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.
--Subhash Sapru
Hon Excellence USPA, APSA, PPSA, AIIPC
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