Page 1 of 1

White balance numbers WAY off w/ P45

PostPosted: Sun Mar 05, 2006 3:56 am
by michaelefox
Using C1 windows v3.7.3 with the latest color patch.

I have a number of images taken outdoors on a P45, in the middle of the day, with a mostly clear blue sky. So, the color temperature should naturally be approx. 5500K (or higher because one is at an altitude of about 6500 feet) and the tint should be approx. 0.

But C1 displays a color temp of 2950K and a tint of -14. This numbers are just so far off as to be obviously and hugely in error.

However, I have some other images taken under strobes with a Nikon D2X. The color temp and tint values are 5350 and 3, respectively, which are very close to what I measure with my color meter.

So, it appears that C1 is having a problem interpreting the correct color temp from P45 images and not with Nikon images.

What's the deal?

PostPosted: Mon Mar 06, 2006 9:44 pm
by Keith Carpenter

The Kelvin value is off, at ~ 2000 K off in version 3.7.3

This will be fixed in forthcoming v3.7.4 in April.

In the meantime, White Balance can easily be adjusted in Capture One using neutral are within image, using a true gray card or Macbeth, and then set for all Session images. A custom WB can also be created in Capture One and uploaded to the Pback.

See Knowledge Base article: ... nguageID=1

And Tips&Tricks: ... lance.aspx

k c

PostPosted: Mon Mar 06, 2006 10:27 pm
by michaelefox
Thanks. That's good news.

But what about the tint value? A value of -14 for a mid-day, clear blue sky shot is not close to correct either. Will that also be fixed in 3.7.4?

Thanks again,

PostPosted: Tue Mar 07, 2006 9:20 pm
by Keith Carpenter
yes, will certainly expect the Tint values to 'Behave' as well in 3.7.4...

k c

PostPosted: Tue Mar 07, 2006 9:33 pm
by michaelefox
Great. Thanks.

Color Correction between P25 and P45

PostPosted: Tue Mar 07, 2006 9:38 pm
by MikeR1
I have updated the software.

When doing corrrections using a color checker on a still set, the readings i get from for the P25 file vs. the P45 file using the same color checker make the image color different. The P45 look a bit more red.

PostPosted: Tue Mar 07, 2006 9:49 pm
by Keith Carpenter

Confirm that this result is with the Color Patch for P45 and Firmware update of 1.9.4 with PAVR of 1.0.3

k c


PostPosted: Tue Mar 07, 2006 9:58 pm
by MikeR1
Unless there is something I missed. The firmware has been updated and the color patch installed according to the instructions from the download site. I just showed my boss the differences and he sees it as well.