I'm stumped. Can you answer this one?

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I did a shoot at an indoor arena today which I have had WB issues with in the past so instead of my usual Auto WB I used a preset so that I would hopefully have consistency with the shots.

As you can see from the following it has been far from consistent! This is a burst of shots taken at 9fps and in LR the WB is showing the same across all five images but the results are completely different. I noticed this on the screen and took a couple of burst sequences to test it but I am puzzled as to why the results should be so different.

These are all straight from LR with no processing at all, originally shot in RAW, EXIF should be intact.

Any ideas?

WBtest.jpg


WBtest-2.jpg


WBtest-3.jpg


WBtest-4.jpg


WBtest-5.jpg
 
Fluorescent lighting changes colour quite markedly over its 50hz cycle, with short exposure times you snip out just a bit of the colour cycle and so the white balance appears off (not because the white balance in the camera is changing but because the white levels of the outside world are!)
The only way around this is to take shots slow enough to take in a complete cycle of the fluorescent lights (IE 1/50th of a second minimum shutter speed)
 
Thanks for the prompt responses and like dseered it is not something I would have considered. Unfortunately 1/50th of a second might be a no-go in this type of shoot. :lol:
 
I don't know anything really but looking at the exif, the WB is cool flourescent 3900-4500. That is quite a large gap. could the camera be taking a frame at a different temperature between the WB range?......:thinking:
 
white balance isnt going to keep the lighting the same though is it:) I got well confused doing ice hockey.. set the white balance and got same results as you with different casts. then got it explained.. went back to using AWB as there was no difference.
 
You haven't got WB bracketing on by accident?
 
Just a small correction,

Fluorescent lights typically flicker at twice the power-line frequency flickering at 100 cycles per second in the UK, and 120 cycles per second in the USA.

If the cameras shutter is open for anything less than 1/100th/s (UK), and happens to open while the tube is in the "dim" portion of its flicker cycle, it can result in vastly diffrent temperature light.
 
mho said:
Just a small correction,

Fluorescent lights typically flicker at twice the power-line frequency flickering at 100 cycles per second in the UK, and 120 cycles per second in the USA.

If the cameras shutter is open for anything less than 1/100th/s (UK), and happens to open while the tube is in the "dim" portion of its flicker cycle, it can result in vastly diffrent temperature light.
Click to expand...

was gonna say they 'flicker' twice per phase. dang:D
 
Was fluorescent the predominant/only light source?

tubes do affect colour badly, but if theres something else in the mix it can even out, a bit

N
 
Could it also be that the light source is mixed i.e. fluorescent, high pressure sodium and tungsten i.e. WB soup.

I have always had the impression that such venues and indeed lighting designers aim for a "white" light to the human eye and do not bother to consider other needs!
 
Can you fix the problem by syncing the WB temp values across to the RAW images within LR?

It may well be that although it's set to a preset value in camera ( as opposed to a hard colour temp value), as has been pointed out, that's a range of temperatures which the camera works in, and it only needs a small shift to be noticeable.
 
If there is any kind of height to the venue, and generally there is, fluorescent won't be the lighting source.
If it is a white light, the lamps are likely to be metal halide which do strobe like any discharge lamp, unless the ballast control is high frequency electronic.
Metal halide lamps do strobe all sorts of daft colours, more so than other discharge lamps, also the orientation of the lamp in the light fitting is a factor.
It is unlikely any of this would have been considered when the lighting was installed.

:)
 
I am too busy giggling at that dudes run to notice any colour changes :(
 
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