`How to easily correct colour cast in photos

I want to know what is the best or easiest (software) method to do a colour
correction
on a photo. The following examples happen not infrequently for me. Obviously
doing the exposure correctly is the easiest method. ;-(
EG.
#1 A picture that has been taken through a tinted window or glass. Colour
cast dependent on glass colour.
#2 Camera set to incandescent light and then used with that setting during
daylight. Extremely blue cast.
#3 Neg film that has been scanned onto disk and the result produces a Red
tint on all the images.

The software I have available is CorelDraw 7 and Paint.Net

TIA Peter.

 

Hi Peter,

There are a few ways to do this. I'm a photoshop user, but I'm
guessing your software has similar functionality. The easiest one to
try is this:
Copy your image to a new image.
On the copy, blur the image using an average (this should turn the
entire image one color).
Then level your original image using the averaged color as the grey
point.
Alternatively, you try this:
Make a duplicate layer.
Blur/average your duplicate layer, and then invert that layer (invert
all colors in the layer).
Then change the blend mode of that layer to color mode (or something
similar) and tweak the opacity as needed.

I hope that helps some!
-Jim

 

I've never used CorelDraw or Paint.Net.

Photoshop Elements has a color cast correction feature. When you
select it, you get an eye dropper tool that you use to sample a
white or gray point in the photo. It will use that point as white
and will correct the cast.

You sometimes have to sample a few areas before you get it right.

I have some shots I took through a heavily tinted green window and
the color cast corrector did a very good job of removing the green
and rendering natural looking colours.

 

A free option for you would be to download and install the GIMP. It's
a Photoshop "clone" that is really quite powerful. You can then search
the web for tutorials on "GIMP color correction" and you will find
many ways to go about it.

 

The GIMP, excellent free software mentioned by Jack W. below, also
has this feature. I have found that it doesn't always work, but
it often does and it's very easy to use.

Your Corel and paint.net software may have an equivalent.

Alan

 

Try Google's Picassa. It has colour temperature control and an eyedropper to
set neutral whites/greys in the pic.

 

Thanks for all the advice so far.
I did try GIMP briefly but found the apparent leaning curve too great and
gave up. Hence trying Paint.net
Peter Stacey.
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