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 p.10 #8 · p.10 #8 · Steve Perry on the Z9 with FW 4.1 - follow up video | |
CanadaMark wrote:
I could see that for Event/PJ work, maybe at the extremely high ISOs like 25,600+ where certain lower MP sensors start to outperform the higher MP ones in terms of normalized noise. Much below that and you aren't gaining anything in terms of noise performance once resolution is normalized. Higher resolution images with finer grain noise also respond better to the NR / RAW converters that so many people use these days. Personally, I prefer the high ISO results from the higher MP sensors when all is said and done, but I very rarely shoot above ISO 25,600.
I've been in situations where I've had to shoot at ISO 102400 to get any image to register, and I was happy to be shooting with a camera that could do that (20 MP D5). But also I find that in figure skating photography, the colours and tonality of the 20 MP Nikons are much nicer than from the Z8, while the latter is capable of more detail, I simply don't like the images as much. It may have to do with the colour of the light sources and how the sensors react to it, or just the noise. Note that in daylight there is a lot more blue in skylight (which is what you have to work with in typical low light situations outdoors before nightfall) and this actually assists the sensors in producing acceptable results in these conditions. The sensors are natively more sensitive to red than blue, and so blue is the noisiest colour channel, but in natural light this doesn't look so bad. In artificial light typically the colour is warmer (low K) and this leaves the sensors with very little to work with to create normal coloured images. In this situation the 20 MP sensors produce nicer results in my experience.
If the sole usage case is sharing highly downsampled images for the web with little to no cropping, you don't need 24MP either, 6-12MP is plenty for that.
That's true but if you need to do a bit of cropping or use also for other applications, 24 MP is a very good compromise. When printed at wall display size (say A3+, A2) I have some that are from 24, some 36, 45 and to be honest I can't tell any difference in most images from distances where the images would be looked at on wall display. If the images are printed large and viewed at reading distance, then I can see a clear difference for up to ISO 1250 or so, where the 45 MP wins, but at higher ISOs such as 12800-25600 in side-by-side comparisons between 45 MP and 20 MP my conclusion is that the 20 MP is actually a bit more detailed and the 45 MP images have shadows that are pitch black, while the 20 MP images still have some tones.
What wildlife photographers tend to prefer the high-resolution sensors because of fur and feather detail but as primarily a people photographer how the skin looks like is a priority for me, and most of my shooting is in artificial light and the 20-24MP sensors are a delight while the Z8's sensor has been a slight disappointment coming even from the similar but not stacked 45 MP. Even in natural light, as the light gets low the images from the 45 MP look "thin" and lacking in richness in tones. It's a bit like images from a slightly underexposed negative.
If you look at news articles and the like, many embedded images are only a few hundred pixels wide, and frankly at that point any modern sensor is going to look about the same. I'm of the opinion that higher resolution only has advantages, all else equal, even if you only benefit from it occasionally. It's better to have than not have in most cases, IMO, especially when there aren't really any downsides outside extreme use cases.
I don't agree; I shot some figure skating a month ago with the Z8 and D6, and the D6 images were edited the same day, while it took me a month to finally get the Z8 images edited because it's such a slow process in comparison. I didn't shoot an equal number of images because I can be more selective when using the optical viewfinder, but the main factor is that on my computer, the HE* images took 8 seconds to move from one image to the next and fully zoomed in (when there are full-size people in the image, I have to see the details of their faces to compare which has the best expression even if the differences are small), while the D6 images were virtually instantaneous to move from one to the next and zoom in, so I could work much faster and there were not these frustrating pauses. The Z8 images shot in lossless compressed NEF were about 4 seconds between zoomed-in consequtive images in a catalog of 15000 images on an USB-connected external SSD; I know it is faster on internal drives but those are too full at the moment (largely due to shooting 45 MP images too much of the time). Overall I find it a much more productive and pleasing experience to work with the 20 MP images in this context. Yes, get a new computer, I bought my computer from options available that will support my LS-9000 (which limited my options); once you have 100 TB of images or more then it gets really expensive to have all that on internal high speed drives. Fortunately I now have Zf so I can shoot lower megapixel files on both mounts. I still prefer the D6 for tough lighting conditions but the Zf files are better at low ISO and because of the in-camera VR I can realistically get good results in low light conditions by risking some subject movement and take more shots than the other option which would be to shoot at a fast speed at very high ISO and get consistent but a bit more noisy images. It's good to have options.
The global shutter is obviously fantastic, hopefully this is just the beginning of that making its way through the industry and I fully expect the few downsides to be overcome.
Global shutter sensors tend to have lower DR and I would be very surprised if Sony had overcome this. A base ISO of 250 suggests they aren't even aiming for high DR. I read that it's not a dual gain sensor; it's interesting to see what kind of image quality they managed to get from that.
Here's the Z9 vs the current crop of 24MP sensor cameras using the "low light" DPR model at 25,600 in the shadows, which is about the upper limit before non-stacked 24MP sensors start to pull away. The only one doing materially better is the Z6II, and I wouldn't be surprised if the Z9 still looked better after processing as downsampling will help out with acutance as well (same reason oversampling improves video quality). Actually that might be a fun experiment as I can download those RAWs.
The Zf has the Z6II's sensor but improved VR and improved AF (and Nikon claims it can focus in lower light), I would consider it ahead of the Z6 II in low light capabilities for those reasons, but I haven't made a side by side comparison because I sold the Z6 II, so I don't have it as a reference.
Comparing the D850 and D5 at ISO 12800-25600 in practical tripod-based comparison led me to believe that the latter actually produces slightly more detailed images, but the difference is slight. Anyway, ultimately image quality depends on conditions, subject matter, and subjective criteria, and different photographers may come to different conclusions. For me it's how the skin tones look like which is the main criteria for image quality under these conditions. If shooting in a studio, I'll happily take the ISO 64 images from the 45 MP sensor, and do.
If you use dpreview's studio comparison tool, select incandescent light (the bulb icon near the top right corner) to get to see how the results look like in artificial light. Click "print" to compare equal size parts of the images side by side. Go to an area which has dark blue subject matter, such as the color wheel at 1/3 from the left, 1/6 from the bottom. To my eye the noise in the 45 MP Z8 is quite gross in there. The Z6 II gives a bit better in detail than the D5 because they use a better (and twice as expensive) lens on the Z camera and probably the Z6 II has a thinner, apparently one-directional AA filter instead of two-directional.
Anyway, to my eye the Z8's images are already lacking at around ISO 2000-3200 in artificial light, while in natural light it is excellent up to about 1250 ISO and usable up to ISO 6400. However, given the 8 s vs. 1 s image switch time (granted, specific to external drive on my computer, but it is what I have to work with until I can clean up some space on internal drives), I would reserve the use of that camera to lower ISOs where the benefits in image detail are more obvious and tonality still good because I don't want to spend my life waiting. Yes, I could update my computer more frequently but with the amount of internal storage that I have, I'd prefer to get some years from my current one still. It's quite fast when I don't have to resort to external storage, and when using the lossless compressed NEF. But my drives always tend to fill up with new material and any new computer slows down when it's filled to the hilt. Working with the 20-24 MP files is practical and a delight in comparison, and a happy photographer can and will spend more time shooting. My experience is that in order to get a material benefit (one that is obvious) one really needs to max out at ISO 1250 or so, at which point one can take advantage of the higher potential for image quality of the 45 MP sensor and there is real detail that is not obfuscated by the noise, and even a cropped image can print with high quality. At up to ISO 1250 even I don't have no objections and consider the 45 MP sensors to produce superior results that may make the storage and processing delays somewhat worthwhile, if one aims for printing and does not shoot that many images in low light.
Howeve, the majority of people don't seem to print any more (as per their own announcement, many even ridiculing the idea of printing), and social media barely needs more than a FullHD sized image, which makes me wonder what the purpose of the enthusiasm for the high-resolution sensors is coming from.
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). If there is an empty background then this doesn't happen but then the images lack the feel of audience support. I'm probably happier working in single shot mode for the most part because that way I get a high rate of keepers (and shots with clear intention) even if some moments are hard to catch. I will use previews the next time to see what that does to the editing experience. (I have used them sometimes in the past but being tight on storage often discourages me from generating them.)