Welcome to the forum!

As an adjunct to the Tangents blog, the intention with this forum is to answer any questions, and allow a diverse discussion of topics related photography. With that, see it as an open invitation to just climb in and start threads and to respond to any threads.

need advice on Custom White Balance

dbrunodbruno Member
edited March 2015 in general photography
Hi - I'm getting different answers from different sources on this, and it really shouldn't be this ambiguous: when setting a custom-white balance with a grey card, to what white-balance setting do you set the camera when you take the shot of the card? One source says to set it to "custom", take the shot, and tell the camera to reference that shot. Another source says to set the white balance to whatever light you are shooting the card (tungsten, daylight, etc.), shoot the card, and tell the camera which shot to reference. A third source says to set it to auto, shoot the card, and tell the camera which shot to reference. Can anyone help clear this up? I have a Canon T3i, and know the procedure, but this initial part is a bit confusing.

Thanks.

Comments

  • TrevTrev Moderator
    edited March 2015
    Dave,

    The common and obviously correct way to obtain a good WB is to place the card directly in the type of light you are shooting, get your exposure right (that's important since under-exposing dramatically changes WB) take the shot and reference that shot as the Custom WB.

    Now, this means also if you are going to use flash, since flash is a light source, just like fluro, tungsten, sun, shade, sodium, whatever light source you are going to be shooting in.

    It's totally useless to set a CWB first, then add flash later for example.

    So, in short:

    1] Get correct exposure you wish to shoot at, including flash if used.

    2] Set the camera to Custom or whatever you need to do depending on your camera model.

    3] Place the Grey Card (usually white for Nikons I find the best), take the shot, then define that shot as your CWB.

    I mean, it's logical to do that and any other way is just plain stupid to put it bluntly.

    Don't forget, you need to get your exposure pretty spot on or how you want to shoot it first, since exposure most definitely will affect WB, especially when it's under exposed, it's very muddy.

    Also, make sure the card (whatever you use) fills at the very least 90% of the camera frame, you just cannot take a wide shot and expect the WB to be bang on for the subject matter, zoom in, or get close to fill the frame.

    As a side note, when editing your RAWs, I never adjust WB first, (even though logically speaking it's always at the top of most RAW Converters) I adjust exposure first if needed, then check the WB, you will see a difference for sure.

    Trev.
  • Thanks. It was the "what do I set the white balance setting on" to take the photo that was ambiguous. So, you are telling me to set it to CWB, and take the shot - not auto, not anything else - and then make the reference to it in the camera.

    Thanks also for the tip about getting flash in there as well, if flash will be used in the shots taken using the card.
  • TrevTrev Moderator
    Yes, read your camera's manual to see precisely what to do, depends on the make of camera.

    With Canon/Nikon they are both different on how to do it, but basically that's what you do.
  • Trev - I was shooting an event last night, and ran into a mixed-lighting situation, and didn't have my camera manual because I "thought" I knew what to do. I'm sure this would have been a piece of cake for a more experienced photographer: medium-sized room, tungsten lighting in the center, and a ring of recessed fluorescent lights around the outer part of the ceiling. I only had a couple of 1/2 CTS gels with me. I stood in the center of the room under the tungsten lights, gelled the flash, set the WB for tungsten, and took my shots. It was the best I could think of at the time. But, for situations like this, I feel will need to know as correctly as possible how to use a grey card, with and without flash.

    Dave
  • TrevTrev Moderator
    Experience over time will tell you what to do, I have not actually used a grey card for around 4-5 years for weddings, and I take a quick 'guesstimate' of the scene, decide if I need to gel with 1/2 CTS or not and go from there.

    The last time I even bothered with a grey card (well white actually, found that best for Nikons) was for family group shots in a darkish warehouse about 18 months back, lousy lighting, so I got my exposure pretty much right, and I had a large white circular reflector with me, got someone to hold it, took the shot, referenced that shot as my Custom WB and it was fine, and even then in post it was a little too 'neutral' for me so bumped up the temp by 200K to get that nicer warm feel for skin but at least I was consistent.
  • That's why I'm trying to volunteer as much as possible as a photographer right now. Experience, experience, ........ a challenge in some of these situations which I really enjoy learning from and trying to solve.
  • MichaelVMichaelV Member
    edited March 2015
    There are a number of ways to get a good white balance.  In the past, I have just shot by the hip in post-processing oftentimes taking a guess at the correct white balance.  This ultimately results in an off-color photo which some people may or may not be able to detect.  

    There are a number of gadgets, gizmos and tricks to get a proper balance.  Also keep in mind the color temperature might be different in different parts of the venue.  As the day or night goes on the color temperature may change as well from just about anything.  For example, the sun goes down changing the color temperature or someone turns down the lights.  So if you get just one color temperature at the start through the custom white balance that may not be accurate later on.  If you move through the room, there will be different color temperatures depending upon where you stand.

    Therefore, I suggest getting multiple color temperatures in different parts of the venue by taking a picture of something you know to be accurate such as the grey card.  Do this multiple times during the night while you are getting your shots.  Than later on in post production you can  be more accurate at deducting what the true color temperature might be. Ultimately, you might be guessing again, but if you have taken a picture of the grey cards throughout the events that will be a more educated guess.  I wouldnt go crazy with it taking a lot of shots of the grey card, but just a few samples during the event.

    Keep in mind, although someone might be wearing a white shirt or a tablecloth might be white, that may not be truly white or it might be in a different part of the room where the color temperature is different.      

    Out of the various devices and gizmos, the grey card is the cheapest.  If the grey card gets lost (and you will lose it) you will not be out a lot of money.  I do not see anyone using a grey card or other such gizmos during events because they basically guess during the post production and their guess might be right.  However, the proper technique is to make every attempt at getting the right color temperature during the event.  So dont be lazy, whip out the grey card and get that color temp. 
  • Thanks. I don't want to be a Photoshop/post-processing expert at this point. I'm on this forum asking what probably are pretty basic questions, but I really want to get it as right as possible in the camera because I'm not that experienced and want to be. Plus, I don't even own Photoshop/Lightroom/DXO.
  • I recall you posting a couple months ago on this topic. You should read your instruction manual because it is camera dependent. That's why you are getting different answers (per your post at the top of this thread) from people.

    User manual - See bottom of page 117 and simply follow the instructions:

    Or watch this video


  • I watched the video which still doesn't answer my one and only question - what WB setting is the camera set to when the shot of the card is taken? The kid in the video does not say what it is. Intuition tells me it HAS to make a difference. Am I wrong? Time to find the manual. I had looked in the David Busch guide to the T3i, and that doesn't tell you either, and I thought it was an expansion of the manual. Time to find my manual.

    Dave
  • You don't need to find your user manual - I put a link for you to it. It shouldn't matter what WB you use when you take the white page photo (according to the directions).
  • Oh, thanks. Sorry, I didn't see it was a link to the manual.
  • TrevTrev Moderator
    edited March 2015
    Dave,

    As Nikon Guy said you are not actually needing to set a WB when you are *taking* a Custom White Balance, (just leave it whatever it's currently on since it will be negated once you start the procedure of taking a CWB) the camera works it out, you need to follow the manual for your particular camera brand/model's method of achieving that WB.

    Here is a quick and easy method instead of taking a CWB if you wish.

    1] For each type of lighting, just place the card itself in that area, and take a shot, it does not have to fill the frame, as long as the card is evenly lit under the lighting conditions you are using.

    2] Now just take photos in that area until done, regardless of how they look on LCD

    3] Place the card again in a photo first at a new location if the light is different and take a shot, then shoot rest of photos

    4] Go home, download the images, open them up in your RAW converter like ACR/Aperture/Lightroom/Capture One whatever.

    5] Select the first image where the grey card is in, select your WB Tool/Picker, click on that grey card and the image should now revert to a very close facsimile of the lighting conditions rendering it pretty neutral, ie: Correct white balance.

    6] Select the rest of the images in that sequence and sync them with the first grey card shot, and whalla, all will change to that WB setting.

    Make sure the grey card you have is a pure/proper grey card, make sure if possible it's an 'material' type and not a painted type which will be reflective and cause hot spots thus rendering it pretty useless.

    Now, another way to then check if you are on the right path once you have done the WB, is to place your cursor over that grey card, and check the values of the RGB, they should be all roughly the same reading, and a 'perfect' grey would be 128/128/128 as in half way on the Levels scale of 256 (even though Levels goes from 0 to 255).

    If the values are say 150/150/150 or lower, does not matter, since it just means it's either a lighter or darker 'grey', as long as they read pretty roughly the same then it's neutral, ergo: A correct temperature/White Balance of that scene.

    The key here as I said, is to get hold of a proper grey card, preferably of the material/cloth kind, as they are not reflective, especially when using flash as a hard painted card can be.

    A Lastolite Ezy Balance grey card around 12 inch is ideal.

    Or go the whole hog, 3 in 1 (Black/Grey/White): HERE

    Trev.


  • Neil vNNeil vN Administrator
    Here's my take on it - listen to Trev.
  • Thanks to all for the help.

    Trev's first paragraph cleared up what was confusing me. Also, I did purchase a proper 3-card set. Also, right now I only have Canon DPP, so I will have to figure out if it can do what he has described while post processing.
  • ViccoVicco Member
    Haha, it seems to me, that at least the first five or so answerers really did not read the question. :-)
    Although it is a good one!

    I was not sure about that either, so I tried it out.
    The answer is: Yes, the WB setting of your cam then shooting the target should not matter.
    But in my experiments, then, it actually did influence the outcome a (tiny but visible) bit.

    I think, this is explainable via rounding errors or so, during the calculation process....


Sign In or Register to comment.