![]() What pleases me with my current Nikon cameras, both D800E and D7100, is that one can easily separate exposure and focusing by pressing the appropriate buttons whilst the camera viewfinder is still held to eye. Maybe later models now have this feature. I would have preferred to have been able to bracket ISO in such circumstances, but my Canon cameras did not have this facility. This was not entirely satisfactory because sometimes the greatest exposure (the slowest shutter speed) which produced the most accurate ETTR shot, was too slow for a sharp image when the camera was hand-held, and/or when the subject was not perfectly stationary. What I used to do, when shooting with Canon DSLRs, was frequently bracket exposure at a fixed aperture. This is not something I've experimented with, so far. One can keep the shutter speed constant and bracket aperture if DoF is not an issue. Choosing the appropriate aperture first to achieve the desired DoF usually applies, although it doesn't have to apply. The difficulties occur when the camera is hand-held. One simply brackets exposure with mirror up. If one is shooting a static scene with camera on tripod, there should be no problem at all. Perhaps what is lacking in the current trend of this thread towards the minutiae of ETTR precision, is advice on the practicalities of achieving the desired ETTR exposure in the field, in a manner which allows one to get the shot, or capture the moment. Some clipping is unavoidable with these transformations. Screen captures from a WideGamut monitor, with image assigned Monitor profile and then converted to sRGB for web viewing. This could cause hue shifts and it is not clear if the increased SNR would be worth it in terms of SNR and color accuracy.Īnd the ACR histograms without exposure adjustment. One would likely use negative exposure compensation in ACR for the ETTR image. However, the UNIWB image can be rendered into ProPhotoRGB by ACR with no clipping. The UNWB histogram shows clipping on the camera histogram, since AdobeRGB can not accommodate the camera gamut at this exposure level. Giving 2EV more exposure moves the RawDigger two stops to the right and near saturation (a good ETTR exposure). ![]() Note that the red is no longer blown, similar to what was seen in the camera histogram. ![]() Note that the AdobeRGB rendering shows red channel clipping similar to that shown in the camera histogram.Īnd the ACR Adobe RGB histogram for the UNIWB shot at the metered exposure. Here are the ACR histograms for AdobeRGB and ProPhotoRGB for the sunlight WB. The UNIWB preview gives a better preview and shows no clipping, contrary to the Sunlight WB The red channel is blown in the camera histogram, but is 2 EV below clipping in RawDigger. This image shows nominal exposure histograms by the camera and RawDigger (with the green channels averaged) at daylight WB and at UNIWB. The camera was set to AbobeRGB and the standard picture control was chose. Such a feature is one thing that I find myself wanting to more easily determine.Īlso, if such a user-settable threshold-level (only when set by the user) constituted the Maximum reported level in the displayed image statistics, and the Average and Standard Deviation reflected image statistics (only) below that threshold-level, the user would have useful data relating to the image statistics existing in image areas where individual photo-site data does not exceed such a user-settable threshold-level.I've conducted some experiments with daylight illumination (actually 3200K + 80a filter) with the D800e using normal white balance and UNIWB and comparing the camera histogram to the raw histogram as shown by RawDigger. When I see specular highlights appearing in the "raw" image-file's histogram display above some particular level, it occurs to me that it would be very helpful and extremely useful for the user to be to set a threshold-level (in the Histogram window, or in the Main window) where all individual photo-site data (as viewed individually, or as viewed in 2x2 format) above that threshold-level would blink on and off in the Main window display of the image - in a manner similar to that provided in some digital camera preview/review displays. ![]()
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