It will need to be 16- or 32-bit to be of any value.
For older images, you can use a normal desktop scanner to make HDR (32-bit) scans. If the scanner software allows changes in exposure, you can scan the same image 5 times, each scan with a different exposure, and in Photoshop convert those 5 scans into an HDR image, where global constrast ranges, detail, etc., can be globally adjusted and applied. Then you can move it to 16-bit and edit at will, making it into the image you want it to be.
I find that this method yields the finest results with old photos. You can use Photoshop's tools working in the higher bit-depth to really sculpt those values.
Try duplicating the background layer (ctrl+j), then set the new layer to multiply blend mode....should help a lot. Do again if needed.
Always worth uploading the image to this forum. It's much easier to give advice when you can see what the problem is.
Here's a before and after example of old to new, using a desktop scanner to make 32-bit images out of 5 scans at different exposures. Without the additioaal bit-depth, it would have been very difficult if not impossible to do this from the faded originals using normal scans. I used Photoshop's native Merge to HDR Pro ... but more recently I'm using Google's Nik Collection : Merge to HDR Efex Pro 2, which is a really great tool for HDR in Photoshop.
Additional work was done mostly using clone for cleanup, curves adjustment layer for value adjustments, and hue-saturation adjustment layer for saturation.
And here are the 5 original scans of the most faded old shot, prior to creating the HDR image.