I have been taking bracketed set for a long time,
particularly I am not certain of the lighting conditions will be interpreted by
the cameras light meter. Cases such as sunrise, sunset, strong contrast/shadows
are good examples. Even if the exposure is off by also taking a couple of extra
photos with a little extra and less
exposure (which is easy on digital cameras) you then have a reduced the risk of
missing a good opportunity. Most digital cameras let you do this by changing
the EV (Exposure Value) sometimes called the exposure compensation. This is a
much simpler number to understand that the interrelation of lens aperture (f-stop)
and exposure time (speed). Each unit of EV is equivalent to doubling the light
(or in simple terms one f-stop). The EV setting on most cameras are relative to
the exposure selected, so +EVs increase the light that lands on the sensor (over
exposes) and negative –EVs decrease the light that lands on the sensor
(underexposes). This is done by the camera either changing the f-stop and/or
speed.
You will probably have to read your camera manual but it is relatively
easy to set up most DSLR to automatically taken an appropriate EV set. For
example I have my Pentax ‘s User mode set up to take a set of 5 images at steps
of 0.5 EV from -1 to +1 EV. I press the shutter … click, click, click, click
& click … I get the exposure in pretty rapid fire (depending on the speed
of the exposure). By having this already programmed there in user mode I just
have to turn the mode dial and press the shutter. It’s very convenient and a
good way to quickly fill memory cards but it bring me comfort that I will get
at least one half decent exposure. On my Canon I tend to just set it up manually
and typically just do 3 photo -1EV, 0EV and +1EV. This is a little more work
but I tend to go for my Pentax when it is an important subject.
Now the selection of the best exposure and whether you want
to post processing the set as HDR can come later. Even though I am now quiet at
ease with the HDR process it still takes time and I have to jump back and forth
between programs so I tend to only do a few HDR photos at any time (a lot of
the sets just remain unprocessed). That is where a minor side benefit of google+
auto backup comes into play. As it is busily (ok its slowish but I’m not
complaining) uploading my old images it tries to run HDR on any suitable sets
it finds (it doesn’t do everything, but it does look at many more than I did)
and each day I seem to get a new notification of new auto awesomes to look at.
I have taken a renewed interest it those it has chosen to do as HDR. Not all
are good, but they have been worth a look, perhaps the better ones will be
worth a second look and perhaps revisiting the post processing that could be
done. I’m not ready to hand over the care and refinement of my photos to an anonymous
algorithm quiet yet, but I am keenly interested it what it can do with my
photos.
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