How White Balance settings work - DPChallenge Forums

Canon RF 24-70mm f/2.8 L IS

12/18/2012 09:55:08 PM · #1

So, to start things off, I know about changing WB for my needs and have done it to change how my photos have looked for various shots as well as setting it appropriately to get an image that replicates reality.

The problem is, I saw a comment on this Strobist post from Brian McCarthy that got my head wondering. Basically, he said that the various WB settings on a camera were not actually absolute settings but were still evaluating the scene, which caused him a problem.

So, I did some digging, found the source I think he was referencing (found here), and now I'm wondering if other mfg's do the same or if anybody else had experience/issues with this?

kirbic

Canon EOS R5

12/18/2012 10:29:29 PM · #2

All camera manufacturers do approximately the same thing. Per the Canon page you referenced, the two that allow you to lock it down are Kelvin and Custom. With these, the WB is set and does not change shot-to-shot.
Of course, if you are shooting RAW, none of this really matters, since it does not affect the RAW data.

Canon RF 24-70mm f/2.8 L IS

12/18/2012 10:45:57 PM · #3

Originally posted by kirbic:

Sure thing about RAW and it being largely irrelevant, but it still increases workload (albeit only slightly) if you need to change the white balance that you've set. I usually just leave my WB on auto and figure it out later as a result, but if I set it (for studio/flash work, say) I expected it to be, well, SET.

I figured other mfg's would be the same, but do you have any idea how much latitude we are talking here?

kirbic

Canon EOS R5

12/18/2012 10:55:11 PM · #4

Originally posted by spiritualspatula:

I figured other mfg's would be the same, but do you have any idea how much latitude we are talking here?

Very moderate, a small fraction of the difference between the major settings. They are using this mostly to balance out a tint, e.g. a tendency toward green due to foliage reflection. We can't always think of the adjustment as equivalent to, say, +100Â°K, because it might not be a simple "make it cooler" (or warmer) adjustment.

Originally posted by spiritualspatula:

...if I set it (for studio/flash work, say) I expected it to be, well, SET.

Me too. I use a Kelvin setting or shoot a gray card, and then I know what I've got. Well, in casual situations I still mostly do what you do, leave it on Auto because I really don't care what it is. Only real advantage of the more precise setting is a better display on the LCD.

PGerst

Canon EOS-20D

Tamron SP AF 28-75mm f/2.8 XR Di for Canon

12/18/2012 10:56:54 PM · #5

The fork is actually silver and the backdrop was blue. This was far more interesting from a color perspective than the appropriate white balance.

So, while I understand the desire to set white balance, I think in this case I would have missed something good and the flexibility in any shoot is probably worth the RAW workflow.

Originally posted by spiritualspatula:

Canon EF-S 18-55mm f/3.5-5.6 IS

12/18/2012 11:14:14 PM · #6

Originally posted by PGerst:

But if you want consistency, or if you're evaluating your setup, that doesn't work as well since you
A: need to see how your changes are changing the scene
B: have final images that meet your desired outcome

So I guess what the question becomes is what is the best approach to get this. Should I just set a custom WB for my speedlights and save it, or gray card each time? I assume my SB's are pretty much the same, but I don't think my ABR800 is as consistent, so using those together might pose a problem...

Also, question for Kirbic-
You said it's to correct for casts, but wouldn't that INCREASE their existence? What I mean is... you have a green scene, the camera sees lots of green, compensates, makes non-green things (like people) magenta. If it had a defined set K value, that couldn't happen, no?

GAP2012

Canon EOS-550D Rebel T2i

12/18/2012 11:21:58 PM · #7

Originally posted by PGerst:

I have yet to change my WB settings from auto. I experimented a few times with adjusting it in camera and never found the use over RAW.

Here is a perfect example of why, and although its not a human model, the effect was just the same.

In this challenge image I shot RAW but this was the result I got from the auto setting:

The fork is actually silver and the backdrop was blue. This was far more interesting from a color perspective than the appropriate white balance.

So, while I understand the desire to set white balance, I think in this case I would have missed something good and the flexibility in any shoot is probably worth the RAW workflow.

Originally posted by spiritualspatula:

Sure thing about RAW and it being largely irrelevant, but it still increases workload (albeit only slightly) if you need to change the white balance that you've set. I usually just leave my WB on auto and figure it out later as a result, but if I set it (for studio/flash work, say) I expected it to be, well, SET.

I figured other mfg's would be the same, but do you have any idea how much latitude we are talking here?

it would make a difference if you shot it in raw but need to use it in the minimal and basic challenges, and if you use a grey card with people even in raw you at least get a better photo when you shoot and look at either raw or jpeg version... just something worth considering, even though i shoot in both i tend to change it to my conditions out of a matter of part of the process and not leave everything upto the camera but try to do as much of it myself so that i can get some degree of understanding of how close it should be to the final image... its not a bad thing to switch off the auto settings of a camera as much as possible and do the work yourself where possible imho

GAP2012

Canon EOS-550D Rebel T2i

Canon EF-S 18-55mm f/3.5-5.6 IS

12/18/2012 11:29:54 PM · #8

plus the WB on a canon and any manufacturer is not 100% anyway they are slightly below or above the K theyre quoting for that WB, so set it and where you can say with a grey card for in portraits you'll get a better result... and in other scenes choose the nearest for the condition or use custom and then in raw you can tweak and see how close you got it for referencing later

MinsoPhoto

Canon EOS-7D

Canon EF 50mm f/1.4 USM

12/19/2012 07:34:20 AM · #9

Get a grey car and shoot that at the beginning and every time you move to where the lighting changes. You can batch the wb in LR to the grey card and will get you a solid starting point which you can tweak from there.

Bear_Music

Samsung Galaxy S24 Ultra

Sony 24-70mm F4 Vario-Tessar T* FE OSS

12/19/2012 11:34:48 AM · #10

Originally posted by MinsoPhoto:

Get a grey car and shoot that at the beginning and every time you move to where the lighting changes.

That's an awesome idea. I'll paint my white Ford Escape to a zone-5 gray and I'm good to go, anywhere! I'll need a bigger door into the kitchen though; I shoot a lot in there :-)

MinsoPhoto

Canon EOS-7D

Canon EF 50mm f/1.4 USM

12/19/2012 12:08:28 PM · #11

Originally posted by Bear_Music:

Originally posted by MinsoPhoto:
Get a grey car and shoot that at the beginning and every time you move to where the lighting changes.

That's an awesome idea. I'll paint my white Ford Escape to a zone-5 gray and I'm good to go, anywhere! I'll need a bigger door into the kitchen though; I shoot a lot in there :-)

lol, oops :)

EL-ROI

Canon EOS-450D Rebel XSi

Canon EF-S 18-55mm f/3.5-5.6 IS

12/19/2012 12:52:45 PM · #12

Nice one Mr. Bear!

I think if you are looking for consistency and you are that precise in your workflow, setting a custom white balance on scene and then programming your camera to use that white balance is the way to go. The workflow is either extra work in the field adjusting your camera settings or extra work in PP adjusting white balance settings. Either way there is work involed.

Devinder

Canon EOS-5D Mark III

Canon EF 24-70mm f/2.8L USM

12/19/2012 01:13:39 PM · #13

i've had similar issues and here's how i approach it.

I like consistency in my shots, but I also like to experiment with colors as i go. The biggest pain in the ass to get to a system i liked was to get my camera screen to agree well with my main working monitor. Once this was acheived, i knew what i saw would be atleast close to what i got.

i will either test shoot, either through eye piece or live view if no flash is involved(yeh frowned upon - but i get an emulated representation of the image for those non-flash assisted shots as i change through my Kelvin values and i like that)to get to a place i like in terms of temp. usually takes 2-3 shots to start. Once there, i m good to go. I shoot an occasionally look at the 1 second view you get in the LCD right after shots to make sure i m staying consistent (especially during transitions between rooms and close to golden hour). if i feel a shot is going in a direction i don't like I'll move the Kelvin up or down a couple hundred or as needed. A quick forward back between images on camera lets you remain relatively consistent and in situations where things are moving, and in static situations like studios with controlled lights, you tend to have full control anyway. I would keep in mind general guidelines for tungsten vs daylight, but other than that - full manual - allows you to avoid work later.

There are of course plenty of arguments to be made against full manual, but it works alright for me - its only getting better with practice.

edit: You can always gel flashes to compensate for types of lighting you expect to work in (different stengths of CtO/CTS/WindowGreen/CTB etc), but i would keep an eye on the images shot as you progress through your day. You can end up with overly exxagerated values across the board if your environment is changing.

Also My ABR is not super consistent, but don't really go too wild. I think between units you can expect as much as 300-400 Kelvin difference. I remember reading something along those lines on the Paul C buff site. I know my ABR's a bit warm to start with once they're settled in. I usually use the moon unit indoors which atleast gets me in a Ball park area that i like and modify as needed.

Grey cards, your palm, whibal units, color checkers, are all good tools for getting close to where you want to be, but i feel that some small variability between different flashes (especially when using different types of flashes in the same setting) are to be expected. Still, i think its safe to say that custom white balance is your friend.

Message edited by author 2012-12-19 13:33:35.

Canon EF 24-70mm f/2.8L USM

12/19/2012 02:07:52 PM · #14

Okay then, looks like I've got a few options. So, I've got a gray card, but was wondering if anybody had used either of these products-
Spyder Cube or the X-Rite Color Checker. Both function as basically hyper powered gray cards. I like the form factor of the cube- thing is so small I could easily throw it in my bag and never notice until I needed it.

Overall, I'm not this anal with WB, but frankly, if I'm putting forth that much effort during shooting to dial in, I might as well do it right and these two seem to do that with lots of control.

ETA:Devinder- do you have any speedlights with your AB's that you use side by side? I'm just curious if you've seen a difference between the two. I could just test my ABR but I know you have one so figured it was worth asking...

Message edited by author 2012-12-19 14:08:40.

Devinder

Canon EOS-5D Mark III

12/19/2012 02:22:02 PM · #15

i do and they are different. the ABR, is warmer i feel in comparison. I've compensated by sticking to use it for rim/highlight work in most cases.

The ABR gets heavy lifting for high contrast outdoor shots. Once in a rare while i'll use it as key light in conjunction with others speedlights if i've got no choice. One day i gelled it and a speedlight at 1/2 CTS (had to custom cut the gel because Paul C only sells CTO's and they're a bit reddish for me). THE moonlight was out and so was my 24 inch softbox. A third speedlight at 1/2 cts was ready to go but i ended up not needing it. I'll see if i still have that pic and post it if i do. Used a custom grey shot that day, worked out well.

Edit: I own an expo disc, which works alright (its accurate enough in most cases). I don't use it as often anymore. Its a nice tool to check out - but a bit expensive for what it does.

Message edited by author 2012-12-19 14:29:28.