The mirrorless camera was originally announced as a smaller, lighter and more convenient alternative to the DSLR. However, if you look at the latest mirrorless cameras from Canon, Nikon, and (to a lesser extent) Sony, this doesn̵
Canon’s new flagship mirrorless camera, the EOS R5, weighs just under 26 ounces and measures 5.43 x 3.84 x 3.46 inches. The company’s next equivalent DSLR, the 5D Mark IV, weighs 31.4 ounces and measures 5.94 x 4.57 x 2.99 inches. While there is definitely a difference, and the R5 is lighter and smaller (in most dimensions), it’s not exactly day and night. Then of course you have to add a lens as well.
If you put an RF 24-105mm f / 4 L IS USM (24.5 oz) lens on the R5 and an EF 24-105mm f / 4 L IS II (28.1 oz) lens on the 5D , the total weight increases to 50.4 and 59.5 ounces, respectively. You will feel the difference when you hold both of them at the same time. However, it’s not a particularly easy setup either – in fact, they’re pretty much alike.
But here’s the real kicker: The RF 24-105 and EF 24-105 are similar in size and offer powerful lenses. One of the greatest advantages of mirrorless cameras is the use of brand new lens mounts so that manufacturers can make even better lenses.
The mirrorless replacement for the incredibly popular EF 24-70 28.4 ounce f / 2.8 L II USM lens is the RF 28-70 f / 2.0 L USM, which weighs in at an absolutely ridiculous 50.4 ounces. If you put that on an R5, the total weight is 4.75 pounds compared to 3.74 pounds of the 5D and its 24-70mm lens. Now the mirrorless camera rig weighs more!
How did we get here?
Manufacturing decisions by Canon and Nikon
The main reason mirrorless cameras aren’t smaller and lighter is simple: Canon and Nikon didn’t want them to be. We’ll get into why a little later, but first a quick history lesson.
Canon and Nikon’s DSLR platforms are technologically ancient. Canon launched the EF mount in 1987, while the first Nikon F mount lenses came out in 1959. This is basically a prehistory.
While Canon and Nikon have made good use of their lens platforms, they have now encountered tough physical limits that will allow them to advance them further. Canon would probably have liked to release the Monster RF 28-70 f / 2 that we mentioned above for its DSLRs.
However, due to the design of the lens mount, the company was unable to produce an equivalent lens. Canon has been limited to 24-70mm f / 2.8 for decades.
When it came time to design a new lens mount for their flagship mirrorless cameras, Canon and Nikon just didn’t choose to get smaller – they got bigger. By removing the mirror, they were able to reduce the distance between the lens and the sensor, which improves image quality. By widening the frame, lenses with larger apertures could be produced.
You now have more opportunities to innovate, which means bigger, crazier lenses.
In theory, Canon and Nikon (and before that Sony) could have made smaller lens mounts, but that would have limited them further.
This brings us to the next reason why mirrorless cameras are still so big.
The size of the lenses
While cameras get a lot of attention, it’s the lenses that do most of the hard work in photography. A major problem for manufacturers who want to make things smaller is the laws of physics.
A full-frame camera sensor is standardized from a piece of 35 mm film. They are 36 x 24 mm and cannot really be changed. Sure, there are smaller image sensors like those used in smartphones and APS-C cameras, but they involve a number of tradeoffs.
The high-end amateur and professional photography industry is based on the 35mm standard, including lenses.
The relationship between the focal length of a lens and the size of the sensor affects its appearance. In a full frame camera, wide-angle lenses have focal lengths of less than about 40 mm, while telephoto lenses have a focal length of more than about 70 mm. In the middle are the normal lenses, which offer a perspective similar to that of the human eye.
However, the focal length is a physical property of a lens. A lens with a focal length of 100mm doesn’t have to be 100mm long, but it is in this stadium.
As long as camera manufacturers are committed to making a full-frame camera, they will also be committed to lenses of a certain (rather hefty) size. There are small savings that can be made by using lighter materials or more compact designs. However, there is no way a 24-70mm zoom lens could be much smaller than it is now and is good.
Since the lenses have to be of a certain size, so do cameras. Because of this, Canon’s lightest full-frame mirrorless camera, the RP, is still 17.1 ounces – about 2/3 the weight of the flagship R5.
Even the cheaper, lighter cameras still have to work with the same lenses.
The decline of the consumer camera market
So far we have focused on the high end of the camera market as this is the part that offers manufacturers the greatest hope.
Since 2010, global sales of digital cameras have fallen by 87 percent from 121.5 million to 15.2 million. Smartphones stole the low-end consumer-facing camera business.
Since almost everyone who wants a small, lightweight, and easy-to-carry camera already has one in their pocket, there is little incentive for manufacturers to develop a competing product.
Mirrors have never been this big
Part of the discussion about camera size and weight that is lost a bit is that the mirrors in DSLRs weren’t that big at all. They take up some space (which is why mirrorless cameras are slightly smaller), but were never particularly heavy. The sensor, electronics, battery, LCD screen, viewfinder, SD card slot, lens mount, etc. are still there.
As mentioned earlier, manufacturers also used a bit of the size and weight saved to go with more advanced lens mounts. It’s the same reason why removing headphone jacks from phones has not resulted in smaller, lighter-weight phones, but rather more advanced phones.
Are there small mirrorless cameras?
If you really want a small, lightweight, mirrorless camera, you’re in luck! They exist, they just aren’t flagship products for most brands. This is because the compromises required to do this don’t lend themselves to excellent technical data sheets.
For example, Canon has the EOS M range of APS-C mirrorless cameras. Sony’s Alpha line also includes numerous APS-C models. Unfortunately, since these use the same lens mount as the full frame cameras, most lenses are still quite large.
However, the mirrorless range finders in the Leica M series are as compact as a full-frame camera.