s more to it, but here’s my short version.
Lenses are more of an investment than camera bodies. Not only do they typically cost more, but you’ll keep them longer.
If you are like everyone else who gets the photography bug, you’ll want to upgrade your camera body every 2-4 years to get the latest technology. However, if you stick with the same camera brand, your lenses stay with you.
Unless… you want to upgrade to a full-frame sensor from a cropped sensor. Which most folks who get serious about photography eventually want to do.
Now this becomes very expensive, as you have to upgrade your camera body and your lenses. This happened to me!
If I knew what I know today, I would have started on the least expensive full frame DSLR I could find. Even if that meant buying a used camera.
Luckily, with the emergence of “advanced beginner” models it’s not that hard to find a good, but less expensive full frame camera. Many of these utilize full-frame sensors, without the complexity of the higher end models.
Using Cropped Lenses On A Full Frame Sensor
Technically, you can purchase full framed lenses to use on a cropped sensor camera. However, as demonstrated in Image A and B, the sensor will significantly crop the field of view.
I know what you’re thinking, you clever person. Why can’t you use the cropped lenses on your full framed camera?
Nikon lenses are interchangeable; however, only full frame Canon DSLR lenses are interchangeable due to different lens mounts.
Here’s what happened when I put the 18 – 105 mm cropped lens on my full frame D750.
I’m sure I don’t need to point out the heavy vignetting around the image, as the sensor is larger than the lens viewing area.
However, Nikon’s full frame cameras do have a nifty function. You can switch from using the full sensor to a cropped version.
Great! You can now use your cropped lens. BUT! You’ve also paid a lot more money for a full frame camera just to use it as a cropped sensor and lose all the benefits. Pointless.
My advice, if you think you may ever want to upgrade to a full frame camera, start with a full frame camera. It will cost less in the long term as you can reuse your lenses (plus they hold resale value better). Just stick to a brand.
Other Reasons To Consider A Full Frame Sensor
Obviously crop factor is a huge deal. Yet, it’s not the only key reason people prefer a full frame sensor, despite the steep cost and heavy lenses.
Ever notice your camera phone takes great daylight shots, but noisy and blurry in dim light? Thank the sensor for this.
A bigger sensor collects more light. More light, better image.
Full framed sensors are better at dealing with low light situations, and minimize a lot of the noise. If you plan on doing a lot of night photography, I feel a full frame is a must.
Another argument people typically make for the full frame sensor is shallower depth of field. Personally, I don’t see much in this argument. If you commit to a cropped sensor camera, you commit to using appropriate lenses, which basically gets rid of this issue.
But, let’s quickly talk about megapixels and sensor size.
Megapixels And Sensor Size
First off, marketeers love to tout megapixels (MP), but sensor size matters more. A lot more.
Though this is another complex subject, many photographers like to simplify pixels to buckets of light (instead of water).
These buckets (pixels) sit on the sensor collecting light. The larger the sensor the bigger the buckets can be. The bigger the buckets, the more light these buckets can collect. As we already know, more light equals less noise and grain.
Even though a 24 MP full frame sensor and a 24 MP cropped sensor have the same amount of buckets, there’s more space on the full frame sensor for larger buckets.
Now, comparing two same sized sensors, more megapixels means higher resolution. More resolution, the larger you can print, the more you can crop in post processing, and the bigger you can display your images.
Honestly, as a beginner, don’t get caught up in the megapixel game. Unless you want to print massive photos, or heavily crop in post-processing, any full frame camera with at least 12 MP will give you great images. Save your money for good lenses.
How Do I Know If A Camera Has A Cropped Or Full Frame Sensor Format?
The best thing to do before buying any camera is to do some research online. Look at the camera’s specs, specifically under sensor size or camera format. Here it should clarify full frame or APS-C (cropped).
Lenses are a little more challenging. You must know the camera brand’s mounting format. Let’s take the two biggest brands out there, Nikon and Canon.
Nikon only uses one mounting format for their DSLRs, F-mount, and one for their mirrorless, Z-mount.
- Cropped sensor cameras are their DX series. Look for lenses that reference a DX / F-mount (DSLR) or DX / Z-mount (mirrorless).
- Full frame sensor cameras are their FX series. Look for lenses that reference a FX / F-mount (DSLR) or FX / Z-mount (mirrorless). Often they are not marked as FX since they are usable with both full frame and cropped sensors.
Canon is different, you can’t mount a cropped sensor lens on a full-frame camera body and they have four mounting formats.
- EF-S for cropped sensor DSLRs only. These are the lenses that give cropped sensors the full focal distance without cropping.
- EF for full frame and cropped sensor DSLRs. However, as we saw in the example, the field of view is smaller using these lenses on a cropped sensor.
- EF-M for cropped sensor mirrorless cameras.
- RF for full frame mirrorless cameras.
Summary
I hope you have learned something, and now feel confident to pick out your first DSLR or mirrorless camera. Let’s recap on the key points.
- A camera’s image sensor translates light into image data files. It’s the most important part of any camera.
- Sensor size is more important than megapixels.
- The bigger the sensor, the better it handles low light situations. Minimizing noise and grain.
- Cropped sensors are popular because they are less expensive, and the lenses are smaller and lighter.
- Though cropped sensors provide a smaller field of view, lenses made specifically for them compensate for this issue.
- Cropped sensor lenses shouldn’t be used on a full frame camera.
- However, full frame lenses can be used on a cropped sensor, but it will crop the field of view.
- Lenses are more of an investment than camera bodies and you will want to keep them longer.
- If you think you may ever want to use a full frame camera, then start with a full frame camera to avoid re-buying lenses as you upgrade.
I’m curious, which sensor format is right for you – cropped or full frame?
If you have any questions, please leave them in the comments and I’ll try to answer them.
For more articles on photography, see our photography archives page.
