Digital Camera World - UK (2019-08)

Help me buy a... Telephoto lens

What to look for

in a telephoto

Here’s a closer look at the Sigma

150-600mm f/5-6.3 Sports

Image stabilisation

This Sigma lens has optical stabilisation

built in, with one mode for regular use

and one specifically for panning shots.

Other controls include a zoom lock

switch, full time manual focus

override and a focus limiter switch.

http://www.digitalcameraworld.com AUGUST 2019 DIGITAL CAMERA^131

Tripod mount

This lens comes with

a tripod mount on a

rotating collar (for

vertical or horizontal

shooting or use with a

gimbal), and has three

tripod sockets to allow

for different camera

combinations and

balancing points.

Maximum aperture

This varies from f/5 at 150mm to f/6.3

at 600mm. It’s not ideal to have a lower

maximum aperture as you zoom in, but

a constant-aperture zoom with this

range would be prohibitively expensive,

or perhaps not even possible.

Optional teleconverters

Sigma also makes 1.4x and 2x

teleconverters, which fit between

the lens and the camera body to

extend its focal range still further,

but they reduce the effective

maximum aperture by one and

two stops respectively.

Zoom range

The 150-600mm focal

range is ideal for aviation,

bird photography and

other long-range

subjects; on an APS-C

format camera, this lens

effectively offers an even

longer 225-900mm range.

Weather resistance

The Sigma is designed to resist both dust

and moisture. It has a water- and oil-repellent

coating on both the front and rear elements

to reduce smears and water droplets.

Balancing act

Bigger telephotos have

a bracket to attach the

lens to a tripod. The lens

weighs more than the

camera, so this is a much

better way to balance the

weight than the camera’s

own tripod socket.