rhawidantas wrote:
I agree partially; the R2 update from R1 was impressive but R3 is where everything became well rounded. Bigger battery, 14 bit silent shutter, evf, dual card slots, time lapse.
And you mention no revolution but the A1 is one of me most impressive cameras in the last few years.
The a7iv is fine, I would even say great. The issue is that the prices are increasing so much (for everything) that makes me wonder which beginner is going to jump on such a camera.
Anyway, I'm more interested in a a7c2. So, Sony, bring all of these updates plus better evf and front dial to it....Show more →
The 7R3 was better in almost every way, however, it didn't output better images and while it was faster with longer battery life, it was actually slower in a couple of ways, especially since it lost Smooth Reflections.
Both are great, better than offerings from the other makers, but the 7R2 in historical terms will be the one camera in the alpha range that was the most amazing release.
What's more, it's still available new and it's cheap! AUD1400 (USD$1K).
Back on the A74, I've heard the video is quite delicious. It must be the 6K to 4K down-sampling that is delivering some detail which is apparently scrumptious.
So I may eat my words about its video once I get my hands on one soon.
People ale already calling A7C - mini A9 when it comes to AF, so I think A7IV will be great in AF department. It's only when you track a dynamically moving target that it will fall visibly behind imho.
Bob_S wrote:
Both are great, better than offerings from the other makers, but the 7R2 in historical terms will be the one camera in the alpha range that was the most amazing release.
Pixel Perfect wrote:
That's the trouble with keeping such a poor scan speed, you cannot do 60 AF calucaltions a second from a sensor that at best does 1/20s scan speed.
You could, since you would not have to read the entire sensor to track something. I'm not sure Sony is currently using that kind of optimization, though.
Steve Spencer wrote:
All this is true, but getting data off the sensor is a clear bottle neck that can affect the AF. The relatively slow sensor scan speed of the A7 IV will impact AF, to what extent and in what situations we will have to wait until people get the camera in their hands to figure that out.
True. However, does the whole sensor need to be read out for AF information, I am not sure? Now with strong processors and pattern recognition in summary with AF modes+RGB sensor information, I can easily imagine the AF system reading out selective information or regions only, speeding things up.
Daran wrote:
You could, since you would not have to read the entire sensor to track something. I'm not sure Sony is currently using that kind of optimization, though.
Exactly, just read that you were thinking about the same thing when I submitted my post.
Holger wrote:
True. However, does the whole sensor need to be read out for AF information, I am not sure? Now with strong processors and pattern recognition in summary with AF modes+RGB sensor information, I can easily imagine the AF system reading out selective information or regions only, speeding things up.
Exmor sensors have per-line readout, so only the lines with PDAF pixels need to be read out for AF.
Oct 23, 2021 at 08:16 AM
Steve Spencer Offline • • • • • • • Upload & Sell: Off
mawz wrote:
Exmor sensors have per-line readout, so only the lines with PDAF pixels need to be read out for AF.
That is true but true for both stacked and unstacked sensors, so scan of those lines with PDAF pixels is still going to be much slower with unstacked sensor and is going to represent a bottle neck for the unstacked sensor,
The benefits of the a7 IV’s top-tier processor become especially impressive when considering the AF capabilities of this camera. Real-time Tracking locks on and keeps pace with fast-moving subjects, thanks to Sony’s latest subject recognition algorithm, which uses color, pattern, and subject distance to process spatial information at lightning-fast speeds. Sticking true to the all-around appeal of this camera, Real-time Eye-AF for humans, animals, and birds are all included to help lock focus across subject types. The a7 IV even quickly re-detects a subject’s eye after it has left and returned to the camera’s frame. Matching the Alpha 1’s 759 phase-detection AF points, the a7 IV boasts 94% image-area coverage to keep subjects in focus regardless of where they are in the scene.
This is something new under the hood is this new recognition algorithm. Sounds interesting
Notice the 759 phase-detection. I think thats the most yet
The benefits of the a7 IV’s top-tier processor become especially impressive when considering the AF capabilities of this camera. Real-time Tracking locks on and keeps pace with fast-moving subjects, thanks to Sony’s latest subject recognition algorithm, which uses color, pattern, and subject distance to process spatial information at lightning-fast speeds. Sticking true to the all-around appeal of this camera, Real-time Eye-AF for humans, animals, and birds are all included to help lock focus across subject types. The a7 IV even quickly re-detects a subject’s eye after it has left and returned to the camera’s frame. Matching the Alpha 1’s 759 phase-detection AF points, the a7 IV boasts 94% image-area coverage to keep subjects in focus regardless of where they are in the scene.
This is something new under the hood is this new recognition algorithm. Sounds interesting
Notice the 759 phase-detection. I think thats the most yet
Steve Spencer wrote:
That is true but true for both stacked and unstacked sensors, so scan of those lines with PDAF pixels is still going to be much slower with unstacked sensor and is going to represent a bottle neck for the unstacked sensor,
Since only a small fraction of lines (AFAIR less than 1 in 20) contain PDAF data, that could be fast enough either way, as long as you only look at PDAF. So even if the full sensor is read at only 1/20s, PDAF only AF could be implemented at >400cps.
Of course for the generally more useful RTT you also need a big chunk of the image in order to detect the pattern. That would remain much faster for stacked sensors.
Oct 23, 2021 at 11:46 AM
Steve Spencer Offline • • • • • • • Upload & Sell: Off
Daran wrote:
Since only a small fraction of lines (AFAIR less than 1 in 20) contain PDAF data, that could be fast enough either way, as long as you only look at PDAF. So even if the full sensor is read at only 1/20s, PDAF only AF could be implemented at >400cps.
Of course for the generally more useful RTT you also need a big chunk of the image in order to detect the pattern. That would remain much faster for stacked sensors.
Yes, it is part of the limitation. If you go PDAF only you can go faster, but you can't use the new fancy algorithms. As Guy was saying the new algorithms are an exciting part of this camera, but they will be limited by the scan speed of the sensor. What you need is fast scan speed and the new algorithms, but you only get that in the A1. This camera will be an improvement over the A7 III and certainly over the A7r IV as well, but won't be anything like the A1. Will it be on par with the A9 (II) maybe in a few ways (and it might even be better in let's say low light), but I am betting the A9 (II) will still be clearly superior in most ways, but that is just a bet. The proof will be in the pudding when we see how the camera actually performs.
I only shoot weddings so the A9/A7III combo works fine for me. There’s no need for me to dole out thousands for a new camera only to take the same pictures.
Talk is getting too technical for my brain.
Soon as arbitrage posts some a7IV 80-120 image burst sequences of BIF, with very high AF keeper rate, I’ll know what I need to know.
Fuji is about to have a 30-34mp X-H2 too (but APSC)…will be curious to see if it becomes competitive in the same space. Their cams are always great for video.
Atlasman2 wrote:
Clever of Sony to bump up the sensor resolution to 33MP—makes Canon's R6 with 20MP less attractive.
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