[darktable-user] White balance temperature
Can someone explain to me darktable's colour temperature settings in the white balance module. I thought with colour temperature, the greater the value the "colder" the picture will be - but in darktable it's the direct opposite. For example, if I move the slider from 5000K to 6000K I expect the picture to look cooler, but instead it became warmer. Why is this happening in darktable? -- cheers, Swee darktable user mailing list to unsubscribe send a mail to darktable-user+unsubscr...@lists.darktable.org
Re: [darktable-user] White balance temperature
Hi, Try a simple experiment : set your camera WB to tungsten, and take an outside picture. Get the JPEG from the camera. It will be blue... so too cool. It is the same in the raw processor, if it is an exterior daylight SCENE (quite neutral : 5500-6500K) and you set a warm colour temperature (3000K) for the PICTURE, it will appear be too cool. The behaviour is normal: you have to "compensate" so act the opposite as what you see. You tell the system the temperature YOU decide the SCENE was et not the temperature you would like the PICTURE appears. Jean-Luc 2016-03-30 13:12 GMT+02:00 Swee Oon : > Can someone explain to me darktable's colour temperature settings in the > white balance module. I thought with colour temperature, the greater the > value the "colder" the picture will be - but in darktable it's the direct > opposite. For example, if I move the slider from 5000K to 6000K I expect > the picture to look cooler, but instead it became warmer. Why is this > happening in darktable? > > -- > cheers, > Swee > > > > darktable user mailing list to unsubscribe send a mail to > darktable-user+unsubscr...@lists.darktable.org > darktable user mailing list to unsubscribe send a mail to darktable-user+unsubscr...@lists.darktable.org
Re: [darktable-user] White balance temperature
The color temperature refers to the color of the light used to illuminate the scene, not the color temperature of your final output. Darktable then compensates to make the colors look neutral. So the slider is saying "the light in the scene was 5000 K" or "the light in the scene was 6000K." If the light went from 5000 to 6000, darktable needs to "warm up" the image to compensate. There's another problem here: blue light looks "cool," red light looks "warm," to us. But higher black body temperature (the 6000K number) corresponds to bluer light. So there's a disconnect between the scientific meaning of "light from a cool source" vs. the psychological interpretation of "cool-looking light." -Owen On Wed, Mar 30, 2016 at 6:38 AM, Jean-Luc Coulon (f5ibh) < jean.luc.cou...@gmail.com> wrote: > Hi, > > Try a simple experiment : set your camera WB to tungsten, and take an > outside picture. Get the JPEG from the camera. It will be blue... so too > cool. > > It is the same in the raw processor, if it is an exterior daylight SCENE > (quite neutral : 5500-6500K) and you set a warm colour temperature (3000K) > for the PICTURE, it will appear be too cool. > > The behaviour is normal: you have to "compensate" so act the opposite as > what you see. You tell the system the temperature YOU decide the SCENE was > et not the temperature you would like the PICTURE appears. > > Jean-Luc > > > 2016-03-30 13:12 GMT+02:00 Swee Oon : > >> Can someone explain to me darktable's colour temperature settings in the >> white balance module. I thought with colour temperature, the greater the >> value the "colder" the picture will be - but in darktable it's the direct >> opposite. For example, if I move the slider from 5000K to 6000K I expect >> the picture to look cooler, but instead it became warmer. Why is this >> happening in darktable? >> >> -- >> cheers, >> Swee >> >> >> >> darktable user mailing list to unsubscribe send a mail to >> darktable-user+unsubscr...@lists.darktable.org >> > > > > darktable user mailing list to unsubscribe send a mail to > darktable-user+unsubscr...@lists.darktable.org > darktable user mailing list to unsubscribe send a mail to darktable-user+unsubscr...@lists.darktable.org
Re: [darktable-user] White balance temperature
Another explanation: the white balance slider should indicate the colour temperature of the ambient light. The module then should make white look like actual white. Therefore, if you set the temperature high, indicating that the light temperature is very high (whites look blue), then Darktable will compensate in the reverse direction to make the white look white instead of blue. On 16-03-30 07:12 AM, Swee Oon wrote: Can someone explain to me darktable's colour temperature settings in the white balance module. I thought with colour temperature, the greater the value the "colder" the picture will be - but in darktable it's the direct opposite. For example, if I move the slider from 5000K to 6000K I expect the picture to look cooler, but instead it became warmer. Why is this happening in darktable? -- cheers, Swee darktable user mailing list to unsubscribe send a mail to darktable-user+unsubscr...@lists.darktable.org darktable user mailing list to unsubscribe send a mail to darktable-user+unsubscr...@lists.darktable.org
