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02-15-2015, 01:39 AM   #1
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Auto WB errors

Hi Everyone.
I have noticed that the AWB is not accurate in the shades or under cloudy skies? It gives a strong blueish cast. The "shade" or "cloudy" preset give some orange cast which is not so good as well... Is it fixable in-camera? I'm shooting in RAW (DNG)

02-15-2015, 02:06 AM   #2
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QuoteOriginally posted by Odisseus Quote
Hi Everyone.
I have noticed that the AWB is not accurate in the shades or under cloudy skies? It gives a strong blueish cast. The "shade" or "cloudy" preset give some orange cast which is not so good as well... Is it fixable in-camera? I'm shooting in RAW (DNG)
That's only the JPG preview you're seeing. In PP you'll fix it however you like, including area by area if you have different light sources - bluish flash, yellow street light, etc.
02-15-2015, 07:42 AM   #3
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QuoteOriginally posted by clackers Quote
That's only the JPG preview you're seeing
Are you saying that the quick preview after shot is converted to JPG and thus all respective JPG settings are applied which I deliberately ignore while shooting in RAW? I'm sorry, it does not make much sense to me. I dont think that the developers are stupid enough to waste the system resourses on useless conversion of this kind.
QuoteOriginally posted by clackers Quote
In PP you'll fix it however you like
I certainly realize that, but the question is how to prevent it from happening if possible. Of course manual is better, but sometimes AWB is just more convenient.
02-15-2015, 08:05 AM   #4
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QuoteOriginally posted by Odisseus Quote
Are you saying that the quick preview after shot is converted to JPG and thus all respective JPG settings are applied which I deliberately ignore while shooting in RAW? I'm sorry, it does not make much sense to me. I dont think that the developers are stupid enough to waste the system resourses on useless conversion of this kind.
That's exactly what they do. These JPEG settings (WB, contrast, brightness etc.. ) are irrelevant to the underlying raw. Most of these settings will be ignored in a 3rd party raw converter, WB is the only one that attempts to get transferred (not always faithfully), but you can losslessly change the WB setting of a RAW file for a different interpretation of the captured data..

You can test it yourself, in raw mode take the same photo twice using manual white balance set to opposite extremes (preferably on a tripod). On the back of the camera, one preview will be very orange, the other very blue. Load both raw's into a converter and set them to a common WB. They'll be identical (up to camera movement, changes in light, etc.). You can do the same test with the other jpeg settings, and you'll get the same result.

Can't help with poor AWB performance though, sorry. I usually just stick to daylight for consistent previews and batch convert the WB to what I want in lightroom.

02-15-2015, 08:48 AM - 1 Like   #5
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QuoteOriginally posted by Odisseus Quote
Are you saying that the quick preview after shot is converted to JPG and thus all respective JPG settings are applied which I deliberately ignore while shooting in RAW? I'm sorry, it does not make much sense to me. I dont think that the developers are stupid enough to waste the system resourses on useless conversion of this kind.
RAW files aren't viewable photos, they're a collection of colorless pixels along with information about which section of the bayer filter was located at each pixel. Since it's colorless, it doesn't actually have any white balance. It's up to the RAW processing software to interpolate what color each pixel is supposed to be.

However each RAW file includes a really poor quality embedded JPG snapshot, so that you can browse through your RAW files without having to develop each one. It's a very low quality JPG snapshot, lower quality even than the lowest JPG quality available on your camera. THIS is what you're seeing when you review RAW photos on your camera. If you use RAW+ instead, then you'll be shown the full JPG photo on your camera rather than the crappy snapshot stored in the RAW file. So yes, the camera does "waste system resources on useless conversion of this kind" when shooting in just RAW (as you so kindly put it).

This snapshot DOES have a white balance value applied, and this white balance value is also stored separately in the RAW file as a reference for whatever RAW processing software you use to develop the file (called "As Shot" by most software). It's only a guideline and has no effect on the final output of the photo: you can choose whatever white balance value you desire in post processing.
02-15-2015, 10:32 PM   #6
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If you are using Lightroom to post process your RAW (DNG) image, here's a WB tip (or two) at about 2:40...

"The Lightroom Show" is On The Air! - Lightroom Killer Tips

Cheers... M
02-16-2015, 08:58 AM   #7
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QuoteOriginally posted by GoremanX Quote
each RAW file includes a really poor quality embedded JPG snapshot
I did not realize that, you've opened my eyes, thank you That explains a lot.
QuoteOriginally posted by BrianR Quote
I usually just stick to daylight
OK, so the bottom line is not to rely much on AWB. In this case how to see what light conditions will be to match the "shade" or "cloudy" preset? I mean how cloudy the sky has to be to apply one of those? I would appreciate some examples.
Michaelina2, good one, thank you!
02-16-2015, 01:54 PM   #8
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QuoteOriginally posted by Odisseus Quote
Hi Everyone.
I have noticed that the AWB is not accurate in the shades or under cloudy skies? It gives a strong blueish cast. The "shade" or "cloudy" preset give some orange cast which is not so good as well... Is it fixable in-camera? I'm shooting in RAW (DNG)
No, I have not seen that.


Steve

02-17-2015, 12:09 AM   #9
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QuoteOriginally posted by GoremanX Quote
However each RAW file includes a really poor quality embedded JPG snapshot, so that you can browse through your RAW files without having to develop each one. It's a very low quality JPG snapshot, lower quality even than the lowest JPG quality available on your camera. THIS is what you're seeing when you review RAW photos on your camera. If you use RAW+ instead, then you'll be shown the full JPG photo on your camera rather than the crappy snapshot stored in the RAW file. So yes, the camera does "waste system resources on useless conversion of this kind" when shooting in just RAW (as you so kindly put it).
I dont think this is exactly true - if you open a raw file in irfanview (for example) it shows the embedded preview unless you disable that in the options settings. This is a perfectly fine full resolution jpeg with all the settings applied, at least it is when shooting raw in DNG format. It might be somewhat lower quality than the camera would save in jpeg mode but it is by no means "really poor".
02-17-2015, 10:48 AM   #10
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Will this be OK for a "Cloudy" preset or is it still more or less clear sky and the "daylight" can be used?
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The same question. What preset to use with this sky? (Sry, not much of a sky... but it is right before the rain)
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02-17-2015, 01:00 PM   #11
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QuoteOriginally posted by rfg Quote
I dont think this is exactly true - if you open a raw file in irfanview (for example) it shows the embedded preview unless you disable that in the options settings. This is a perfectly fine full resolution jpeg with all the settings applied, at least it is when shooting raw in DNG format. It might be somewhat lower quality than the camera would save in jpeg mode but it is by no means "really poor".
I think "poor" as in "not full resolution". Try zooming in on the preview and see if the viewer doesn't have to think for a bit before being able to show you a sharp image.

Anyway that's how it looks to me.
02-17-2015, 01:26 PM   #12
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I'd use daylight for the top, cloudy for the bottom, then fine-tune in post.

If you were using a flash in full shade, you'd put an orange gel on it for similar reasons. :-)
02-17-2015, 02:30 PM   #13
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Looking at the examples, you've just shown why we shoot in RAW in the first place. If Auto-WB was spot on every time or could be, I'd probably never even bother with RAW.

I have noticed that with the K-3, the auto-white balance isn't as great as it was with the K5, but I don't really find it bad either. I do see that it looks better when I use the multi-white balance, but LR can't utilize that setting, so I'm not sure if the resulting WB would be better.

What I do notice is that when I'm in LR, the K-3's auto-white balance is still better than the auto that LR tries to use when I'm processing. I usually just stick with the auto white balance in the camera and then manually adjust the numbers if needed. I think I generally always find myself needing warmer settings when there are clouds or shade, so I just tweak things as needed. The presets in any software don't ever seem to be quite right except perhaps the sun settings.
02-17-2015, 04:21 PM   #14
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I disagree. I find the K-3 AWB to be superior to any of the previous K series cameras.
02-17-2015, 10:37 PM   #15
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QuoteOriginally posted by jbinpg Quote
I disagree. I find the K-3 AWB to be superior to any of the previous K series cameras.
I agree with this - mostly I am happy with the K-3 AWB. Sometimes I do need to tweak a bit, and maybe half of those times the LR auto WB will be an improvement.

QuoteOriginally posted by savoche Quote
I think "poor" as in "not full resolution". Try zooming in on the preview and see if the viewer doesn't have to think for a bit before being able to show you a sharp image.

Anyway that's how it looks to me.
No definitely full resolution (6016x4000) preview. If I uncheck the "user embedded preview" option it takes WAY longer to load the image (like 10 seconds vs less than 1).
Actually looking at the data the preview is slightly lower res - the rendered raw image comes in at 6028x4024. Weird...
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