Capturing backlit subjects, especially those with rim light always fascinate photo-enthusiasts, but at times photographs of subjects like birds requiring details disappoint photographers because despite their best camera settings they get objects like dark patches against bright background. Similar is the case of shooting birds in flight or against bright sky. Some photographers try to resolve these challenging issues by altering their camera settings. They either change ISO sensitivity, shutter speed or aperture and there are others who blame their equipment for poor performance. There are many others who do not find it necessary to go through the camera manual.
Although exposure is an issue of personal choice yet the bird photographers are advised to shoot birds with sun to their back. This is a good suggestion, but the fascination for backlit subjects inspires them to continue experimentation with their gear. The solution to this challenging situation of shooting against bright light lies within their camera. When we set exposure (a combination of Aperture, Shutter Speed and ISO Sensitivity), camera evaluates whole of the frame and we get its average. In fact, we do not always need metering for whole frame. That’s why the camera manufacturers have devised different settings for metering. Therefore, often spot metering is recommended to shoot birds against bright light and centre weighted metering for birds in flight. Also, Auto Exposure Lock (AEL) can help in controlling the variation in exposure, especially when we have to shoot birds against bright sky. The AEL can be used while reframing the image and prevent the current exposure from changing. Each metering mode has its specific functions.The choice for any of the above mentioned measures depends on one’s liking and intensity of available light.
Apart from this, the challenging situation can easily be dealt with a small button bearing EV +/- (Exposure Value ) and generally designed on top or the camera. Its commonly known as Exposure Compensation. This small feature has the ability to override the camera settings of semi-auto exposure modes, like Aperture Priority, Shutter Priority or Programme. In simple words, EV +/- is used to alter exposure so as to make photographs brighter or darker. Its not necessary that by setting exposure we shall get desired result. Therefore, exposure compensation plays a vital role in further guiding the camera in meeting requirement of a photographer.
In case of Aperture Priority mode we select aperture of our choice, but camera automatically sets shutter speed. When we change exposure value in this mode, it automatically changes shutter speed. Similarly, in Shutter Priority mode, we set shutter speed of our choice and exposure compensation automatically changes aperture. In manual mode its entirely up to the photographer to set exposure and in Auto Mode exposure is set by camera itself. The EV does not function in full Auto and Manual shooting modes. In Programme mode, it depends on camera to either change aperture or shutter speed so as to give us desired result. Therefore, the significance of exposure compensation cannot be ignored and it should be used wherever required to get exposure of our choice.
Those who take photographs with Digital Single Lens Reflex (DSLR) cameras, can immediately check the results in camera monitor after taking a test shot and set the exposure value, if required. On the other hand, those who shoot with mirror less cameras, have the distinct advantage to directly set the desired exposure value without reviewing any test shot in the monitor. As we compose the image and increase or decrease the exposure value, the preview in the monitor enables us to see the changing brightness or darkness and how would be the final image.
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