Looking for tutorial to remove colour cast

swingking

I'm finding it hard to know exactly when the shot has a neutral colour cast.

Besides just messing around with the white balance slider, is there a way in PS to get an exact result.

Thanks

5uspect

In RAW? You can use the white balance tool (at the top of the camera RAW screen) to select an area of neutral grey. This should do the job nicely. If you're shooting under difficult lighting conditions take a test shot against a suitable surface to help you calibrate.
You could get an 18% grey card just for that purpose.

swingking

Is selecting an area of neural gray using WB accurate. How do you know it's an exact grey?

I like the idea of using a grey card. great tip

ThOnda

You can get quite good collapsible grey cards, as seen at the beginning of this video.

5uspect

swingking wrote: »

Is selecting an area of neural gray using WB accurate. How do you know it's an exact grey?

I like the idea of using a grey card. great tip

Accurate enough I'd guess.

swingking

Found a great tip for finding a neutral grey in your image.

1. Create a new layer and fill it with 50% grey

2. change the blend mode to difference

3. add a threshold adjustment layer which normally is used to find black points and white points of the image.

Because the 50 % grey is applied to the image with difference blending then the black point found by the threshold is actually a neutral grey!!

4. add a colour sampler point here and make sure the readings on the RGB are all neutral at this point using curves. You can also point the grey selector tool in curves towards this point and it removes the colour cast instantly!!

Hope others find this tutorial as useful as I have

oshead

I also found that on Youtube a while back. It dosn't work for all images. But it does get you in the ballpark.

paulydub

Have used this got good results from it

http://www.photoshopessentials.com/photo-editing/photo-filter/