Dual camera systems have been around for the longest time, and only recently phone makers started putting even more camera modules into their mainstream devices. It started with Huawei when it released the Huawei P20 Pro with its Leica Triple Camera system, and now, some manufacturers have followed suit; most notably Samsung with the new Galaxy A7.

In fact, the Korean company pushed things even further by introducing the Samsung Galaxy A9 with four cameras on the back – in what world will you need that many camera sensors? Well, that’s what we’re here to discuss, and why more is not necessarily better.

First, let’s analyse the P20 Pro’s triple camera system. The primary sensor is a 40MP f/1.8 RGB shooter, and it’s complemented by a 20MP f/1.6 monochrome camera. The monochrome sensor isn’t just there for show: not only does it assist the primary sensor to capture more impressive shots, it’s also used to simulate bokeh effects.

As for the third sensor, it’s an 8MP f/2.4 telephoto shooter, and I’d argue this is the least necessary component in the P20 Pro’s camera system. Yes, the telephoto shooter does grant the ability to do 3x optical zoom – allowing you to get closer to a subject or get tighter framings – but the image output from that sensor pales in comparison to the main 40MP shooter.

Even without the 8MP telephoto sensor, I reckon the P20 Pro’s excellent image quality will still be retained. I’ve used the P20 Pro as my daily driver for a while in the past, and I honestly don’t recall ever using the phone’s optical zoom in any meaningful way. Of course, that’s just my usage habit: I’m sure there are folks who will appreciate the flexibility of the telephoto sensor.

Now, let’s move on to the Galaxy A9, or what Samsung dubs “the world’s first quad camera smartphone.” The A9’s rear cameras are made up of a 24MP f/1.7 shooter, an 8MP f/2.4 ultra-wide camera, a 10MP f/2.4 telephoto sensor, and finally, a 5MP f/2.2 “depth camera,” which is used for bokeh simulation.

Essentially, what you’re getting with the Galaxy A9 is shooting flexibility; sort of how it is with the LG V40 ThinQ. You can use the A9’s main 24MP camera for normal photography, the 8MP ultra-wide sensor for wider shots, and the 10MP telephoto shooter for close-up shots.

But the main issue here lies in camera performance: with so many different camera sensors, the Galaxy A9’s image quality will vary widely. The phone’s shooting flexibility has its appeals, but if there’s a large discrepancy in image quality between these different cameras, it will affect the overall user experience.

I haven’t had the Galaxy A9 in my hands yet to see how its cameras perform, but I did manage to spend some time with the Galaxy A7, which has a similar camera setup as the former; it’s only missing the telephoto lens. If the A7’s camera performance is any indication of how the A9’s cameras will perform, it’s not great.

The Galaxy A7’s primary 24MP sensor takes decent-looking shots, but the 8MP ultra-wide camera isn’t quite as capable: images come out looking darker than shots taken with the main sensor, and the colour temperature is on the warmer side of things too. On top of that, the A7’s Live Focus mode – which uses the 5MP sensor to simulate bokeh effects – has difficulty properly separating the subject from the background.

So why are phone makers equipping so many camera sensors on their devices if it doesn’t bring any meaningful user experience? It boils down to marketing. After all, it sounds good to boast that your phone has three, or even four camera sensors compared to only one. It’s the numbers game: bigger numbers simply sound better, even though they don’t necessary translate to better user experience. That’s the same case with the amount of RAM on your smartphones.

Take the recently unveiled Pixel 3 and Pixel 3 XL. Even though both of Google’s latest phones only have a single rear camera, their camera performances are considered to be some of the best – if not the best – in the market now. The Pixel 3 phones may not have the shooting flexibility of the Galaxy A9 or P20 Pro, but their superior image qualities more than make up for this – in my opinion, of course.

If you’re looking to buy any particular new smartphone, don’t be too caught up on the number of cameras it has – just because a phone has multiple cameras doesn’t necessarily mean it can take amazing images. If Google can deliver excellent camera performance with a single camera sensor on the Pixel 3 and Pixel 3 XL, so can other manufacturers.