![]() ![]() ![]() Positive values result in brighter default results, while negative values result in darker default results.Īdobe DNG Specification p.38, Version 1.4.0.0, June 2012 BaselineExposure specifies by how much (in EV units) to move the zero point. This allows for less negative exposure compensation, but results in lower shadow noise for normal exposures.īecause of these differences, a raw converter needs to vary the zero point of its exposure compensation control from model to model. Other models leave less headroom during normal exposures. This allows significant negative exposure compensation to be applied during raw conversion, but also means normal exposures will contain more shadow noise. Some leave a significant amount of highlight headroom during a normal exposure. Let’s start with the problem Baseline Exposure is trying to address:Ĭamera models vary in the trade-off they make between highlight headroom and shadow noise. 1) How to Find the Value for Baseline Exposure (BLE)? Now, we are ready to find out the value of that important ingredient in Adobe’s hidden corrections recipe, the Baseline Exposure. Save the resulting settings and name them (optionally, you can set them as defaults).We didn’t show how to find Baseline Exposure for your camera(s), but for the purposes of the demonstration we used 0.25, since it is Nikon Df’s Baseline Exposure for the ISO we used to make the shots for the experiments Subtract Baseline Exposure compensation (BLE) from Exposure, so that now Exposure = -1-BLE.Custom Curve (the converter, be it ACR or Lr, will automatically calculate it for you when switching from PV2010 to PV2012).For Adobe raw converters, the zeroed-out PV2012 (without accounting for Baseline Exposure compensation) has the following settings: ![]() We demonstrated in the previous article that the brightness is now in “repro”, linear mode, except for Baseline Exposure. Switch back to Process Version 2012 (PV2012) now all of the settings are changed automatically and they replicate the “look of brightness” of the image you previously had in PV2010.Set the black point, the contrast, and the brightness all to zero.Switch to Process Version 2010 (PV2010) and.The algorithm was pretty straightforward: In the previous article, we demonstrated how to linearize (to zero out) the default settings in an Adobe raw converter, or in other words, how to override Adobe’s hidden corrections to contrast, brightness, black level, and tone curve ( actually, in film terms, all of the above is characteristic curve). That hidden exposure compensation is the exact amount you can pull the exposure slider to get the highlights back, before the software resorts to interpolation to guess what was in the blown-out highlights. The first one is to improve exposure practice the second is to determine which highlights can be brought back safely. There are at least two practical reasons to investigate hidden exposure compensation in raw converters. We will be dealing in depth with Adobe’s converters, but the same method stands for any other converter. The goal of this article is to demonstrate how you can find the hidden exposure compensation your converter is applying to your raw files when opening them. Even avid Exposing To The Right (ETTR) practitioners can get into this trap, as they consider a histogram derived from the in-camera beautified conversion to be an indication of exposure. In fact, the shot may be underexposed, sometimes by more than 1 stop, and the price is more noise, more artifacts, less resolution, and, ultimately, getting a new camera, which doesn’t really solve the problem. It often leaves a false impression of properly exposed raw, as we are so accustomed to mixing up exposure and brightness, judging former by the latter. The brightening of the mid-tones that is done behind the scenes is one of the most common approaches to add punch to a raw image. If you are using or planning to use some raw converter, you may want to know what “beautifiers” it applies, and their price. This is done to make the shot look good, but can also lead to all sorts of confusion. As we already mentioned in the previous article “ Where are my Mid-tones?“, most raw converters apply some hidden adjustments to a raw shot, often resulting in a bumped mid-tone, clipped highlights, and compressed shadows. ![]()
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