Lens flare causes purple haze in iPhone 5 camera images: Review

Users across the globe are taking to forums and websites to complain about issues with the iPhone 5’s camera. As per a recent review of the camera published by Digital Photography, we now know a little more about what causes the purple haze seen in some images captured with the iPhone 5.

According to the quick review posted by the site commonly referred to as DP Review, the authors Barney Britton and Kelcey Smith, have put to rest certain speculations such as sensor blooming, chromatic aberrations and sensor quality that were once touted as reasons behind this purple anomaly seen in the captured images.

An 8MP camera called iSight

Explaining each issue, the authors note that it is not sensor blooming as, “Blooming happens when the intensity of the light reaching the sensor is so great that there is an overflow of electrons that spill over into adjcent pixels. This is not a satisfactory explanation for the iPhone 5’s purple haze, since sensor blooming affects the entire imaging field, meaning that you’d see it associated with a bright highlight positioned anywhere in the image, not just towards the edges of the frame, as we’re seeing in pictures from the iPhone 5.”

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They go on to dismiss the fact that it is caused by chromatic aberrations, “Typically visible towards the edges of the frame especially in images taken using wideangle lenses, CA takes the appearance of a green-and-magenta or blue-and-yellow ‘fringing’ around peripheral scene elements. It looks nothing like the iPhone 5’s purple haze.” Lastly they dismiss the fact that the iPhone 5’s sensor is really sensitive to infrared light.

The reason for this purple haze, they say, is either internal reflections or lens flare. Explaining this point, the authors of DP Review state, “The most likely cause of the iPhone 5’s purple haze is probably lens flare and internal reflections in the camera lens assembly. All lenses are succeptable to lens flare to some degree, and as you can see from the images at the top of this page, the iPhone 4S isn’t immune either (ditto the iPhone 4 and competitive smartphones from other manufacturers). But in our shooting we’ve found that it’s a little more noticeable on the iPhone 5. So why is that? It’s unlikely that the flare is solely due to the much-vaunted inclusion of a sapphire glass lens cover (although the refractive index of the sapphire glass is different to conventional optical glass, so it could be a contributing factor). Our money is on it being caused by a combination of different things, none of which, alone, is unique to the iPhone 5.”

This points to the fact that it is due to the hardware of the device and not the software as with the Maps fiasco, where Apple will in the run up dodge the bullet. DP Review concludes the report by stating, “Really, our advice is not to worry. Just do what you should do anyway, and avoid putting bright lights near the edge of the frame when shooting.”

This should put most people’s minds to rest and this should come as a sort of comfort for those looking to purchase the iPhone 5.