Hi all,

I didn't have a problem with the E-1 that I was aware of, but the D300 files were showing some strange WB values when imported into Capture One 4.  Shots that I took under a cloudy sky have temps of 4400K.  And my previous preset of 6500K now jumps the slider upto 7300K 

I've been reading Phase One's official line on this and the foum gets quite angry with anyone asking again.  What they are saying is that the temperature values (the numbers) are not worth anything, and that you should judge the image as it changes with the slider.  From the Phase One forum (The bold bits I have highlighted myself):

"The Capture One color temperature scale is not really a a meter of color temperature, but rather a color temperature adjustment scale that references color temperature principles. Because each camera capture light differently the same color temp value in CO4 will look different in the file. For instance if the actual measured color temp of a scene is 5500K one camera might reproduce correctly at 6300 in CO4 and another at 4800. The preset values you see are the balances from the camera converted to CO4 equivalent numbers."

"It would be great if Digital cameras used built in color temperature meters to analyze proper color balance, however this is not the case. Instead color is often determined by neutralizing the highest values (this is an overly simple explanation for sure). In this way each camera operates different producing different values which are later assigned. If we were working with only one camera and one CCD it would likely not be to difficult to produce a relatively accurate color temperature scale, but of course this is not the case. "

"I think your main point is that given this problem, why use the scale at all?? Well essentially we use it because it is how most photographers are accustomed to thinking about color. It provides a nice frame of reference. I remember some of our competitors used RGB adjustments at one point, and after many requests from photographers and digital techs moved to a Kelvin scale in more recent software releases."

This sounds crazy to me.  The camera doesn't measure the colour temperature as colour meter would have done?  I can see Phase One's point on this, but don't know why the camera manufacturers don't measure the actual colour value - all to a set standard (when I was at school the Kelvin scale was just that.  You didn't pick a colour temperature and drop it anywhere that you liked!).  And why can't the manufacturers all reproduce the temperature of a scene the same?

And if most photographers are used to thinking in this way then fine, but now this has been turned on it's head I don't see the point.  I mean, you don't go to a DIY store and buy a tin of paint that says "white" on it, only to get home and find that it is red.  The store manager wouldn't tell you "don't worry about what it says on the tin, it's the colour on your wall that matters". 

So now I have to remember that 6500K is fine for my ORF files but it's 4400K for the NEF.

I understand about colour temperature and white balance (at least I thought I did).  But I do find this a strange thing for the manfacturers of cameras to omit and the manufacturers of software to then include.

Here's hoping that someone can explain it for me   It's not critical, just something that I've been curious about for a while now.

 

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Just bumping this one up a bit hoping for a response

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"So now I have to remember that 6500K is fine for my ORF files but it's 4400K for the NEF."

I'm sure I read somewhere that Nikon would not release its NEF white balence code to other software companies with the result that reading white balence setting in another converter resulted in a less than perfect result..could this have something to do with it.

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Paul
My glass is 4/3rds full :)

MY GALLERY

You do wonder at the attitude of some manufactures. You'd have thought that they would want their product to produce the best images - and they must know that people won't all want to use their own software - so why hide the formula. One thing to hide some of the details, like the focus point in use on Canon cameras - as its not important. But to hide the WB data just seems plain daft.

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Mark

Digital Photo Group
My Website

Ne nuntium necare

Sounds like you ought to be starting a petition Mark which we can all contribute to. Or, how about DCM doing it - after all, it's a bit more straight forward than the Photography and the Law undertaking they have now. It's also of direct relevance to all digital photographers as without software we're all well and truly stumped. The AA and RAC plus continental equivalents stick up for their members so why not photography magazines for photographers. How about it then DCM?

That sounds about right Crafty, and that would explain why cloudy shots taken with the Olympus show a colour temperature of aroud 6000k (as I'd expect).  Olympus have probably been more forthcoming with their data.

As Mark says I don't know why a manufacturer would do this for WB though.  The only reason I can think of is to persuade you to buy their software.  But why did they even design the camera that way? 

You wouldn't design a car with a spedometer that gave your own figures.  You'd start by thinking "we need to show the speed in this format".  How they record it and display it is up to the manufacturer (be it pick-up, geared, analogue, digital etc) but the final result is a standard.  I can't see why a camera manufacturer would decide not to follow a similar line.

Oh well.  I'll just judge the result by how the wind feels in my hair

 

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