Computer Graphics with Photoshop - Making veins stand out

Author

Making veins stand out

Phil M

2005-05-10, 7:15 pm

Taking some pictures of a very white skinned friend we were surprised
how the blue of her veins stood out. She's shown them to a friend who
says that she'd like to use them in a human biology project. (legs and
arms only, I'm assured).

I've been asked to see if I can make the veins more apparent but the
only way that I can find to do this (other than manual darkening) is
to darken the mid range of the picture which makes her skin go orange
(and even more like a horror film).

The veins, to my surprise, aren't really blue but seem to just be a
darker shade of 'skin'. I've tried selecting colour range but as there
isn't much of a colour difference this doesn't really help.

Has anyone any suggestions as to how I can achieve this rather odd
request ?

I'm using Photoshop 7.

Mike Russell

2005-05-26, 7:14 pm

Phil M wrote:
> Taking some pictures of a very white skinned friend we were surprised
> how the blue of her veins stood out. She's shown them to a friend who
> says that she'd like to use them in a human biology project. (legs and
> arms only, I'm assured).
>
> I've been asked to see if I can make the veins more apparent but the
> only way that I can find to do this (other than manual darkening) is
> to darken the mid range of the picture which makes her skin go orange
> (and even more like a horror film).
>
> The veins, to my surprise, aren't really blue but seem to just be a
> darker shade of 'skin'. I've tried selecting colour range but as there
> isn't much of a colour difference this doesn't really help.
>
> Has anyone any suggestions as to how I can achieve this rather odd
> request ?
>
> I'm using Photoshop 7.

The veins are skin color with cyan added, which has the effect of darkening
the overall tone and saturation of the skin color, which is a reddish
orange.

Here are some tricks to try. Use Image>Selective color to dd cyan to blue.
Dup the blue or red channel to a new layer, and use the blue channel in
darken mode, or the red channel in lighten mode. Or use the b channel of
Lab as a mask and use curves or levels to darken the veins, lighten the
skin, or both.
--

Mike Russell
www.curvemeister.com