The OnePlus 8 Pro is one of the year's best smartphones so far, thanks to a fantastic combination of powerful internals, great battery life, light software and one of the best displays on the market. But one part of its camera system seemed virtually pointless when we reviewed it at launch: the colour filter or photo chromatic camera. 

It's a low resolution sensor that seemed only to do quite odd things to colour, making blue skies orange, and stripping out a lot of colour. During announcement, it didn't seem all the clear why anyone would find it useful. 

When we asked the company about it initially, we were told it "processes light differently, to generate a surreal image with a unique colour tone". But it turns out that way of processing light is actually very different. 

In fact, with the right kind of material in front of it, it can see through surfaces your human eyes can't see through. Specifically, it can see through materials that are infrared transparent.  

Images started appearing on social media of various people sharing photos they'd taken with the OnePlus 8 Pro's colour filter camera which showed they could see internal components of various objects. While it's not X-Ray technology, it has that X-Ray look to it. 

One perfect example is the Apple TV Box. Pointing the camera at it revealed something we didn't previously realise: the entire outer case is transparent to infra-red, and so using the Photochrom filter setting on the 8 Pro sees through it, into the internal housing inside the box. 

This confirms, then, that OnePlus' unusual colour filter camera actually has an IR sensor. And so, if you point it at the end of your smart TV remote, you'll see some componentry behind there too. 

If you have a OnePlus 8 Pro, try it out. See what plastic or glass items have unexpected IR transparency. You might be surprised. You'll be able to see through a glass-hobbed cooker to the wiring and elements underneath, or even see some crazy flashing and flaring up from any infrared scanners like FaceID on an iPhone, or the sensors on AirPods Pro. 

The only downside - as we found in our review - is that it really doesn't like focusing on objects close up, and so while you can see through stuff with the camera, it's not the simplest task in the world to take an in-focus detailed shot.

For more tips and tricks, check out our video below, or head to our more extensive written guide.