Cine Meter II for iPhone

[AaronChicago]

Not sure if you guys have seen this, but the newest update allows for color temperature readings: http://www.adamwilt.com/cinemeterii/

All you have to do is buy this Luxi adapter, attach it on your iPhone camera, and the app reads out nearly perfect color temp.

 

[tupp]

All you have to do is buy this Luxi adapter, attach it on your iPhone...

​What Iphone?

 

By the way, it also works on Android devices.

[adamwilt]

Thanks for the shout-out, AaronChicago.

To be clear, Luxi works on Android devices as well as iOS: it's a simple clip-on photosphere that converts the built-in camera into an incident-light sensor. The Luxi folks have free apps on both iOS and Android for incident light metering. It's pretty cool:

http://www.provideocoalition.com/review-luxi-for-all-incident-metering-photosphere-for-ios-and-android

Cine Meter II, however, is iOS-only. And I don't claim to read out nearly perfect color temp <blush>, only that Cine Meter II's color readings are about as good as other color meters ( http://www.adamwilt.com/cinemeterii/colormetering.html ). Color metering turns out to be fraught with difficulty and uncertainty, and even "real" color meters often interpret the same source rather differently: http://www.dvinfo.net/article/production/lighting/on-the-color-of-light-and-the-measurement-thereof.html .

[AaronChicago]

Thanks for the shout-out, AaronChicago.

To be clear, Luxi works on Android devices as well as iOS: it's a simple clip-on photosphere that converts the built-in camera into an incident-light sensor. The Luxi folks have free apps on both iOS and Android for incident light metering. It's pretty cool:

http://www.provideocoalition.com/review-luxi-for-all-incident-metering-photosphere-for-ios-and-android

Cine Meter II, however, is iOS-only. And I don't claim to read out nearly perfect color temp <blush>, only that Cine Meter II's color readings are about as good as other color meters ( http://www.adamwilt.com/cinemeterii/colormetering.html ). Color metering turns out to be fraught with difficulty and uncertainty, and even "real" color meters often interpret the same source rather differently: http://www.dvinfo.net/article/production/lighting/on-the-color-of-light-and-the-measurement-thereof.html .

​Hey! Thanks for clearing that up. I guess I should have said near perfect compared to the $1500 meters.

[Nick Hughes]

LED lighting can often give inaccurate color readings, even to expensive meters since they don't have the same kind of smooth spectrum that other sources do. Just something to keep in mind.

[AaronChicago]

LED lighting can often give inaccurate color readings, even to expensive meters since they don't have the same kind of smooth spectrum that other sources do. Just something to keep in mind.

​True. I don't have much experience with LEDs but I can imagine that is an issue right now.

[AaronChicago]

FYI. I've been doing some testing with the Luxi vs iPhone 6 front camera. The iPhone camera is consistently off -300k in every source I've tested. If you did not want to spend $29 on the Luxi adapter you could just use your phone camera and adjust for that -300k every time.

[adamwilt]

FYI. I've been doing some testing with the Luxi vs iPhone 6 front camera. The iPhone camera is consistently off -300k in every source I've tested. If you did not want to spend $29 on the Luxi adapter you could just use your phone camera and adjust for that -300k every time.

​Color readings are exceedingly sensitive to calibration and to whatever you're using (if anything) over the lens: I have two Luxi For Alls from different production runs, and one reads 200K warmer than the other, though they're identical to the eye.

If you want to run in reflected mode (there's a switch for that in Settings), calibrate reflected-mode camera "sensors" separately from the Luxi "sensors"... and make sure you're using a color neutral measurement target for reflected readings, like a DSC Labs OneShot (white/gray side) or a white-balance card (various vendors) or the like (most white paper isn't really neutral; some types even have brighteners added that fluoresce under UV light).

Tip: if you want incident color temperature but don't want to use Luxi, cut a small bit of Lee 216 diffusion and hold it (or tape it) over the camera (and calibrate through it, of course!). It's not nearly as convenient, but it is cheaper... and it works pretty well.

[Jarrod Whaley]

I am the Operations Manager at Extrasensory Devices, the manufacturer of the Luxi light meter attachment for smartphones.

I just wanted to chime in to say that you should always be sure to calibrate any light metering app you might be using with Luxi. As Adam points out, there can be slight differences between Luxi attachments--but there can also be small differences in sensitivity between any two smartphones, as well. Manufacturing is never a perfect science, and tiny aberrations from design specs are often seen. These tiny differences can actually make a big difference in the actual amount of light being measured, so calibration is key.

By the way, here is a link to our User's Guide, which ought to give you a good idea of how our product works.

Finally, if you have any questions about Luxi For All, feel free to ask away!