![]() I can also change the order of these two processes. ![]() After achieving the optimal exposure setting, I can then move the focusing square to the part of the scene that I want to be in precise focus, and whilst still keeping the shutter button half depressed, press the AF-ON button, recompose the scene and take the shot. With forefinger half depressing the shutter button, I can easily change the shutter speed by turning the wheel with my thumb, until the exposure gauge at the foot of the viewfinder looks right for an ETTR. If I want to expose for the sky, I can move the camera, and/or focusing square in the viewfinder, till the focusing square covers the brightest part of the scene that I consider merits an ETTR. Or perhaps it was possible but I never discovered or realised that it was.Įssentially, with my Nikon cameras, using a single focusing square with camera in manual mode, I can assign focusing to the AF-ON button, and exposure to the half-pressed shutter button. Thus there is no need for any bracketing, unless the scene is so contrasty that one chooses to take different exposures in order to merge to HDR.Īgain, this procedure was not possible with my Canon cameras (the latest was the 50D). 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. 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.
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