Way to tell age of this Ty Cobb photo?
 

Is there a way to tell when this Ty Cobb photo was produced? The back doesn't have any stamping or ID markings that I can see. Has a couple tape repairs on the back but I don't think the old tape is covering up any id markings. It's old photo stock. It's about 12 x 22.5 or so, and it was signed by Cobb in 1949 (so I know it's not later than that) and I believe another hand has written on it that the photo was taken about 1906-7-or 1908.

I bought it because Cobb is my favorite old school player and I like the large format. I plan on framing it up for my home office, but would like to learn some more about the dating if possible.

Thanks for any assistance.

It's not from the 1908 era. But I'd have to see it in person.