![]() RawDigger is more precise than any exposure meter for the purpose of evaluation of the uniformity of fill light and reproduction light setups (in terms of the evenness of both color balance and luminosity across the background).RawDigger is a useful tool for examining how the relative per-channel underexposure depends on the color of light.If the shadows look blotchy, colorless, or details in shadows are poorly resolved you will be able to determine how much they are underexposed and set Underexposure (UE) indicator in RawDigger accordingly.RawDigger helps determining the raw level at which the overexposure “blinkies” start on the camera LCD and to know how much headroom is still available after the blinkies start showing.For ETTR practitioners, RawDigger makes it very simple to compare raw histogram to in-camera histogram and account for the difference, making the exposures as much “to the right” as possible.That is, RawDigger lets you establish the headroom in highlights and obtain optimal exposures. RawDigger allows determining how exposure meter is calibrated and what raw level corresponds to the midpoint of in-camera histogram.Overexposure (OE) indicator will show you exactly what areas of the shot are blown out and in which color channel(s) it happened (best if used in channel view).RawDigger displays the real histogram of the raw data, which greatly differs from the in-camera histogram and histograms presented by most of the raw convertors.Support for new cameras is usually implemented within few weeks after raw samples become available. RawDigger supports nearly all cameras that have raw capability. Instead, it allows you to see the data that will be used by raw convertors. RawDigger doesn’t alter the raw data in any way. In essence, it is a microscope of sorts that lets you drill down into raw data. ![]() It makes an even stronger case for not explaining photographic concepts to lay people in electronic engineering terms, especially if one gets it wrong.RawDigger by LibRaw, LLC, is a tool to visualize and examine pure raw data as the camera has recorded it. That does not disparage photographers electronics is a profession, like surgery and accounting, and those last two are just as mysterious to me as electronics is to those who have not done electronics design. I fully agree that these concepts are challenging and largely irrelevant to practicing photographers, but the concept and execution of variable signal gain between a sensor and an A/D are basic processes for experienced electronic engineers. Along with it will come misconceptions, such as that so-called 'ISO noise' is cause by 'amplification', which, if you have designed data conversion circuits, you will know is false. People who are not electronic engineers don't know what 'gain' is in any detail, so it's just swapping one unknown concept for another. #Libraw rawdigger isoTo focus on one, which is not universal, and say that ISO 'is' that one, and use it as an explanation, when it is largely irrelevant to what the ISO control actually does is just misleading. The control of ISO includes different operations, very often camera dependent. ![]() Rather, the control of ISO includes a change of gain over some of the ISO range. In any case, CMOS circuits (which these invariably are nowadays) are very high input impedance, so certainly don't need variable current gain to 'match' them It would also be remarkably poor electronic engineering that gave the ADC such a complex input impedance that it required both variable current and voltage gain to drive it. Not just voltage a lot of current gain as well due to the impedance mismatch. ISO control is not 'effected' by a variable 'analog' (actually voltage) stage. I would quibble with the exact choice of words. ![]() I speak as a photographer and also someone who used to design data-conversion circuits. It's a pretty simple concept, and variable gain between a sensor and an A/D is a common circuit in many applications. In most digital cameras, ISO control is effected over most of its range by a variable analog gain stage between the sensor and the A/D. ![]()
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