Grey instead of white!!!

Duckydoodle

Duckydoodle

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Maureen
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I'm havin a bad light day and my white background is grey.Tried setting custom WB by taking shot of plain white card but it's not working. I'm using natural light throuh the window. What can I do to rectify this :shrug:
 
set your white balance using a grey card.

Your camera meter assumes everything is 18% reflective. So when you point it at a white piece of paper, it assumes that is too.
By pointing it at a 18% grey card corrects this.

Thats how i understand it anyway, hopefully someone will correct me if i'm wrong.
 
Either use a light meter to guage the ambient light instead of reflective-or use exposure compensation to plus 1 or 2 stops
 
Shane said:
set your white balance using a grey card.

Your camera meter assumes everything is 18% reflective. So when you point it at a white piece of paper, it assumes that is too.
By pointing it at a 18% grey card corrects this.

Thats how i understand it anyway, hopefully someone will correct me if i'm wrong.
Click to expand...

Yes almost,

The meter in camera is calibrated to 18% grey card SO when you meter on a white background the camera underexp.

Has nothing to do with WB but exposure.

Just meter on grey card or + EV 1.5 or 2.0 and and background turnes white and the auto WB hopefully will take care any colorcast. :)

Kjeld
 
I'm confused now.

The way I see it there are two different things.

WB - White balance is about the 'colour' of white - ie it is compensating for the fact that the light you are shooting under may not be 'white'. This covers the fact that sunlight/fluorescents/light bulbs are all different colours, and the wb settings compensate for the fact that you are not shooting in sunlight by adjusting the RGB balance for the light colour.

18% grey I thought was to do with exposure metering. the specific shade of grey being at such a point on the saturation between white and black that the camera can set itself so that the auto exposures will catch as much detail as possible given the light intensity.


Now I can see that there may be a connection between the colour and the intensity of the lighting conditions, but as I understood it the WB and the exposure at 18% grey are doing different things. viz, one is setting the colour adjustment and one the exposure adjustment. I therefore assumed that the 18% grey is only applicable to auto/program/aperture modes, whereas in manual mode you have control of the aperture directly. By contrast I understood that the WB applies to everything.

Please put me out of my confused state ?:help:
 
the w/b will affect the amounts of blue and red light in the final image efectively making th image warmer or cooler to compensate and thus stopping your snow from looking blue and your skin from looking like an advert for fanta under tungsten light.

If you take a shot of white paper and under expose it, it will be grey, keep on dropping the exposure and it will eventually become black.

When you're using manual mode you're just taking the computer out of the equation, if you line up the meter in the viewfinder so it's at 0EV then you're just doing what the camera would've done anyway in any auto/semi auto mode unless you had told it otherwise by using exposure compensation.

All manual effectively does is let you read the exposure off the meter and then decide on the combination of shutter/aperture to get the correct exposure instead of the cameras computer making the decision for you. E.g. in aperture priority it will choose the correct shutter speed to make the meter read 0EV forthe aperture you've chosen.

If the subject is mainly white then you know you need to make sure that the settings you use show as +1 EV onthe viewfinder meter for example.
 
Gandhi said:
If the subject is mainly white then you know you need to make sure that the settings you use show as +1 EV onthe viewfinder meter for example.
Click to expand...

So say for example if i'm taking photo's of a white car, setting the camera to +1 EV will make sure my exposure is balanced?
 
no, but it will prevent the car from looking grey in theory. +1 EV is a rather arbitrary figure I pulled out of my noggin to illustrate the point though.

Cars are a bit of an odd one anyway as they reflect quite a lot of light as opposed to say a piece of white paper or a cloth backdrop
 
Gottcha, point taken.
 
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