April 27, 2015

Your iPhone Is Now a Professional Light & Color Meter

Cine Meter II with Luxi Color Metering
Light metering apps and accessories have been around for years, but color metering has remained elusive in the realm of smart phones. Until now.

Traditionally, dedicated color meters are incredibly expensive, with higher-end models from Sekonic coming in at upwards of $1700. Our friend Adam Wilt, designer of the popular Cine Meter II iPhone app, recently rolled out a massive update to his already-stellar app, and it includes powerful new color metering features that are surprisingly accurate.

Here's what Adam has to say about how the new 1.6 update works, and how accurate it is compared to traditional color meters.

Cine Meter II continuously reports the correlated color temperature and green/magenta tint of the light, and tapping the temperature and tint readouts calls up a color correction panel suggesting the gels needed to match the lighting to your camera's target white balance.

Cine Meter II closely matches other color meters on full-spectrum lights such as tungsten or sunlight. For lights with "spiky spectra" such as fluorescents, LEDs, and HMIs, no two color meters seem to agree with each other, but Cine Meter II is usually no worse at reporting temperature and tint than "real" meters under the same conditions.

I've posted test results showing how Cine Meter II's readings compare with those of color meters from Minolta, Sekonic, and Asensetek. Two months of beta-testing by cinematographers worldwide confirmed that Cine Meter II's color measurement was good enough for production use, so now it's available to all.

Color metering, even more so than light metering, is becoming a vestige of the days of celluloid production, an art that is disappearing as digital cameras and on-set monitoring become ubiquitous. However, much like metering light, color metering can provide really helpful and actionable information about how to handle and manipulate the color in your scene. Where color meters become extremely helpful is when you're dealing with mixed sources of light, many of which have different color temperatures that may or may not work well together in the final image. And now, the barrier for professional color metering is lower than it has ever been with this update to Cine Meter II.

Though Cine Meter II works as a standalone metering app, the color metering and incident metering require a Luxi photosphere attachment. Cine Meter II is currently available through the App Store for $25. If you purchased an earlier version of Cine Meter II, the upgrade is free.     

Your Comment

18 Comments

I've used Lumu and it's great. The addition of color temp is well worth the money.

April 27, 2015 at 6:32PM, Edited April 27, 6:33PM

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I should mention that Lumu doesn't support color measurement; it uses a monochrome sensor. You'll need a Luxi for incident color metering. You can also turn on color metering for reflected readings (no attachments required) but you'll want a color-neutral white card to aim at for accurate readings.

April 28, 2015 at 4:51PM

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Adam Wilt
239

Hi,
Here's Adam presenting his new Cine Meter II at our Digital Cinema Society "Cinema Lighting Expo" that we held back in March:
https://vimeo.com/123949028

The rest of our Cinema Lighting Expo videos can be found here:
http://www.digitalcinemasociety.org/new-streaming-videos

April 27, 2015 at 6:56PM, Edited April 27, 7:15PM

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Thanks for your posting! The video is really helpful.

April 27, 2015 at 7:33PM

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Thanks for the post. The NAB coverage is awesome too. Definitely gonna bookmark your website.

April 27, 2015 at 7:37PM

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Kevin Greene
Editor
707

Thanks. And please feel free to share!

April 27, 2015 at 8:52PM

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the luminance of the phone screen itself shouldn't influence tha white semisphere?

April 28, 2015 at 6:30AM

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An excellent question! I just tested it in a fairly dark room illuminated by a combination of my computer screen and some ambient spill from the hallway, but no other lights (around 5 lux, or f/1.4 and 3/10 stops at 1/24 sec, ISO 3200), with my iPhone 5's screen at maximum and minimum brightness:

At maximum: 5.2 lux, f/1.4 and 4/10 stops. CCT 4350K, 5 Magenta
At minimum: 5.0 lux, f/1.4 and 3/10 stops. CCT 4150K, 11 Magenta.
Masking the screen with black paper: same as minimum readings.

So the reported exposure difference in this situation is about 1/10 stop, 200 K in color temperature, and 6 points of tint (1/5 full green). It's present, but not significant; I saw more variation in readings based on how I leaned forward to read the iPhone as it was sitting flat on the table and whether or not I was reaching for the screen to change the brightness.

Even so, in low light you should probably reduce screen brightness for best results. I normally have my brightness pretty low anyway (I'm paranoid about battery life) and have auto-brightness on, so I hadn't noticed "light pollution" from the screen before. I'll add this to the app's instructions and FAQ page.

If you're still concerned about this, perform incident readings with the front camera (facing away from the screen). That way there's no direct light pollution from the screen, only what reflects from the environment.

April 28, 2015 at 2:42PM

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Adam Wilt
239

"If you're still concerned about this, perform incident readings with the front camera (facing away from the screen). That way there's no direct light pollution from the screen, only what reflects from the environment."

Sorry, I assume you meant back camera, not front?

May 13, 2015 at 11:27AM

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PJ Palomaki
Cinematographer | Motion Graphics
400

Sorry about that: yes, the back camera, the one facing away from you.

May 16, 2015 at 7:27PM

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Adam Wilt
239

I've been wanting to buy one of these for a year or so now. The only thing that ever stopped me was the fact it wasn't a color meter too. Buying one today, pretty excited about this

April 28, 2015 at 1:58PM

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Charles C.
Editor/ Director/ Director of Photography/ Wannabe Thinker
1117

Ah. An instant buy. I already had Cine Meter. Really looking forward to keeping a full-fledged spot/incident meter in my pocket. Now, I can tuck my Sekonic meter in my cine bags.

Michael

April 28, 2015 at 9:34PM, Edited April 28, 9:34PM

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Michael Morlan
Director / Director of Photography
161

Where can I get the sphere attachment?

April 28, 2015 at 11:47PM, Edited April 28, 11:47PM

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This is really really great! I have been developing my own LED lights and being able to test the color temp is very important!

April 30, 2015 at 10:40AM

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Michael Ford
Owner / Wedding Photographer / Do everything
74

Where can you buy the attachment?

May 4, 2015 at 3:00PM

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Ryan Atkins
Cinematographer/Editor/Colorist
167

Great question, Ryan! Luxi is available at http://esdevices.com, and we ship worldwide.

Jarrod Whaley
Operations, ESD

May 4, 2015 at 4:23PM

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Jarrod Whaley
Operations Manager at Extrasensory Devices
81

Thanks Adam & Jarrod, bought both Luxi and CineMeter II, thanks to this post and as your products seem like they're worth the money!

May 13, 2015 at 11:31AM

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PJ Palomaki
Cinematographer | Motion Graphics
400

so what's the white thing? if that's required, it's not mentioned anywhere.

April 15, 2016 at 11:30PM

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Stanley
81