What is a tilt-shift lens?
It’s a specialist lens that alters
the angle and position of the
lens mechanism in relation to the
camera’s sensor. In a normal lens,
the plane of focus is parallel to the
sensor, but a tilt-shift lens allows
you to change it. The change of the
lens angle in relation to the image
plane is the tilt, while the movement
of the lens parallel to the image
plane is the shift.What’s it used for?
A tilt-shift lens is traditionally used
by architectural photographers
because it allows you to avoid the
distortion of converging verticals
that typically occur when shooting
tall buildings. However, it’s also
used purely for creative effects by
photographers wanting to create
an interesting dynamic in landscapephotography by blurring areas and
switching the plane of focus. A tilt-
shift lens is particularly known for
its ability to create a miniature
‘toytown’ look in a scene when
it’s photographed from above.Is it easy to use?
A tilt-shift lens gives you additional
controls over a normal lens, so it
takes a bit of getting used to, but
the process is relatively easy to
master with experimentation.Are tilt-shift lenses expensive?
True tilt-shift lens are very expensive,
unfortunately, which is why they are
not commonly used. However, you
can also get less costly novelty
lenses, such as the range from
Lensbaby, that also allows you
to shift the plane of focus inside
the lens for creative effect.Can you mimic the tilt-shift
process in editing software?
All raw editing software will allow
you to fix issues with converging
verticals when photographing
buildings, while Photoshop also lets
you create the ‘toytown’ look from
an image taken with a standard
lens. Some digital cameras also
have a built-in miniature effect.Tech Check
Tilt-shift lenses
Soft and noisy
Q
Why do my images
taken with my
2x extender
seem softer and noisier?
Te rr y Po ulte rA
Using an extender is certainly a
cost-effective way of increasing
your focal length options. Take
a look at the price difference
between a quality 800mm lens and an
extender and you’ll see by how much – it
can be eye-watering. However, this budget
focal length improvement doesn’t come
without a price, and that’s precisely
what you are experiencing.
It’s basically down to how an extender
works. All you are really doing while using
a 2x extender is magnifying the original
image taken at 400mm, rather than
actually shooting at 800mm, as you would
with an expensive prime telephoto of that
length. This means you are also magnifying
any imperfections in your image.
You are also losing light. If your 400mm
has a maximum aperture of f/4, this
becomes f/8 at 800mm. To compensate,you can push the ISO up to get a faster
shutter speed. The resulting image noise is
then magnified in your image, along with a
slight softening. If your 400mm lens isn’t
the best quality in the first place, the drop
in image quality will be more obvious, too.
Using an extender remains a sensible
option, but you need to be aware of itsshortcomings, especially when you’re
shooting in less-than-perfect conditions.
When possible, avoid using high ISOs, and
use a smaller aperture so you get a little
more depth of field. Above all else, it’s still
worth remembering that it is better to have
a noisier image that is acceptably sharp,
than a noise-free one that is blurred!http://www.digitalcameraworld.com MARCH 2021 DIGITAL CAMERA^103
Not a train set: you
can get remarkable
toytown effects with
a tilt-shift lens.An extender can
dramatically increase
the focal length of a
lens, but only with some
loss in image quality.