Old Reddish Photos

And if you want to stick with black and white, the Haze Removal tool does a pretty good job of adding some contrast.

As with most things Photoshop, there are many ways to skin this cat.

I think I would convert to black and white before making the other adjustments that have been suggested.  Once you have made the adjustments, you can also try out the Colorize Photo and Replace Sky tools.

I paid more attention to the sky and less to the skin tones on this one:

And, in future, when you are scanning, you should probably do so in greyscale mode.

First way:

- desaturate to remove color: Ctrl + Shift + U

- menu Enhance >> auto smart fix

Other way with adjustment layer applicable to other photos with the same defect:

- Create a new gradient map adjustment layer default blac to white

- adjust the black and the white slider towads the center to adjust the max tones.

You can move that adjustement layer from an open image to another open one.

There are other ways such as convert to black and white.

If you post one of the photos, we could help you better. There are several tools that can accomplish the task. But, in general, using a Levels Adjustment layer will do a good job of removing a color cast.