(We're not sure why Imatest sometimes doesn't report DR for the lower quality thresholds like this. In the darkest shadows though, there was indeed some plugging, rather than a smooth trailing-off. There's clearly more gradation at the highlight end of the tonal scale, but examining deep shadows on the D700's test images showed excellent detail, in all but the very darkest shadows. A sharp tail-off at the shadow end usually signals plugged shadows and lost detail in images, but the D700 really didn't seem to show this. The tone curve shows excellent gradation in highlights, but the shadow end trails off more abruptly. These are excellent results for in-camera JPEGs, near the top of the SLRs we've tested. The image below shows the test results from Imatest for an in-camera JPEG file from the Nikon D700 with a nominally-exposed density step target (Stouffer 4110), and the D700's Active D-Lighting and contrast settings at their default positions. For most photographers and most applications, the noise thresholds of 0.5 and 0.25 f-stops are probably the most relevant to the production of acceptable-quality finished images, but many noise-sensitive shooters will insist on the 0.1 f-stop limit for their most critical work. The noise thresholds are specified in terms of f-stops of equivalent luminance variation in the final image file, and dynamic range is computed for noise thresholds of 1.0 (low image quality), 0.5 (medium image quality), 0.25 (medium-high image quality) and 0.1 (high image quality). To this end, Imatest computes a number of different dynamic range measurements, based on a variety of image noise thresholds. What makes most sense then, is to specify useful dynamic range in terms of the point at which image noise reaches some agreed-upon threshold. (Noise will be much more visible in subjects with large areas of flat tints and subtle shading than it would in subjects with strong, highly contrasting surface texture.) This, of course, is a very subjective matter, and will vary with the application and even the subject matter in question. What we care about as photographers is how much detail we can pull out of the shadows before image noise becomes too objectionable. Note the use of the qualifier "useful" in there: While it's tempting to evaluate dynamic range as the maximum number of tonal steps that can be discerned at all, that measure of dynamic range has very little relevance to real-world photography. At the lower end of the tonal scale, dynamic range is determined by the point at which there ceases to be any useful difference between adjacent tonal steps. At the upper end of the tonal scale, dynamic range is dictated by the point at which the RGB data "saturates" at values of 255, 255, 255. Also note that above ISO 6400, the "Off" setting still applies "minimal" noise reduction, explaining why the "Off" and "Low" curves are so close to each other at the highest ISOs.Ī key parameter in a digital camera is its Dynamic Range, the range of brightness that can be faithfully recorded. Note that Hi ISO NR does not apply under ISO 2,000, so the graph starts at ISO 1,600, where the results of the different settings are the same. Usually commercial software or games are produced for sale or to serve a commercial purpose.Here's a plot comparing results using the D700's four High ISO noise reduction settings. Even though, most trial software products are only time-limited some also have feature limitations. After that trial period (usually 15 to 90 days) the user can decide whether to buy the software or not. Trial software allows the user to evaluate the software for a limited amount of time. Demos are usually not time-limited (like Trial software) but the functionality is limited. In some cases, all the functionality is disabled until the license is purchased. Demoĭemo programs have a limited functionality for free, but charge for an advanced set of features or for the removal of advertisements from the program's interfaces. In some cases, ads may be show to the users. Basically, a product is offered Free to Play (Freemium) and the user can decide if he wants to pay the money (Premium) for additional features, services, virtual or physical goods that expand the functionality of the game. This license is commonly used for video games and it allows users to download and play the game for free. There are many different open source licenses but they all must comply with the Open Source Definition - in brief: the software can be freely used, modified and shared. Programs released under this license can be used at no cost for both personal and commercial purposes. Open Source software is software with source code that anyone can inspect, modify or enhance. Freeware products can be used free of charge for both personal and professional (commercial use). Freeware programs can be downloaded used free of charge and without any time limitations.
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