# [Wet Thumb Forum]-White Balance - Manual Setup



## Guest (Aug 6, 2003)

*WHITE BALANCE*

White balance is a name given to a system of colour correction to deal with differing lighting conditions. Normally our eyes compensate for different lighting conditions, but when taking a still with a digital camera the camera has to find the "white point" (the assumption that a white object must appear white) to correct other colours cast by the same light.

Most digital cameras feature automatic white balance, this means that the camera looks at the overall colour of the image and calculates the best-fit white balance, however these systems are often fooled (especially if taking a photograph dominated by one colour, say green). Most digicams also allow you to override the automatic white balance by choosing a white balance manually, typically sunlight, cloudy, fluorescent, incandescent etc.

Modern "prosumer" digital cameras also allow "white preset" which simply means measuring the white point from a white sheet of paper or card (or nearby wall), the camera will then record that temperature and use it to correct all images until you reset it.

*Colour Temperature*

Each type of light can also be represented by a numerical colour temperature, here are the (rough) colour temperatures of typical lighting conditions:

Type of light Colour temperature 
Incandescent 2500K - 3500K 
Twilight 4000K 
Fluorescent 4000K - 4800K 
Sunlight 4800K - 5400K 
Cloudy daylight 5400K - 6200K 
Shade 6200K - 7800K

*What are your techniques when using White Balance settings ?*

[*]Do you use white material placed in outside or inside the tank ?
[*]What material as white source ?
[*]How do you position white material in relation to tank light ?
A) Exactly perpendicular 
B) At the angle ?
C) No difference


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## Guest (Aug 6, 2003)

*WHITE BALANCE*

White balance is a name given to a system of colour correction to deal with differing lighting conditions. Normally our eyes compensate for different lighting conditions, but when taking a still with a digital camera the camera has to find the "white point" (the assumption that a white object must appear white) to correct other colours cast by the same light.

Most digital cameras feature automatic white balance, this means that the camera looks at the overall colour of the image and calculates the best-fit white balance, however these systems are often fooled (especially if taking a photograph dominated by one colour, say green). Most digicams also allow you to override the automatic white balance by choosing a white balance manually, typically sunlight, cloudy, fluorescent, incandescent etc.

Modern "prosumer" digital cameras also allow "white preset" which simply means measuring the white point from a white sheet of paper or card (or nearby wall), the camera will then record that temperature and use it to correct all images until you reset it.

*Colour Temperature*

Each type of light can also be represented by a numerical colour temperature, here are the (rough) colour temperatures of typical lighting conditions:

Type of light Colour temperature 
Incandescent 2500K - 3500K 
Twilight 4000K 
Fluorescent 4000K - 4800K 
Sunlight 4800K - 5400K 
Cloudy daylight 5400K - 6200K 
Shade 6200K - 7800K

*What are your techniques when using White Balance settings ?*

[*]Do you use white material placed in outside or inside the tank ?
[*]What material as white source ?
[*]How do you position white material in relation to tank light ?
A) Exactly perpendicular 
B) At the angle ?
C) No difference


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## ekim (Jan 31, 2004)

Great post Jay!

Did you ever get around to trying the manual white balance?



> quote:
> 
> Do you use white material placed in outside or inside the tank ?


Yes, it has to be inside the tank! There is no point in doing it under room lighting if the tank lighting is a different temperature (witch it is almost always).



> quote:
> 
> What material as white source ?


I use a white dish or ice-cream container lid.



> quote:
> 
> How do you position white material in relation to tank light ?


I place it in the middle of the tank depth wise and also hight wise!

*My Digital Gallery*


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## Guest (Aug 6, 2003)

> quote:
> 
> Originally posted by ekim:
> Did you ever get around to trying the manual white balance?


I did. Pictures came out a lot better but few a bit overexposed. Still working on the layout though.



> quote:
> 
> How do you position white material in relation to tank light ?
> 
> --I place it in the middle of the tank depth wise and also hight wise!--


I think this is very important point in setting up white balance.

[*]If Material is place at angle which will *reflect* tank light, you will get over-exposed pictures
[*]If Material is placed at opposite angle which will *"look into substrate"*, you will get under-exposed pictures
[*]If Material is placed *perfectly perpendicular* to tank light you should get correct output.


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## ekim (Jan 31, 2004)

Sorry, I didn't understand the last question right!
Yes, as perpendicular as I can set it!

*My Digital Gallery*


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## MarcinB (Apr 16, 2004)

Jay, why setting the white balance manually can result in under- or overexposed pictures? Isn't it only for adjusting the coloros? Does it fool the light metering system of the camera?

150L (40G) planted tank
click here for photo


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## Guest (Aug 6, 2003)

> quote:
> 
> Originally posted by MarcinB:
> Jay, why setting the white balance manually can result in under- or overexposed pictures? Isn't it only for adjusting the coloros? Does it fool the light metering system of the camera?


Marcin,

I'm not 100% sure on this.

This was my personal experience but I have to play around a little bit more with manual WB and its setting.


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