Mirrorless Advantages
Size & Weight
There is no doubt that going mirrorless can save you some size and weight. This was one of the big reasons I jumped ship. I cut the size and weight of my setup by 50%…that’s huge! And trust me, I feel it every day I’m out shooting and traveling. I think it’s worth it alone.
Mirrorless cameras are able to be built in a more compact manner because they don’t need all the additional equipment to capture a frame (the prism and mirror).
Autofocus
As I said in the DSLR section, autofocus is excellent with mirrorless cameras. And because of firmware support updates, it’s able to be improved after your purchase. We have seen this with Nikon’s Z line and many others.
I think Sony probably has the best AF system out there right now, with the A9 II setting the bar. Although, the Canon EOS R5 has made a splash as well.
Anyway, I just want to say, I don’t think you will be limited by the AF system of your camera. The hybrid focusing detection systems are excellent and getting better. That added with features like Eye-AF that can track people and wildlife is a bonus too, but you can find DSLRs with those features as well.
Burst Rate
Because of the way mirrorless cameras capture and transmit light, they are able to achieve faster burst rates than their DSLR counterparts.
The best mirrorless cameras today can capture 20 fps, while the best DSLRs are around 14-16 fps. You can find professional low-end mirrorless cameras that can easily capture 10+ fps too. The DSLRs that can do 14-16 fps will cost you a pretty penny.
This is a big deal for wildlife photography. The AF systems continue to improve and the burst rates are awesome…we just need the lenses (unless you’re a Sony user).
Electronic Viewfinder
The main benefit of the EVF is – what you see is what you get. I mentioned I preferred the optical viewfinder, but I’m getting used to the EVF. I used to use exposure simulation with Live View on my DSLR, but now changing settings and seeing them instantly reflected on the display is a breeze (and awesome). The EVF system is really growing on me.
Image Stabilization
Image stabilization is a HUGE consideration. Many DSLRs have lenses that are stabilized, but mirrorless systems offer in-body stabilization AND lens stabilization in some cases, allowing for insane control over movement and vibrations.
I’ve handheld with Sony and Nikon cameras down to 1/5s, and shots have been sharp. Who needs a tripod? But, seriously, the in-body stabilization offered by many mirrorless cameras is a huge plus and I think it could become a game-changer as technology improves.
Video
Many mirrorless cameras have become video superstars. Most DSLRs are not able to use their highly accurate phase-detection focus systems when the mirror is up, meaning AF can be unreliable. Mirrorless cameras have their phase-detection focus pixels baked into the sensor, so there is no focus limitation.
We’re also seeing incredible bit rates and recording modes introduced to mirrorless; 4:2:2 modes, 10-bit modes, and log support.
So, that mirrorless you purchase for stills is most likely packed with video features as well.
DSLR Disadvantages
Size & Weight
DSLRs are big. Especially with professional-grade, super-fast lenses attached to them. This was my main reason for switching. I cut my weight and overall size by 50%. I had a 14mm-24mm f/2.8 with a bulbous front element so I needed to carry around this huge pancake of a filter holder just to use a circular polarizer.
Now, I use a 14-30mm f/4, that takes threaded filters and weighs 2lbs less. My Z7 is also considerably smaller than my old Nikon D810. Now, mirrorless cameras still have some pretty big lenses, but overall you are going to save size and weight with a mirrorless camera body and most lenses.
Burst Rate
We touched on this, but no doubt about it, DSLRs will not (at least currently do not) shoot as fast as their mirrorless counterparts. In general, the faster the better for wildlife so it might potentially be worth it to look into a Sony A9 II or Canon EOS R5. The lenses are still the limiting factor though, as it will be quite a few years before some of the super-telephoto primes are released.
Mirrorless Disadvantages
Lenses
This is mainly for Nikon and Canon, but we just don’t have the native lenses yet. A lot are being released, and I’m sure many were delayed by COVID, but the DSLR systems have so many more options. There are way more third party options too, which can be excellent.
This is more of a waiting game though, in time, the Nikon and Canon mirrorless systems will have a full offering of amazing lenses. And speaking from personal experience, the technology and design of the new mirrorless lenses are blowing some of the DSLR lenses out of the water. A lot of that has to do with the flange design on the new Nikon and Canon mounts.
Ergonomics
You save size and weight, but you get a smaller camera body. It probably won’t feel as good in your hands and you might find you don’t have as many button options, or the layout is just a bit cramped.
There’s no way around it, but I’ve found that the slight ergonomic sacrifice is worth the size and weight savings.
Battery Life
I don’t think this should be a knock, but DSLRs have better battery life. I don’t think battery life from mirrorless cameras is necessarily poor, it’s just not as good when compared to DSLRs.
Like I said above, a minor thing unless you find yourself off the grid for long periods of time.