Why do pictures of fire come out purple?

Question

When I'm taking pictures of my log fire the flames and embers come out in rich shades of purple rather than red. I've tweaked everything I can on my camera; white balance, metering, ISO, exposure, but nothing makes a difference.

I'm assuming there's some obvious reason for why this is happening but I'm at a loss. Why are my pictures coming out purple?

Using a Sony Xperia Z camera phone

EXAMPLE
Example of purple embers

I realize this has been solved, but any chance you could post a sample image. I'm really curious what it looks like and it would make it easier for those unfamiliar with the problem to see what's happening. — AJ Henderson, Dec 30 '13 at 14:44
No worries @AJHenderson, I deleted most of them but I kept the one I've attached as I thought it looked kinda cool :D — CLockeWork, Dec 30 '13 at 14:50
Oh wow, that's crazy. I've honestly never seen a camera do that before, but then again, I'd be a little upset if my high end DSLR didn't have a good IR filter and I don't think I've ever thought to point my smartphone at a fire before. Now I'm curious to try though. — AJ Henderson, Dec 30 '13 at 14:55
Is there any way of finding out? I doubt it has one, but I've been surprised several times by the range of features it has (mind you that's technically the features the built in camera software has) — CLockeWork, Dec 30 '13 at 16:56

Digital Lightcraft · Accepted Answer · 2013-12-30T21:16:29.750

19

What you are seeing is Infra-Red (AKA 'IR')

The sensor (probably) has an IR filter, but strong sources such as fire can still get through, and show up as a light purple on most CCD / CMOS sensors.

edited Dec 30 '13 at 21:16

answered Dec 30 '13 at 10:42

Digital Lightcraft

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Thanks Darkcat. Is there any way to counter it (short of PhotoShop)? – CLockeWork Dec 30 '13 at 11:27
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not really - the only method i can think of is to find some sort of extra IR filter and put it over you lens. You could possibly get one off a dead camera sensor. – Digital Lightcraft Dec 30 '13 at 11:39
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that wouldnt fit. on thorlabs and edmundoptics you can find IR cut filters in all sizes mounted and unmounted. – Michael Nielsen Dec 30 '13 at 11:44
@MichaelNielsen - yes it would, use blu-tak. – Digital Lightcraft Dec 30 '13 at 11:48
are you talking about putting in on the sensor or the lens? – Michael Nielsen Dec 30 '13 at 11:50
ah, just noted that we are talking about a camera phone, lol :) – Michael Nielsen Dec 30 '13 at 11:55
Well, you can get stick on lense for camera phones so I'm hoping I can get a filter that way – CLockeWork Dec 30 '13 at 12:16
@CLockeWork - its highly unlikely you'll find a ready-made IR filter for your phone tbh... – Digital Lightcraft Dec 30 '13 at 12:40
@DarkcatStudios, yeah it's sure looking that way; fish-eye lenses, wide angle lenses, even tripods... but no IR filters. Oh well, I'll have to get a real camera soon enough anyway, though this one is surprisingly comprehensive :D – CLockeWork Dec 30 '13 at 12:44

Why do pictures of fire come out purple?

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