Chụp lấy nét tự động trên Nikon D850 không tốt bằng D5. Những bài đánh giá thực tế luôn làm sáng tỏ nhiều điều thường được các hãng “phóng đại” quá mức khi ra mắt sản phẩm mới. Và bài kiểm tra mới nhất giữa Nikon D850 và D5 một lần nữa minh chứng điều này. Show
Nikon từng quảng cáo D850 có khả năng theo dõi chuyển động và lấy nét nhanh tương đương với D5. Vậy thực tế một model giá 3.300 USD liệu có thể “sánh ngang” với siêu phẩm D5 cao cấp giá 6.500 USD? Theo Petapixel, nhiếp ảnh gia Matt Granger đã quyết định thực hiện một số bài thử nghiệm để đánh giá khả năng theo dõi chuyển động và tự động lấy nét của hai mẫu D850 và D5. Granger khẳng định đã thiết lập cả hai model với cùng thông số giống nhau, ví dụ chụp 7 khung hình/giây. Trong bài thử nghiệm đầu tiên, Granger thử chụp trong điều kiện ánh sáng yếu (ISO được đẩy lên khá cao, dao động từ 1000 trở lên) của studio. Người mẫu thực hiện một số động tác đá và xoay người để thử khả năng theo dõi chuyển động và bắt nét. Cả hai máy đều có hai lần thử. Trong khi D5 có thể bắt và khóa nét thành công, D850 chỉ kịp bắt nét trong lần thử đầu tiên. D5 theo dõi chuyển động và bắt nét khá nhanh. Độ trễ khi theo dõi chuyển động của D850 vẫn còn khá lớn so với D5. Thử nghiệm khi chụp ở ngoài trời thậm chí cho thấy sự khác biệt rõ rệt hơn. Khi người mẫu chạy thẳng về phía camera, D850 chỉ bắt nét được khoảng 60%. Trái ngược lại, D5 có thể bắt nét chính xác chuyển động lên tới 80-90% khung hình. Ngay cả khi chuyển sang dạng chuyển động zig-zag, D5 có thể đạt tỷ lệ bắt nét thành công lên tới 100%. D850 ngược lại vẫn mất khá nhiều thời gian để kịp bắt nét các chuyển động, thậm chí bị out nét khá nhiều. Granger chia sẻ, D850 có thể theo dõi chuyển động hiệu quả trong điều kiện ánh sáng tốt nhưng khi gặp nguồn sáng phức tạp, máy khó có thể bắt nét kịp chủ thể. Điều này trên D5 dường như không phải là vấn đề quá lớn. The Nikon D850 is Nikon's latest high resolution full-frame DSLR, boasting a 46MP backside-illuminated CMOS sensor. But, in a fairly radical departure for the series, it is also one of the company's fastest-shooting DSLRs. This combination of properties should significantly widen the camera's appeal to high-end enthusiasts as well as a broad range of professional photographers. Key Specifications:
High resolutionThe use of a backside illuminated (BSI) sensor means that the light collecting elements of the sensor are closer to the surface of the chip. This should not only increase the efficiency of the sensor (improving low light performance) but should also be expected to make the pixels near the edges of the sensor better able to accept light approaching with high angles of incidence, improving peripheral image quality. Like the D810 before it, the D850 continues to offer an ISO 64 mode, that allows it to tolerate more light in bright conditions. The D850 promises the same dynamic range advantage as the D810, meaning it should be able to compete with the medium format sensors used in the likes of the . The D850 has gained a more usable electronic front curtain shutter option (EFCS), which can now be used quiet shutter modes, as well as live view and Mirror-Up mode. To get the full benefit, though, you need to turn on exposure delay (which has had two sub-second delay settings added). However, exposure delay persists across all shooting modes. Thankfully, and presumably thanks to a redesigned shutter and mirror mechanism, mirror/shutter shock doesn't seem to be much of an issue, even without engaging EFCS. The D850 has no anti-aliasing filter, which should allow for slightly finer detail capture but with added risk of moiré, if any of your lenses are sharp enough to out-resolve a 45.7MP full-frame sensor. There's still no sign of the clever design Nikon patented so, unlike the Pentax K-1 or Sony RX1R II, you can't engage an anti-aliasing effect if you do find false color appearing in densely patterned areas. High SpeedIn addition to the increased speed, the D850 also gains the full AF capabilities of the company's flagship sports camera: the D5. This includes all the hardware: AF module, metering sensor and dedicated AF processor, as well as the full range of AF modes and configuration options, which should translate to comparable focus performance combined with high resolution. Given the D5 possessed one of the best AF systems we've ever seen and could continue to offer that performance in a wide range of conditions and shooting scenarios with minimal need for configuration, this is an exciting prospect. As part of this system, the D850 gains the automated system for setting an AF Fine Tune value. It only calibrates the lens based on the central AF point and for a single distance, but it's a simple way to ensure you're getting closer to your lenses' full capabilities, which is handy given you'll now be able to scrutinize their performance with 46MP of detail. Impressively, the D850 can shoot at nine frames per second if you add the optional MB-D18 battery grip and buy an EN-EL18b battery, as used in the D5. As well as increasing the camera's burst rate, this combination also ups the battery life to a staggering 5140 shots per charge. You don't get this same boost in speed or endurance if you use a second EN-EL15a in the grip, though. An MB-D18 plus an EN-EL18b is likely to set you back over $580 over and above the cost of the camera body ($399 for the grip, around $149 for the battery, $30 for the BL-6 battery chamber cover plus the cost of a charger). The D850 also includes a sufficiently deep buffer to allow fifty-one 14-bit losslessly compressed Raw files, meaning the majority of photographers are unlikely to hit its limits. Video capabilitiesIn terms of video the D850 becomes the first Nikon DSLR to capture 4K video from the full width of its sensor. The camera can shoot at 30, 25 or 24p, at a bitrate of around 144 Mbps. It can simultaneously output uncompressed 4:2:2 8-bit UHD to an external recorder while recording to the card. The camera subsamples to capture its video, lowering the level of detail capture and increasing the risk of moiré, along with a theoretical reduction in low light performance. We'll look at how significant this impact is, later in the review. At 1080 resolution, the camera can shoot at up to 60p, with a slow-mo mode that can capture at 120 frames per second before outputting at 30, 25 or 24p. The 1080 mode also offers focus peaking and digital stabilization, neither of which are available for 4K shooting. The D850 doesn't have any Log gamma options for high-end videographers, but it does have the 'Flat' Picture Profile to squeeze a little extra dynamic range into its footage, without adding too much to the complexity of grading. It also offers full Auto ISO with exposure compensation when shooting in manual exposure mode, meaning you can set your aperture value and shutter speed, and let the camera try to maintain that brightness by varying the sensitivity. As you'd expect from a camera at this level, the D850 also includes the Power Aperture feature that allows the camera to open and close the lens iris smoothly when in live view mode. There's also an 'Attenuator' mode for the camera's audio capture, that rolls-off any loud noises to avoid unpleasant clipping sounds. You may also likeMore about gear in this articleWe've taken a look back at our year of Instagram posts to the @DPReview account and compiled the 10 most popular cameras of 2020, based on most 'likes' to a single post. Take an inside look at the work that goes into testing Nikon cameras from drops, dust, water and debris. There were definitely cameras harmed in the making of this video. A teardown of a Nikon D850 has provided proof that the camera's sensor is made by Sony Semiconductor. The chip's design and performance already strongly supported this, but the confirmation also gives a hint about how the industry works. Award-winning wildlife photographer Roie Galitz shares his experience shooting polar bears with the new Nikon 180-400mm F4E TC1.4 FL ED VR in one of the harshest places on Earth. Find out why Galitz calls his $12,000 behemoth "a dream lens." Nikon looks to be positioning its D850 as a serious video rig with today's announcement of its D850 Filmmaker's Kit. The kit includes the body, 20/35/85mm F1.8G lenses, an Atomos Ninja Flame external recorder, two microphones and an extra battery. Latest sample galleriesLatest in-depth reviewsThe Fujifilm X100VI is the sixth iteration of Fujifilm's classically-styled large sensor compact. A 40MP X-Trans sensor, in-body stabilization and 6.2K video are among the updates. The Nikon Zf is a 24MP full-frame mirrorless camera with classic looks that brings significant improvements to Nikon's mid-price cameras. We just shot a sample reel to get a better feel for its video features and have added our impressions to the review. This $250 electronic lens adapter is perfect for Nikon Z-mount curious Sony shooters — shhh, we won’t tell anyone. Sony updates the ZV-1, giving the vlog-centric compact camera a 18-50mm equivalent F1.8-4.0 lens that's now wide enough for less cramped selfie mode videos. OM Digital Solutions has updated its flagship high speed camera just two years after launch. The latest version includes more memory and some performance and handling tweaks. Latest buying guidesIf you want a compact camera that produces great quality photos without the hassle of changing lenses, there are plenty of choices available for every budget. Read on to find out which portable enthusiast compacts are our favorites. What's the best camera for travel? Good travel cameras should be small, versatile, and offer good image quality. In this buying guide we've rounded-up several great cameras for travel and recommended the best. 'What's the best mirrorless camera?' We're glad you asked. What’s the best camera for around $2000? This price point gives you access to some of the most all-round capable cameras available. Excellent image quality, powerful autofocus and great looking video are the least you can expect. We've picked the models that really stand out. Above $2500 cameras tend to become increasingly specialized, making it difficult to select a 'best' option. We case our eye over the options costing more than $2500 but less than $4000, to find the best all-rounder. |
