The APS-C Debate
Should you still buy a full-frame camera?
There is an ongoing debate about cameras with an APS-C sensor. Many seasoned photographers consider them as being inferior and just a cheap alternative for a “real” camera. But a lot has changed in recent years, and APS-C will be the future of photography.
Disclaimer: I own a modern APS-C camera (the Canon R7) and I am very happy with it. So I am obviously biased.
Just a crop sensor
I hear this so often. APS-C just does some additional cropping. Recently I posted a reply on Facebook where I said that a 1x magnification macro lens on an APS-C camera basically has 1.6x magnification. The obvious reaction of some readers was: “No, it is still 1x, just with an additional crop.”
Theoretically, that may be true, but the reality is different. In another post, I wrote that a 50 mm lens on an ASC-C camera was like an 80 mm lens. Same reaction. Again, theoretically correct, but a 50 mm lens behaves quite differently on an APS-C camera than on a full-frame camera.
Considering an APS-C sensor as “just a crop” does not do justice and does not give such a camera the credit it deserves. It would be the same as saying that a full-frame camera “just enlarges” the image area.
Both types of cameras have their virtues and uses. We should stop considering the APS-C camera as a stepping stone towards a “real” full-frame camera. And full-frame cameras might actually become obsolete except for very special uses, as the old 4x5" cameras did.
Zoom and magnification
APS-C cameras typically have a crop factor of 1.5 or 1.6 (for Canon). This means that the effect of lenses is different than on full-frame cameras. If you use the same lens, you end up with an image of a smaller area. So to get the same image, you need to move further away or use a wider lens. A 50 mm lens on my APS-C camera has the same effect as an 80 mm lens on a full-frame camera. This has positive and negative effects.
If you want to photograph landscapes you often want a wide view. This is a problem with APS-C cameras. You need a lens with a smaller focal distance, like 10 mm. Even though these would be easy to make for APS-C cameras, they are often not available.
But for wildlife the opposite is true. Your 500 mm zoom lens effectively becomes an 800 mm lens. And the lens dedicated for APS-C can also be considerably lighter. At the moment you see many wildlife photographers switching from their full-frame cameras to APS-C.
The same is true for macro photography. You effectively get an additional 1.6 magnification factor. An additional bonus is that when using the same magnification, you get a much larger depth of field. For this reason, macro photographers have been using APS-C cameras already for quite a while.
Dynamic range and low-light performance
Full-frame cameras with the same resolution have larger pixels on the sensor. This has some clear advantages. Larger pixels can collect more light and they can more easily distinguish between light intensities. Firstly, it means that they can work better in low-light conditions, introducing less noise. Secondly, it means that the dynamic range increases, which is particularly useful when you shoot in RAW and do post-processing on your images afterward.
Of course, a lot depends on the quality of the sensor. This has improved considerably over the past years. A modern APS-C camera performs better than a five-year-old full-frame camera. And it will improve further. Unfortunately, at the moment manufacturers seem to invest more research in better full-frame sensors. But hopefully, this will also improve the APS-C sensors.
Another development is software, both inside the camera and in post-processing. The new AI techniques are amazing in reducing noise. When I use ISO 6400 on my Canon R7, the JPG images that the camera produces still look great. The RAW images obviously have noise, but a modern AI noise reduction tool (I use ON1 PhotoRAW) makes these images great again.
Alternatively, full-frame cameras can have a higher resolution than APS-C cameras. But in this case, the pixel size goes down and, hence, the low-light performance and dynamic range go down as well. An APS-C sensor with 20 MP has the same pixel size as a full-frame camera of about 50 MP. And why would you need more pixels? Yes, to crop.
The bokeh
This is always an important argument for full-frame: It give a much better bokeh. You can make the background much softer. But this is only partially true. As an APS-C sensor “just does a crop”, the background actually looks exactly the same.
The difference occurs in how you use the camera and lens. To create the same image as the full-frame camera, without the crop, you need to zoom out more or use a wider-angle lens. This increases the depth of field and, hence, the background becomes sharper. What is a blessing for macro photography becomes a curse for e.g. portraits. But there is an easy solution: open the aperture. You can do that because of the depth of field of the APS-C sensor. So your subject will still be in focus.
It is possible to make APS-C lenses with wider apertures than full-frame lenses, at a lower cost. But the manufacturers don’t do that at the moment. So, with the current lenses available, you indeed need a full-frame camera for the nicest bokeh. But this can change in the future and is not a problem of APS-C per se.
Price and weight
APS-C camera bodies are considerably cheaper than full-frame cameras. But this is not a blessing. Of course, the sensor is somewhat cheaper, but the main reason for the price difference is that they have fewer features.
I would prefer a more expensive body that has all those features, like a stacked sensor. Also, the body is often lighter and smaller. I do not like this. I prefer the form factor of full frame cameras. The Canon R7 that I have is fortunately close to that, but it was one of the reasons for me not to buy a Sony APS-C camera.
For lenses though, it is a different story. It is considerably cheaper to create a lens for an APS-C camera. My 18–150mm RF-S lens has remarkable quality for its price. But manufacturers are still reluctant to produce high-quality lenses for APS-C.
For example, the L line of top-quality lenses of Canon has no APS-C lenses. And the weight of the lenses can also go down considerably, making it easier to work with them.
The manufacturers
The manufacturers play an important role in positioning the APS-C camera. Unfortunately, at the moment, they do not position it as an alternative to full-frame, but as an entry-level model. The bodies do not have all the features, and they do not have the same form factor. There is only a limited number of APS-C lenses available and they have not the same quality. You can of course use the full-frame lenses on APS-C cameras but then you lose all advantages.
The manufacturers should do the following:
- Create better APS-C camera bodies with better (stacked) sensors, larger buffers, all controls, and so on.
- Create more and higher quality APS-C lenses.
- Create lenses with wider angles for APS-C such that you can make similar images as with full-frame cameras.
- Create APS-C lenses with a wider aperture.
But they don’t do that at the moment. From a business perspective it is probably not a wise thing to do yet, but, like with the move to mirrorless, at some point one manufacturer will take the step and others will follow.
The future
When there would be APS-C cameras with the features of the best full-frame cameras and when there would be APS-C lenses with the same variety and quality of the full-frame lenses, APS-C would become the camera of choice for most photographers.
The slight improvement in dynamic range and low-light performance of full-frame cameras would be useful to some, but for most of us it would not be a deciding factor. The advantages of being cheaper, lighter, and more versatile, would outweigh that. And software (both inside and outside the camera) could solve most of the limitations.
Photography becomes more and more computational anyway (but that is for a future article).
The manufacturers will not be happy with this development. It will make cameras and lenses cheaper and, hence, reduce their profits. They prefer to sell highly overpriced and very heavy full-frame lenses, rather than invest in making our life easier. But it will happen, or they will loose the battle with mobile phone manufacturers.
Please let me know your thoughts about this in the comments below. Will your next camera have an APS-C sensor?
Mark Overmars is a dedicated insect photographer that loves to share and regularly publishes about his work and about photography in general. You can visit his website at www.insectphotography.org. Download his free insect photography book at www.insectphotography.org/book.
