HOW WE TEST

Computeractive is owned by Dennis Publishing, which owns a hi-tech facility for testing the latest technology. You’ll often read references to our benchmark testing, which is a method of assessing products using the same criteria. For example, we test the speed of every PC and the battery life of every tablet in exactly the same way. This makes our reviews authoritative, rigorous and accurate.

Dennis Publishing also owns the magazines PC Pro, Computer Shopper and Web User and the websites Expert Reviews ( www. expertreviews.co.uk) and Alphr ( www. alphr.com). This means we can test thousands of products before choosing the most relevant for Computeractive.

What does it do?

Er, takes pictures, obviously.

Why would I want it?

Fair question, because 93 per cent of adults in the UK now use a phone, and almost all have a built-in camera. Photographers have a saying: “The best camera is the one that’s with you.”

What’s the catch?

Mobile phones are great at autofocus and colour balance, but their tiny cameras have optical limitations. Most are wide angle, equivalent to about a 28mm lens on a full-frame camera. That lets you fit a lot into a picture, and shoot in confined spaces. But street photography is traditionally done with a 50mm lens, while portrait photographers use 85mm or longer. That’s why faces in photos taken on phones either fill only a small part of the frame or show ‘big nose’ effect when close up. A zoom lens lets you adjust the focal length, but this requires a certain amount of physical space; whereas phones can only fake a zoom by taking a wide-angle snap and cropping it.

Finally, using a full-size camera with a ‘fast’ lens (which gathers a lot of light) you can create a ‘bokeh’ effect, blurring of the background and foreground that makes your subject pop out. Dual-lens phones, like the Huawei Mate 9 (pictured), can now simulate this by combining images shot at two focal lengths, but the results are mixed.