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View Full Version : Whitebalance, and the #1 reason to use RAW



arthurking83
14-01-2009, 12:12pm
As we all know, and it's reiterated time and again that shooting in RAW mode gives you the greatest latitude for developing an image further, with the greatest of ease and retain as much quality as possible.
Sometimes you may not have the time to suit such an involving workflow as there may be more steps in the processing stage and if you have hundreds of images to develop it all takes time. If you are at that stage then you're probably making money from photography and this 'tutorial'.. more of an infotorial than a tute! is for those mad keen amateurs that just can't seem to get enough decent exposures in a single day! (me!! :p)

My main reasons for using RAW mode is the ease of which you can set WB in software on the PC, which makes one less thing to stuff up at the time of exposure. There are many other reasons to use RAW(and my other main reason is to save file space on the PC if I edit a shot, AND want to keep the original intact... with most RAW images(that I know of) if you edit the original you don;t need to keep an edited copy AND the original, as they are one and the same, and all edits can be undone later and hence you still keep the original file. There's no need to keep multiple 20Meg files(and for me at 250gigs of images now that's quite a bit of space!!)

Setting WB on the PC later is exactly the same as setting it on camera at the time of exposure. I confirmed this with a two shot set after I took this image in AWB mode, where I set the WB on camera to Shade. the original looks totally YUK!! even on th etiny puny D300 screen, and I thought to see how WB set manually would come out. I have a WB card to be able to set it more accurately, but in this scene I knew what setting was going to be more appropriate, and at the time, given the conditions I was in, Shade was exactly as the scene was, and I remember that as I was standing there trying to get a more accurate representation of what the scene should look like.
reference to CNX is Nikon's CaptureNX, and ViewNX works equally at setting WB on Nikon NEF's. Nikon apparently encrypt WB settings in camera, so other third party software may render WB differently. It shoudln;t as you;re simply adjusting colour temperature to known values.. but I don;t delve deeply into these things nor do I care.. If you're suing Nikon and shoot NEF, at the least try ViewNX as your initial RAW to raster image converter if you are unsure. Other cameras may work differently.

So the white balance issue for me is:

1. Auto WB ie. as the camera sees it
http://www.ausphotography.net.au/gallery/files/1/0/wb-a_dsd_8930.jpg

2. Daylight(5200K)
http://www.ausphotography.net.au/gallery/files/1/0/wb-dl_dsd_8930.jpg
Whoa! way too blue for daylight as there was no yellowing/warming sun to balance so much blue rendering.. makes sense!

3. Cloudy(6000K)
http://www.ausphotography.net.au/gallery/files/1/0/wb-cl_dsd_8930.jpg
looks exactly the same as Auto. The camera obviously thinks I'm in a cloudy scenario, and set WB accordingly. on the face of it I wouldn't cared too much, and many people would have just accepted the image, but as I was there and I had an immediate visual representation to work with, I still immediately thought it looked too blue....

4. Shade(8000K)
http://www.ausphotography.net.au/gallery/files/1/0/wb-sh_dsd_8930.jpg
There! that;s what the scene looked like as I remember at the time when I made the exposure with WB set to Shade.
This isn't the actual image I made in WB Shade mode. It's the original Auto WB shot, but with only the WB adjusted using CNX, as all th eother image have been processed. It's exactly the same colour balance as the next shot, with WB manually set to Shade, on my PC as I see it, and the histogram is the same shape. So setting WB later on the PC is for all intents and purposes the same as setting it on the camera.

Here's the same image(as WB Shade above) set to WB Shade, but with Picture Control setting set to Standard.
6.
http://www.ausphotography.net.au/gallery/files/1/0/wb-sh-pcstd_dsd_8930.jpg

The previous image had PC set on camera to Vivid -1Contrast, which I think gives about the best colour contrast rendition, but this one was set to Standard and nothing else except the same sharpening level (6??.. I forget!).
It doesn't look bad and at least all the red looks red, but much more flat that I saw at the time(and why I made a point to set WB manually in this particular shot!
Having barely any red in the image, invited my curious nature to do this comparison.
As I saw it the best rendition of the scene, both on camera and later on the PC is that #5 image.
#6 is almost OK, and much less greeny-blue when compared to that #1 AWB shot.
Lots of folks have commented on my images having too much colour(too vivid), and that's certainly a product of setting the camera up with Vivid Picture Control.
I have tried Standard with saturation +1 and it's almost the same, but I think we all see colour differently relative to each other, and I have previously commented in another thread that I tend to wear polarised sunnies almost always, and this affects th ecolour that I see, which is always vivid. I base my need to stop and take a photo purely on that fact that I wear these sunnies, and tilt my head side to side to see how much effect polarising a scene will have.
But in this situation, deep into a tropical rainforest valley with barely any sun coming directly through the forest I wasn't wearing those sunnies.
Not only that, but there was a lot of brown dying/dead plant matter which may have affected the WB a little as well, plus the fact that whatever sunlight was filtering through was warmer than it would otherwise have been at say midday.

I find that for WB the first and last 3 or 4 hours of the day are hugely affected by colour of sunlight, where I may set up to 800K more than standard Sunny 5200K to get the colour temperature right on.
Between approx 10AM and 4PM in summer, and it's going to vary for each season and lattitude!... Sunny 5200K is perfect on bright sunny days.

This isn't really a tute on setting WB or how it's affected. It's more about the importance of how getting WB right or wrong(whether on camera or on PC) can affect the overall quality of an image.

And finally adjusting WB affects the histogram, which affects the actual exposure. Many times I've seen a slightly blown highlight, that came good by simply adjusting WB to suit.
It always seems to be in the red channel too
That's not to say by blowing out a highlight you can recover it in PP by setting WB :p

OK. that's it!.

If you feel a need to add something or correct me on any mis-information I may have presented by all means do so.. as I'm keen to learn what others know about WB and it's overall impact on IQ.

I'm happy with AutoWB on camera as it;s just one less thing to have to stuff up, if you get it wrong, usually in variable lighting conditions such as a forest at late/early hours ;)
I should try to remember to take my WB card with me more often, though! :p

EDIT: relinked images.

MarkChap
14-01-2009, 1:58pm
Well put together and presented Arthur, certainly gives some food for thought

Well Done

kiwi
14-01-2009, 2:42pm
Nice tut. Good examples.

I would wonder though whether AWB is bad thing all the time. I'm coming to the slow and painful conclusion that I should (short of presetting etc) pick instead a AWB preset (eg cloudy) and stay with that while the light in constant. It usually closer and its certainly a lot easier to bulk edit JPG's anyhow ?

MrJorge
14-01-2009, 3:21pm
Agree this is a cool little example. I must admit I too leave AWB on constantly and use Lightroom to fix it up. Normally in Lightroom I find the "Auto" white balance setting fixes images the best. Sometimes I've used one of the others but mainly "Auto".

I guess it is better, like everything, to get this right when you take the shot as it means you don't have to edit it later Daz. Especially if you're shooting a lot of images in the same lighting, you'll probably save a bunch of time by getting it right first.

It's just not something that is in my active thought process enough yet. It might get into there one day though :p

I can't see any reason against AWB all the time except for the concept of not getting it right at the time and having to spend time later fixing it.

kiwi
14-01-2009, 3:52pm
Agree this is a cool little example. I must admit I too leave AWB on constantly and use Lightroom to fix it up. Normally in Lightroom I find the "Auto" white balance setting fixes images the best. Sometimes I've used one of the others but mainly "Auto".

I guess it is better, like everything, to get this right when you take the shot as it means you don't have to edit it later Daz. Especially if you're shooting a lot of images in the same lighting, you'll probably save a bunch of time by getting it right first.

It's just not something that is in my active thought process enough yet. It might get into there one day though :p

I can't see any reason against AWB all the time except for the concept of not getting it right at the time and having to spend time later fixing it.

My experience is that despite the fact that the light looks the same, it's not between shots, and therefore setting AWB in camera is not setting a consistent WB reading making for possible problems in batch processing. Setting WB by doing a preset (using a reading, or Expodisc) is the best bet, followed by choosing the nearest likely camera setting (eg cloudy, sunny etc).

You have better luck with LR auto than I do.

MrJorge
14-01-2009, 4:20pm
My experience is that despite the fact that the light looks the same, it's not between shots, and therefore setting AWB in camera is not setting a consistent WB reading making for possible problems in batch processing. Setting WB by doing a preset (using a reading, or Expodisc) is the best bet, followed by choosing the nearest likely camera setting (eg cloudy, sunny etc).

You have better luck with LR auto than I do.

Yeah you're right about that. Especially outdoors shooting sports etc it can change rapidly and you don't want to be sitting there constantly wondering if you've got the right WB dialed in. Another reason I always leave it on AWB.

As for LR Auto being more successful for me I guess it's possible my camera aligns better to what it thinks is "Auto" than yours or something. :confused013

arthurking83
15-01-2009, 12:30am
..... Setting WB by doing a preset (using a reading, or Expodisc) is the best bet, followed by choosing the nearest likely camera setting (eg cloudy, sunny etc).

......

I find that it makes no difference to the (RAW)image which Auto preset you choose, as whatever subsequent setting you use in PP, it always looks better if you 'guess' it correctly at the batch process stage. I like ViewNX1.2.2 for that purpose for Nikons.
So if I use a preset of Direct Sunlight all the time, during both the midday sun and in the shade of a deep dark rainforest at near sunset, it wil be obvious which images need adjusting anyhow and I'd batch them images only with a more correct WB.

I've seen a 3 exposure bracket sequence go all weird on me with WB. That is, in the space of about 0.6 seconds between shot 1 at standard exposure and shot 2 at -0.7EV, the D300 decided that AWB was more direct sunlight than shady!! :confused: .. and that shady was more appropriate again for the +0.7EV exposure!! :p

A while back I found myself in an old bluestone ruins, and the light was constantly changing between sunny and cloudy, but that it was closer to sunset than midday. The bluestone surrounds made AWB an interesting proposition for the camera to try to make sense of the proper whitebalance, and it looked all wrong from the beginning. I used my grey card and preset one WB figure. After a while of course the sun came back out and WB looked all wrong again, so I reset another Pre WB, and logged that into memory too. I now had two Preset WB settings and there wasn't any need for any more unless I was going to stay for another two hours as the sun set and changed the color of the light significantly.

Setting any of the Direct sun/Cloudy/Shade WB settings were close, but not correct as the bluestone surroundings affected the overall colour balance too. So Presetting WB was the best choice here. This is true of mixed lighting conditions too, where you may have fluoro and flash or fill flash(without filters) and sunlight.... etc.
one thing I have almost always noticed is that mixing incandescent(tungsten) and fluoro lighting always produces a green tint with AWB, that can't be adjusted for easily with any 'preset' WB setting, and needs hue(which Nikon now calls Tint) adjustment.
So there's more to WB than just colour temp, hue gets mixed up the equation too.

One of the points I did make was for the photographer that this info did not cater for... and that was the likes of Kiwi(Darren) :p
LOL! I did make this infomercial for us casual amateurs that have all the time in the world to set and reset and make adjustments as we see fit, rather than be constrained to the pressures of timelines and deadlines!
I have no experience with shooting sports or events of any kind where I have hundreds if not 1000's of images to process, or shoot as jpgs.
In that case I''d be shooting RAW and JPG mode, and one of each type to each separate card(only a guess, as I don't do it, so I have no experience!!)
I'd take a moment to set WB using a grey or white card and log that into memory(Nikons Dx/Dxxx should have 4, at the least)
Also, I remember reading that the Dx series had very good AWB due to it's dedicated WB sensor on the prism housing.. which looks to have disappeared on the D3
Looking at the specs, the D2 series had an hybrid 'ambient' sensor(small white dot on the prism housing) and the D3 only seems to use the 1005pixel AF sensor!!
I'm wondering why Nikon would make a backward step like that rather than improve on it somehow? Probably doesn't make a big difference but it would sure make a pro's life a lot easier, huh? :D

ps. those energy saver light globes are a nightmare sometimes!! I'm curious as to what some folks have tried for WB settings, either on camera or in PP. They're not quite incandescent, nor fluoro, but certainly a pain in the WB sensor! :D

Dan AU
16-01-2009, 1:21pm
Good tips, I found this with my recent seascape, low light shots, I think I had left them on daylight and they all turned out very blue. In using Canon's DPP I adjusted to Shade and they all turned out looking so much more natural.

overvisa
04-11-2010, 1:39pm
thanks arthurking83, I've learnt a lot more from your tutorials.