4 ms·

Two key reasons: 1) m4/3 and similar cameras use EVFs (electronic viewfinders) instead of optical ones - these have inherent and percievable lag. It's getting

Two key reasons: 1) m4/3 and similar cameras use EVFs (electronic viewfinders) instead of optical ones - these have inherent and percievable lag. It's getting better, but still present (and due to the way they work, it's unlikely to be eliminated in the near future). This means that what you see through the viewfinder is a bit behind what's really happening, making precise timing hard. 2) Focussing on fast-moving targets - espcially if the background is "busy" (i.e. has lots of contrast) is very hard for the camera (and user!) to get right. Most non-DSLR cameras use contrast-based autofocus, which is more accurate for still scenes, but slower and worse at dealing with demanding situations like the one I illustrated. DSLRs use phase detection sensors, which are much better at highly demanding situations like these (although slightly less accurate with still subjects). Neither of these means that it's impossible - but it does mean that in situations like the one I described your success rate - shots that are in focus, and where the timing is correct - tends to be significantly lower than with a highend DSLR. When you're trying to capture a rare event (again like the one I described) that you only have one attempt at per day/week/whatever, a significantly reduced success rate is a really big problem.

3chelon 10y ago
The EVF lag is the primary reason I've stuck with DSLR over micro-4/3 until now. Every one I've tried, no matter how fast it's purported to be, has just enough lag to make me feel slightly queasy. Another reason is that the EVF is a screen with all its inherent issues. A screen is its own light source, compared to a DSLR finder which is the sunlight bouncing off the scene via the mirror directly into your eye. Your eye via a mirror can see a much larger dynamic range than the EVF screen, and you can make a call on exposure based on that. That said, if the EVF was truly representative of what the sensor was picking up, it may actually be useful, but the EVF is almost certainly showing a quantized version of what the sensor is seeing, and when you get the image in Lightroom or whatever it'll be different to what you saw on the EVF.
iwintermute 10y ago
RE 2) mirror-less cameras now use hybrid focus - both contrast and phase detection, also they have much more focus points to work with. Plus shooting speed should also be quicker in mirror-less (not sure if super high-end DSLR is still close) - sony a6000 gives you 11 fps of continuous shooting rate
- jfindley 10y ago
  Some of them have started doing this - tech is always marching forward. However no mirrorless system in the world comes close to a highend DSLR. The Sony a6000 is probably the best mirrorless system I'm aware of right now for autofocus, but it still can't come close to what a skilled (for example) Nikon D5 user can do. There are a number of reasons for this, some of which are: 1) One dimensional phase detect sensors, rather than the (more expensive) cross-hatch ones used in DSLRs, which don't perform as well with movement or low light conditions. 2) Reduced processing power, lack of dedicated autofocus processing silicon, and less sophisicated data pipeline in general. 3) Greatly reduced user control. DSLRs, pro ones especially, have enormously sophisiticated control systems, and the ability to completely switch setup very quickly. There are a huge number of ways I can influence what descions the autofocus system makes on my cameras, and I use them to make sure the camera corretly interprets what part of what object it should be focussing on. I probably want the camera to be focussing on the head of the bird (rather than the wingtip, which is typically what a m4/3 system will go for), but that's unlikely to be in the exact centre of the frame, and definitely isn't the closest or most distinct object in the scene, so I need to tell the camera (very quickly and accurately) what it should do. Small mirrorless cameras with limited physical buttons and less tightly controllable focus systems make this very hard. Highend DSLRs can also beat that continuous shooting rate - a Nikon D5, for example, will do 12fps (or 14fps with the mirror locked up). However frames per second isn't always relevent - you're going to be at 1/2000s minimum for this sort of shot, which means that even at 12fps you're capturing only ~ 0.6% of the time. If there's one specific moment you're targetting, even at very high fps, holding the shutter down is a bad strategy. It's useful in some situations (fps is important for pro sports photography for example), but it's often less important than a lot of people seem to believe.
  - CWuestefeld 10y ago
    I shoot with both a Pentax K-30 (a DSLR that you'd classify as pretty decent pro-sumer, but about 3-year-old tech) and an Olympus OM-D E-M5ii (a mirrorless m43 that is one of the best available for this technology - although the Sony has a better sensor). And a caveat to this: I'm a really crappy bird photographer, I do mostly landscape. DSLRs, pro ones especially, have enormously sophisiticated control systems... There are a huge number of ways I can influence what descions the autofocus system makes If anything, the control system in my m43 camera is more sophisticated. And the autofocus is a big part of that. Similar to many cell phones, my m43 camera has a touch screen that allows me to tap the part of the scene I'd like it to use for focusing. This is a better system than any DSLR I've used. I doubt that in autopilot it would pick the wingtip: because it's in motion it's likely to be less sharp than, say, the head. Regarding the lag in the EVF, it's certainly noticeable. But I don't see that as a problem in this use case. My experience with capturing moving subjects is that you don't even try to get that one single perfect shot. Instead you're going to be in high-speed shooting mode, grabbing many images of the scene over at least a second or so, in order to pick the best of the set. In this case, the frame rate really is important. Finally, there's a real advantage to a mirrorless camera for the landscape work I usually do. A lot of the shots I'm looking for are long exposures where it's imperative for the camera to be absolutely still (and I've found that your approach shouldn't be "use a tripod when necessary", but instead "always use a tripod unless it's impractical to do so"). Even the internal operations of the camera can introduce unwanted vibrations. Most DSLRs (unfortunately my DSLR is not one of these) allow you lock up the mirror, which is the largest offender, but that precludes use of the optical viewfinder. But even farther, my mirrorless m43 also allows switching to full-electronic shutter, so there's nothing mechanical at all to shake the camera; I'm not aware of any DSLR that has such a mode, although there may be something out there.
astrostl 10y ago
The http://www.getolympus.com/us/en/e-m1-mark-ii.html http://www.getolympus.com/us/en/e-m1-mark-ii.html is positioned to blow the doors off of this, FWIW
- jfindley 10y ago
  That looks great! I'd love not to have to carry so much weight to carry around with me. I do wonder if it might still struggle to keep up with the controllability of the pro DSLRs, which I discussed in a different reply, but until I can actually try one that's likely to remain an open question.
  - CWuestefeld 10y ago
    I responded to your above comment at [1] to say that I think the controls available in my OM-D E-M5ii are better than my DSLR. And t-he EM1ii will be taking the best parts of the E-M5ii and the E-M1. Basically, my experience is that the control surface of my E-M5ii is superior to that of my DSLR, especially in the area of autofocus. It also has some cool stuff that I've never heard of a DSLR doing. For example, my camera does exposure bracketing by automatically driving the autofocus servos; the E-M1 (and in the future, E-M1ii) take that to automatic in-camera focus stacking. I will say that every manufacturer seems to have a different approach to how their various exposure priority modes trade off. Like when I'm in Aperture priority, how much does it change Shutter vs ISO? I dislike how Olympus does that, and actually think that Pentax's heuristics are the best I've seen. My point, I guess, is that the control systems are always just something you have to learn to work with given the way you think about the camera operation. [1] https://news.ycombinator.com/item?id=12807091 https://news.ycombinator.com/item?id=12807091

3chelon 10y ago

The EVF lag is the primary reason I've stuck with DSLR over micro-4/3 until now. Every one I've tried, no matter how fast it's purported to be, has just enough lag to make me feel slightly queasy. Another reason is that the EVF is a screen with all its inherent issues. A screen is its own light source, compared to a DSLR finder which is the sunlight bouncing off the scene via the mirror directly into your eye. Your eye via a mirror can see a much larger dynamic range than the EVF screen, and you can make a call on exposure based on that. That said, if the EVF was truly representative of what the sensor was picking up, it may actually be useful, but the EVF is almost certainly showing a quantized version of what the sensor is seeing, and when you get the image in Lightroom or whatever it'll be different to what you saw on the EVF.

iwintermute 10y ago

RE 2) mirror-less cameras now use hybrid focus - both contrast and phase detection, also they have much more focus points to work with. Plus shooting speed should also be quicker in mirror-less (not sure if super high-end DSLR is still close) - sony a6000 gives you 11 fps of continuous shooting rate

jfindley 10y ago
Some of them have started doing this - tech is always marching forward. However no mirrorless system in the world comes close to a highend DSLR. The Sony a6000 is probably the best mirrorless system I'm aware of right now for autofocus, but it still can't come close to what a skilled (for example) Nikon D5 user can do. There are a number of reasons for this, some of which are: 1) One dimensional phase detect sensors, rather than the (more expensive) cross-hatch ones used in DSLRs, which don't perform as well with movement or low light conditions. 2) Reduced processing power, lack of dedicated autofocus processing silicon, and less sophisicated data pipeline in general. 3) Greatly reduced user control. DSLRs, pro ones especially, have enormously sophisiticated control systems, and the ability to completely switch setup very quickly. There are a huge number of ways I can influence what descions the autofocus system makes on my cameras, and I use them to make sure the camera corretly interprets what part of what object it should be focussing on. I probably want the camera to be focussing on the head of the bird (rather than the wingtip, which is typically what a m4/3 system will go for), but that's unlikely to be in the exact centre of the frame, and definitely isn't the closest or most distinct object in the scene, so I need to tell the camera (very quickly and accurately) what it should do. Small mirrorless cameras with limited physical buttons and less tightly controllable focus systems make this very hard. Highend DSLRs can also beat that continuous shooting rate - a Nikon D5, for example, will do 12fps (or 14fps with the mirror locked up). However frames per second isn't always relevent - you're going to be at 1/2000s minimum for this sort of shot, which means that even at 12fps you're capturing only ~ 0.6% of the time. If there's one specific moment you're targetting, even at very high fps, holding the shutter down is a bad strategy. It's useful in some situations (fps is important for pro sports photography for example), but it's often less important than a lot of people seem to believe.
- CWuestefeld 10y ago
  I shoot with both a Pentax K-30 (a DSLR that you'd classify as pretty decent pro-sumer, but about 3-year-old tech) and an Olympus OM-D E-M5ii (a mirrorless m43 that is one of the best available for this technology - although the Sony has a better sensor). And a caveat to this: I'm a really crappy bird photographer, I do mostly landscape. DSLRs, pro ones especially, have enormously sophisiticated control systems... There are a huge number of ways I can influence what descions the autofocus system makes If anything, the control system in my m43 camera is more sophisticated. And the autofocus is a big part of that. Similar to many cell phones, my m43 camera has a touch screen that allows me to tap the part of the scene I'd like it to use for focusing. This is a better system than any DSLR I've used. I doubt that in autopilot it would pick the wingtip: because it's in motion it's likely to be less sharp than, say, the head. Regarding the lag in the EVF, it's certainly noticeable. But I don't see that as a problem in this use case. My experience with capturing moving subjects is that you don't even try to get that one single perfect shot. Instead you're going to be in high-speed shooting mode, grabbing many images of the scene over at least a second or so, in order to pick the best of the set. In this case, the frame rate really is important. Finally, there's a real advantage to a mirrorless camera for the landscape work I usually do. A lot of the shots I'm looking for are long exposures where it's imperative for the camera to be absolutely still (and I've found that your approach shouldn't be "use a tripod when necessary", but instead "always use a tripod unless it's impractical to do so"). Even the internal operations of the camera can introduce unwanted vibrations. Most DSLRs (unfortunately my DSLR is not one of these) allow you lock up the mirror, which is the largest offender, but that precludes use of the optical viewfinder. But even farther, my mirrorless m43 also allows switching to full-electronic shutter, so there's nothing mechanical at all to shake the camera; I'm not aware of any DSLR that has such a mode, although there may be something out there.

astrostl 10y ago

The http://www.getolympus.com/us/en/e-m1-mark-ii.html http://www.getolympus.com/us/en/e-m1-mark-ii.html is positioned to blow the doors off of this, FWIW

jfindley 10y ago
That looks great! I'd love not to have to carry so much weight to carry around with me. I do wonder if it might still struggle to keep up with the controllability of the pro DSLRs, which I discussed in a different reply, but until I can actually try one that's likely to remain an open question.
- CWuestefeld 10y ago
  I responded to your above comment at [1] to say that I think the controls available in my OM-D E-M5ii are better than my DSLR. And t-he EM1ii will be taking the best parts of the E-M5ii and the E-M1. Basically, my experience is that the control surface of my E-M5ii is superior to that of my DSLR, especially in the area of autofocus. It also has some cool stuff that I've never heard of a DSLR doing. For example, my camera does exposure bracketing by automatically driving the autofocus servos; the E-M1 (and in the future, E-M1ii) take that to automatic in-camera focus stacking. I will say that every manufacturer seems to have a different approach to how their various exposure priority modes trade off. Like when I'm in Aperture priority, how much does it change Shutter vs ISO? I dislike how Olympus does that, and actually think that Pentax's heuristics are the best I've seen. My point, I guess, is that the control systems are always just something you have to learn to work with given the way you think about the camera operation. [1] https://news.ycombinator.com/item?id=12807091 https://news.ycombinator.com/item?id=12807091