Making veins stand out

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.

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.

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.