Auto white balance in GIMP

K1TesseraEna · **Joined:** Sep 22, 2012 **Posts:** 2089 **Location:** US

Hi everyone!
When I take pictures with my DSLR camera I never worry about white balance setting on it
or use UV filter (rather than for lens protection purposes, perhaps) because I know I can do
all these adjustments later on while processing images in GIMP. However....

I've noticed that auto white balance adjustment in GIMP doesn't fully satisfy my needs
(subjectively, to my taste). I "discovered" that I can do it manually by picking with eyedropper
the brightest and darkest pixels on my image in Colors>Levels or by sliding and aligning the
handles in Linear or Logarythmic Histograms. Usually it brings better results, in my opinion.
Auto white balance in GIMP just sets it to the marginal values of 0 for black and 255 for white,
which are not always present in image. I compared the results in GIMP and PS, and the difference
is quite perceptible.

I know some folks here are real experts and pro photographers.
I wonder how you guys do white balance adjustment in GIMP. Are you using other applications
for the task?

Thank you all in advance.

paynekj · **Posted:** Thu Oct 04, 2012 1:44 pm **(#2)**

Because I'm getting RAW files out of my dSLR, I alter the white balance in my RAW processing software (Photivo in this case), although I do tend to subscribe to the idea of getting as much right in the camera as possible.

Kevin

anarkhya · **Posted:** Thu Oct 04, 2012 5:35 pm **(#3)**

Automatic processing is, by design, limited and you already touched this idea with your fine-tuning trial and error (auto white balance is one example among others), the way as I see it, auto white balance is mostly a kind of "your-easy-lazy-processing-that-usually-gives-acceptable-results". In a way, I could tell you that anything that doesn't place you in full control of the output is satisfactory on a short term only. Have you tried playing with the curves ? This is an intimidating but interesting area to explore (and a vast one).

ofnuts · **Joined:** Oct 25, 2010 **Posts:** 4812

K1TesseraEna wrote:

Hi everyone!
When I take pictures with my DSLR camera I never worry about white balance setting on it
or use UV filter (rather than for lens protection purposes, perhaps) because I know I can do
all these adjustments later on while processing images in GIMP. However....

Then you are mistaken. Take a sunset with the wrong white balance setting (or even worse, the "auto"
one) and you'll never get the real colors. If you never want to worry, use the "sunny day" setting, but it's better to use the relevant setting, to go manual (keep a Nutella lid (pure white plastic) in your bag to take the "reference" picture) or to use "raw" files.

Plus Gimp is currently a terrible tool for this because the 8-bit/channel limit very quickly creates artefacts and banding when doing color/contrast work. I do this with Digikam, and use Gimp for local editing or special effects.

K1TesseraEna wrote:

I've noticed that auto white balance adjustment in GIMP doesn't fully satisfy my needs (subjectively, to my taste). I "discovered" that I can do it manually by picking with eyedropper
the brightest and darkest pixels on my image in Colors>Levels or by sliding and aligning the
handles in Linear or Logarythmic Histograms. Usually it brings better results, in my opinion.
Auto white balance in GIMP just sets it to the marginal values of 0 for black and 255 for white,
which are not always present in image. I compared the results in GIMP and PS, and the difference
is quite perceptible.

I know some folks here are real experts and pro photographers.
I wonder how you guys do white balance adjustment in GIMP. Are you using other applications
for the task?

IMHO the best tool is the whitebalance script by Luca de Alfaro. Basically you use the color picker to set the foreground to the current color of anything in the image that should have been neutral gray, and use the "Make foreground gray" function.

K1TesseraEna · **Joined:** Sep 22, 2012 **Posts:** 2089 **Location:** US

Hi! Thank you all for responding!
I think today I've learned a couple of things from you guys, for that I'm really thankful.

anarkhya wrote:

Have you tried playing with the curves ? This is an intimidating but interesting area to explore (and a vast one).

I like experimenting with curves along with a collection of 50 or so acv PS curves that I have in GIMP. After watching a few tutorials on retrieving information from the over-/underexposed areas of an image using curves, it's hard to overestimate its potential.

ofnuts wrote:

Then you are mistaken. Take a sunset with the wrong white balance setting (or even worse, the "auto"
one) and you'll never get the real colors. If you never want to worry, use the "sunny day" setting, but it's better to use the relevant setting, to go manual (keep a Nutella lid (pure white plastic) in your bag to take the "reference" picture) or to use "raw" files.

I would rather agree with you, Ofnuts. My camera is Panasonic Lumix DMC-FZ200K and I think there's something wrong with camera's sensors or processor but I get the best quality pictures at dawn and sunset as well as on a cloudy day with white balance not set to relevant lighting conditions. I read about white balance lens cap but never used one. Now I think I'm going to.

ofnuts wrote:

Plus Gimp is currently a terrible tool for this because the 8-bit/channel limit very quickly creates artefacts and banding when doing color/contrast work. I do this with Digikam, and use Gimp for local editing or special effects.

IMHO the best tool is the whitebalance script by Luca de Alfaro. Basically you use the color picker to set the foreground to the current color of anything in the image that should have been neutral gray, and use the "Make foreground gray" function.

Already installed and tried the script. I like the results. Thanks!

K1TE

ofnuts · **Joined:** Oct 25, 2010 **Posts:** 4812

K1TesseraEna wrote:

Hi! Thank you all for responding!
I think today I've learned a couple of things from you guys, for that I'm really thankful.

anarkhya wrote:

Have you tried playing with the curves ? This is an intimidating but interesting area to explore (and a vast one).

I like experimenting with curves along with a collection of 50 or so acv PS curves that I have in GIMP. After watching a few tutorials on retrieving information from the over-/underexposed areas of an image using curves, it's hard to overestimate its potential.

ofnuts wrote:

Then you are mistaken. Take a sunset with the wrong white balance setting (or even worse, the "auto"
one) and you'll never get the real colors. If you never want to worry, use the "sunny day" setting, but it's better to use the relevant setting, to go manual (keep a Nutella lid (pure white plastic) in your bag to take the "reference" picture) or to use "raw" files.

I would rather agree with you, Ofnuts. My camera is Panasonic Lumix DMC-FZ200K and I think there's something wrong with camera's sensors or processor but I get the best quality pictures at dawn and sunset as well as on a cloudy day with white balance not set to relevant lighting conditions. I read about white balance lens cap but never used one. Now I think I'm going to.

ofnuts wrote:

Plus Gimp is currently a terrible tool for this because the 8-bit/channel limit very quickly creates artefacts and banding when doing color/contrast work. I do this with Digikam, and use Gimp for local editing or special effects.

IMHO the best tool is the whitebalance script by Luca de Alfaro. Basically you use the color picker to set the foreground to the current color of anything in the image that should have been neutral gray, and use the "Make foreground gray" function.

Already installed and tried the script. I like the results. Thanks!

K1TE

Technically an FZ200K isn't a DSLR (which would have a completely optical viewfinder) but a "bridge" camera. DSLRs also normally feature interchangeable lenses and a much larger sensor (about 16x more area than yours). There is likely nothing wrong with you camera, you just have to figure out its limitations and learn to cope with them.

White balance settings on cameras are designed to make the camera produce an image that has a gray average, so pictures with a dominant color at either end of the spectrum (especially red/orange sunsets) are washed out. High-end cameras are also often set by default to produce very neutral images that are easier to post-process (contrast/saturation/sharpness). It's a choice to make, either you produce more vivid pictures directly but they will be hard to retouch, or you produce pictures knowing that you'll post-process them. I have the JPEG settings for moderately vivid images, knowing that if I intend to post-process heavily (difficult lighting conditions) I'll switch to "raw" output anyway.