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03-02-2017, 08:51 PM   #1
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Wrong colour temp in raw file on 645Z when using flash?

Has anyone else experienced that the raw files shot with the 645Z contain the ambient colour temperature when using flash, even when the WB is set to Flash or is set to Auto with the menu option 11 (White Balance when using Flash) set to Flash?

I'm trying to ascertain whether this is actually a bug or not, and I kind of think it is since you'd want your JPEGs properly white-balanced if you were shooting them, and therefore you'd also want your raw files properly flagged to speed your workflow.

As it is I'm just colour-correcting them in Lightroom as I bring in the files, but I'd prefer not to have to.

03-03-2017, 12:19 AM   #2
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I suppose it depends on how much light the flash is contributing to the shot. If ambient light is a significant portion of the exposure then its color temperature is going to show with the WB set to flash.
03-03-2017, 01:03 AM   #3
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My point though is that if you've set the camera to automatically enable flash WB when you use a flash then shouldn't it write that in the raw file as the colour temperature though, since that's what you've specifically chosen?

Or if you've set the white balance to Flash using the WB button?

It seems rather stupid to offer these menu items and then use them only for jpeg files, but maybe that's just me.
03-03-2017, 03:16 AM - 1 Like   #4
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QuoteOriginally posted by paulster Quote

It seems rather stupid to offer these menu items and then use them only for jpeg files, but maybe that's just me.
Many settings only apply to JPEG.

I actually don't want the camera to make any decisions about RAW ... leave it to post, say I!

03-03-2017, 06:39 AM   #5
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Try Custom Setting 11 WB When Using Flash in the C2 menu, set it to "Unchanged". You might also want to set 10 WB Adjustable Range in the C2 menu to "Fixed" if it's on "Auto Adjustment". This one stops it from making minor, but annoying, corrections.


I can't afford a 645z and have never seen one in person, but I was able to afford the pdf manual which shows these settings as familiar ones that annoyed me on my k5iis.
03-03-2017, 06:57 AM   #6
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QuoteOriginally posted by paulster Quote
Has anyone else experienced that the raw files shot with the 645Z contain the ambient colour temperature when using flash, even when the WB is set to Flash or is set to Auto with the menu option 11 (White Balance when using Flash) set to Flash?

I'm trying to ascertain whether this is actually a bug or not, and I kind of think it is since you'd want your JPEGs properly white-balanced if you were shooting them, and therefore you'd also want your raw files properly flagged to speed your workflow.

As it is I'm just colour-correcting them in Lightroom as I bring in the files, but I'd prefer not to have to.
The problem is probably with your flash. What are you using? Most small flash guns have a color shift to them when you change the power level. Shoot a grey card or color checker to set your white balance for that power setting.
03-03-2017, 07:05 AM   #7
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The menu option 11 point 3 (flash) means that the WB is not measured until the flash is triggered. It does not mean that the White Balance is set to flash (5400 K). Depending on the light set, ambient light is always present. How much can you easily measure with an external exposure meter. Correctly point 4 would be unchanged and then make the WB over the normal WB selection.

JPEGs do not contain WB / Kelvin values. Lightroom provided for RAW's basically wrong values, with every camera I know.

You can easily check this:
Take an exposure series with the 645Z. Specify the Kelvin value manually. For example starting with 5000k in 300k steps to 5900k.

The result looks like this:
645Z................LR
5000K..............5350K
5300K..............5650K
5600K..............6000K
5900K..............6350K

The value in LR drifts, but not at the same distance. There is no fixed conversion value. This makes LR different for each camera. My D810 drifts differently than my A7RII and the 645Z.

I've noticed because one had photographed with two cameras and I wanted to balance the WB. The results were very different. Logically when 5600K on the D810 is not also 5600K at the A7RII or the 645Z - in Lightroom - are.

Perhaps helps you to further narrow the error.

Greeting Gerd
03-03-2017, 01:13 PM   #8
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Gerd

Thanks for your reply.

I did some testing and realized that the camera is indeed writing out a consistent value for flash colour temperature when either Flash WB is chosen or menu option 11 is set to automatically use Flash WB when using flash.

But the colour temperature that is either passed to Lightroom, or that Lightroom interprets, is wrong.

A couple of tests I did, similar to yours:
645Z........LR
5K............5100+8
Cloudy.....6100+18
Daylight...5050+23
Flash.......6400+16
AWB.........6400+16 (flash enabled) / 5050+23 (flash disabled)

Lightroom measured flash from grey card: 5600+32

So the flash value that Lightroom is reading from the raw is nowhere near the measured value, and the measured value looks far more like I'd expect it to.

I wonder now if this is a Lightroom bug in how it interprets the DNG file, or a 645Z bug in how it is writing the colour temperature to the DNG file.

03-03-2017, 11:42 PM   #9
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Are you using a camera profile other than "Adobe Standard" or "Embedded"? I use Huelight profiles for the 645Z and these profiles change the colour temperature (amongst other things).

Bob
03-04-2017, 06:27 AM   #10
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@paulster

This is a problem of Lightroom - since version 4.x up to today.

That have all the cameras - not only the 645Z. The problem is that each camera has different differences. Even from the Nikon D750 to the D810 the difference values are very differently large. This makes it difficult to synchronize the WB when photographed at one event with two different cameras.

@BOB L

I have tested with the adobe standard profile. The embedded differ slightly from Adobe standard profile - from me.

Greeting Gerd
03-04-2017, 07:43 AM   #11
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QuoteOriginally posted by Gerd Quote

@BOB L

I have tested with the adobe standard profile. The embedded differ slightly from Adobe standard profile - from me.

Greeting Gerd
profiles were moving the WB around

Interesting Gerd. I went through a bunch of shots and Adobe Standard and Embedded showed the same value each time whilst the various Huelight profiles were moving the WB around (Lightroom 6)

Bob
03-04-2017, 06:07 PM   #12
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So I use Anders Torger's DCamProf profiles and I found the following when I tried switching profile on the same image:
Embedded 6100+23
Adobe Std 6400+16
Camera Natural 6400+16
DCamProf 6400+16

It seems that all are interpreting the file as 6400+16 with the exception of Embedded. And none of them are close to the correct value metered from the grey card.
03-05-2017, 03:16 AM   #13
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QuoteOriginally posted by Bob L Quote
profiles were moving the WB around
Hello Bob,

that's right. Also the Huelight profiles and other profiles, which I also use, move in most cases the WB.

Greeting Gerd

---------- Post added 03-05-17 at 03:17 AM ----------

QuoteOriginally posted by paulster Quote
So I use Anders Torger's DCamProf profiles and I found the following when I tried switching profile on the same image:
Embedded 6100+23
Adobe Std 6400+16
Camera Natural 6400+16
DCamProf 6400+16

It seems that all are interpreting the file as 6400+16 with the exception of Embedded. And none of them are close to the correct value metered from the grey card.
Hello Paulster,

the standard Adobe profile or the embedded profile, but if the camera is set to neutral, the WB in Lightroom may not be allowed to move this.
The manufacturer production tools such as Capture NX for Nikon or also Digital Camera Utility for Pentax do not do that either. In these tools exactly the WB is displayed which I have adjusted in the camera - on the Kelvin exactly.

What is conspicuous is: If I set fixed WB profiles in the camera such as Daylight, Cloudy etc .. then the deviations in LR is not so strong. If I adjust manual values in kelvin - and I do almost always - then the deviations in LR are in part considerable.

Of course this is not a broken leg, because you can always influence the WB - in the RAW file - in 100%. But if Adobe writes to the controller a value - like Kelvin - and that's not true. Then they should write to the controller only "for fun".

Alternatively, a manual entry would be appropriate why and how the WB value in Adobe products is composed. Then all can handle it.

Greeting Gerd

---------- Post added 03-05-17 at 03:34 AM ----------

Supplement - I had just forgotten on the subject WB in LR:

For example, if the kelvin value is "as shoot" equal to 5400K - then LR does not sync 5400K between different photos but only the value "as shoot". You have to change the value to 5401K and then the kelvin value and not the value "as shoot" will be synchronized.

In LR, unfortunately, there are many inconsistencies on WB.

Greeting Gerd
03-05-2017, 04:24 AM   #14
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QuoteOriginally posted by Gerd Quote

[/COLOR]Supplement - I had just forgotten on the subject WB in LR:

For example, if the kelvin value is "as shoot" equal to 5400K - then LR does not sync 5400K between different photos but only the value "as shoot". You have to change the value to 5401K and then the kelvin value and not the value "as shoot" will be synchronized.

Greeting Gerd
That's a useful bit of information, Gerd.....thanks.

Bob
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