60 DIGITAL CAMERA^ APRIL 2020 http://www.digitalcameraworld.com
CAMERA COLLEGEshake reduction in the camera’s electronic
viewfinder. The chief advantage of IBIS is
that it offers the potential for stabilising the
image produced by a lens that doesn’t have
a built-in stabiliser. Non-stabilised lenses
are generally less complex, less heavy
and less expensive than their stabilised
counterparts. What’s more, only the
camera body would need to be upgraded to
take advantage of any new advancements
in stabilisation, compared with the cost
that comes with having to upgrade a
whole set of stabilised lenses over time.
If IBIS has a drawback, it is that it is the
general all-rounder of the stabilisation
world. Unlike a lens-based system, where
the stabiliser can be optimised for a specific
focal length or zoom range, IBIS is prettymuch a ‘one size fits all’ solution. Longer
lenses require more substantial correction
than shorter ones, for example, and a
lens-based system performs better in this
regard – there’s a reason why Sony, which
uses IBIS in many of its cameras, still
includes stabilisers in its telephoto lenses.
Some camera manufacturers use a
combination of image-stabilised lenses
and IBIS to achieve an enhanced level
of camera shake compensation.
Finally, there’s electronic stabilisation.
Often used for movie recording, this doesn’t
require any moving parts, but uses spare
pixels on the camera’s sensor to keep the
image in the same position as the camera
moves. As a result, there is inevitably some
loss of resolution and image quality.Longer lenses require more
substantial correction than
shorter ones, for example,
and a lens-based system
performs betterWhat is electronic stabilisation?
If you’re shooting video, you might benefit from reducing the shakes digitally
Electronic image stabilisation is
where vibrations are counteracted
using software rather than physically
moving internal parts of the lens or
camera. It’s typically used for movie
recording rather than stills shooting,
as the process requires the sacrifice of
some pixels – something that’s relatively
straightforward when today’s ultra-high-resolution cameras actually have
too many pixels for movies. It also
doesn’t generate any audible noise,
unlike lens stabilisation.
Achieving electronic stabilisation
requires the image to be digitally cropped
a little, with the spare pixels allowing each
frame to be repositioned and aligned on
the sensor in order to keep the footagestable. This technique can also be used
during the post-production of movies,
where the resolution of clips can be
reduced in order to reframe the shot.
The drawbacks to stabilising the image
digitally are that you have to consider
your initial framing carefully and you lose
some image quality, although the benefit
of stable footage usually outweighs this.Gimbals
If you’re serious about
shooting video, you’ll
probably reach for a
gimbal, such as the DJI
Ronin SC (above), instead
of using any form of in-
camera stabilisation. These
devices provide a smoother
form of stabilisation that’s
better if you’re making
large movements with the
camera rather than trying
to keep it stock still.Cropped image
With electronic stabilisation technology, the image ends up being cropped to achieve the steady image –
sometimes quite substantially if you’re doing stabilising in ‘post’ – so it’s more widely used in video.DJI