This is an old photo of my grate grandparents taken in 1912. As you can see there is a stain over the grater part of the photo. It becomes more visible when I started to color it. I can't seem to get rid of the stain could any one help me and maybe show me what I'm missing.

Cephas, The picture you linked to is very small; check the links below in my sig to resize your picture please...

You might try scanning at the highest resolution in RGB with all modifications turned OFF

This is an old photo of my great grandparents taken in 1912. As you can see there is a stain over the grater part of the photo. It becomes more visible when I started to color it. I can't seem to get rid of the stain could any one help me and maybe show me what I'm missing.

Thanks. I reposted the thread with a larger photo.

I've merged these two threads as they're about the same subject.

First I added a 1" border all the way around the picture, straightened, cropped, then resized to original size.

Converted your picture to B/W using Russell Browns "Film-Filter" method as shown here (http://av.adobe.com/russellbrown/ColortoBW.mov) (it is a movie and may be a long download.. be patient please).
I adjusted the red and yellow channels till they both showed as white as possible using all three sliders.

Used "Neat Image" found here (http://www.neatimage.com/download.html) at the default "Muddy looking Image"to remove a little noise.

Followed this Tutorial (http://retouchpro.com/tutorials/?m=show&id=255) to clean up image.. (lots of cloning and healing toward the end)

Using this procedure should get you started on your way to wards coloring.. Get a GOOD image first before you start painting

~~Original~~cleaned a bit~~Sepia~~