Using a Canon DSLR loaded with ML as a nifty color meter ;)

[noisyboy]

Hey all!

So I'm on set at the moment and we are shooting for the first time with a BMCC but the DP has accidentally left his color meter on another location and there is no way to shoot a white card and auto WB the camera.

Sooooo... basically I'm wondering if I get the stills photographer to allow me to set up ML on his mkII (who wouldn't anyway right?), is there a way I can use this to give me a temperature reading? I know there is the one button WB feature (which I love) so if I used that would it then give me the reading in kelvin? I know that if I did this with the Canon menu function then you can't see the reading due to it being hidden when you select custom WB. Only other way is to shoot a white card and fix in post but as we're shooting ProRes and not Raw I'd rather get it right in camera.

Would be ace if this were a feature to simplify the process and my camera could be used as a color meter

Any help would be appreciated as we Turnover in an hour!

Cheers dudes! 

Kraig.

[John Kesl]

Hi Sir,
If you've got an iPhone there is an app. ProCamera is good and Cine Meter is my personal favorite. Sorry, if I can't be of more service.
JK

[John Kesl]

I know it's a tad rudimentary.

Also,
for quick reference. Daylight is 5500, open shade 7000, kino flo 4000 or there a bouts, tungsten 2800-3200, HMI/LED 5200-5700. florescent lights plus magenta, (if it looks orange, raise the kelvin, blue, lower the kelvin).
From sunrise till about 10 kelvin will go up from 3800ish to 5500, in the afternoon in the northern hemisphere in the summer around the 40th parallel, past 5pm until sunset the kelvin will drop from 5500 to 3800 again. also High noon tends to be a tad bluer.
I mean in no way to condescend to you, if you already know this stuff. just thought I'd share some quick and dirty ways to set WB.

[SDX]

I'm not really sure if it is still there, but under 2.3, in the exposure menu, you'll find the abillity to measure the WB. It takes a few seconds in which you'll have to hold the camera still, but it works well.

[noisyboy]

I know it's a tad rudimentary.

Also,
for quick reference. Daylight is 5500, open shade 7000, kino flo 4000 or there a bouts, tungsten 2800-3200, HMI/LED 5200-5700. florescent lights plus magenta, (if it looks orange, raise the kelvin, blue, lower the kelvin).
From sunrise till about 10 kelvin will go up from 3800ish to 5500, in the afternoon in the northern hemisphere in the summer around the 40th parallel, past 5pm until sunset the kelvin will drop from 5500 to 3800 again. also High noon tends to be a tad bluer.
I mean in no way to condescend to you, if you already know this stuff. just thought I'd share some quick and dirty ways to set WB.

Hey dude Thanks for the reply! The main issue we have is balancing the house practicals with CT so they match the other sources. For example if we have daylight coming in (which we don't right now but just as an example)  and we are say in an office space with flouries in the ceiling then it would be nice to be able to white/grey card under them to see what CT they need to get them to match 5600k

Might check out that app but doesn't the iPhone change it's White Balancing dynamically?

Thanks again for your help! Might just put ML on the camera anyway as I'm sure I remember the ML white balance feature giving a kelvin readout. 

[noisyboy]

I'm not really sure if it is still there, but under 2.3, in the exposure menu, you'll find the abillity to measure the WB. It takes a few seconds in which you'll have to hold the camera still, but it works well.

Thanks man! Gonna have a go

[noisyboy]

I mean in no way to condescend to you, if you already know this stuff. just thought I'd share some quick and dirty ways to set WB.

Ps. No problem at all dude, not in the least bit condescending Any help offered should always be positively received IMO

[1%]

6D will do this, its auto ml WB with the shortcuts. It gives a setting for kelvin but I have no clue it will match other cameras.

So you press set and it rests on a K value + does shift/etc.

[John Kesl]

Hey dude Thanks for the reply! The main issue we have is balancing the house practicals with CT so they match the other sources. For example if we have daylight coming in (which we don't right now but just as an example)  and we are say in an office space with flouries in the ceiling then it would be nice to be able to white/grey card under them to see what CT they need to get them to match 5600k

Might check out that app but doesn't the iPhone change it's White Balancing dynamically?

Thanks again for your help! Might just put ML on the camera anyway as I'm sure I remember the ML white balance feature giving a kelvin readout. 

re: the iphone apps mainly cine meter, it reads the white ballance adjustment (I think) 

[Audionut]

Expo menu | White balance | Auto adjust Kelvin + G/M

Make sure the spot meter is on the grey card then take a reading.  That same menu item will then show the temperature and G/M shift.

[noisyboy]

Amazing! Strong work all! Using the auto WB actually works pretty damn well for this purpose for anyone who has the same issue

Now Blackmagic just need to pull their finger out and have some proper meters and stuff in their cameras instead of you having to lug a damn mac around with you! Still a boss camera though but still another reason why it wont replace my DSLR just yet 

[noisyboy]

Just thought I'd do a little update on this for anyone who is interested. Gonna have a try at buying one of those ExpoDisc thingamajigs (that is basically a lens cap that you can use to white balance with for those not in the know) and using that with Magic Lantern to basically turn my 6D into a cool little color meter in conjunction with the ML auto WB function. If anyone has any recommendations on a cheaper version of the ExpoDisc I'd be into hearing your recommendations. Pretty excited to try this out on a commercial this week I'll post my results!

Peace 

[arrinkiiii]

Hi noisyboy, did you manage to use ML for color metering?

[noisyboy]

Hi noisyboy, did you manage to use ML for color metering?

So sorry I've didn't see this dude! Yeah - it actually worked out pretty well

I basically used a cheap expodisk and managed to use the kelvin readings to match sources etc!

Bonus!

[ItsMeLenny]

I wonder if it could be used for monitor calibration.

[Audionut]

It would only be useful for the greys.

Monitor calibration involves a whole lot more.  Color, gamma, gamut mapping, ICC profile creation, etc.

[ItsMeLenny]

It would only be useful for the greys.

Monitor calibration involves a whole lot more.  Color, gamma, gamut mapping, ICC profile creation, etc.

This what you say is true. Although it might be helpful for the colours, depending how accurate the camera is.

But the 'colorhug' is essentially just a camera. http://www.hughski.com/

[Audionut]

Lenses effect luminance/color.
At the end of the day, you wouldn't get accurate results, and some results may end up worse then before you started.

Research monitor calibration.  Be prepared to get lost in a world of gamut mapping, gamma transfer functions, LUT's, and a whole host of other complicated crap.  And this is trying to use a dedicated colorimeter.  Argh!  The more you research, the more you find, you were probably doing it wrong beforehand. 

[noisyboy]

Yup - totally agree with this. I had the same idea before but realised it's not worth the hassle of trying to implement it with a camera. I've been actively trying to get my head around monitor calibration for the last year and I'm still confused. Even when you manage to get your monitor calibrated you then enter the confusing world of colour management within your applications. For example Photoshop and Lightroom are colour management "aware" whereas Davinci Resolve or Speedgrade aren't (which is mental) which means you then enter the glorious world of LUT conversions etc. TOTALLY worth learning but expect it to be confusing as hell. MixingLight.com just started a great series on demystifying calibration but it's a subscription paid site (that doesn't cost the earth though but still...) so I'd suggest you start there if you can.