Racehorse Photograph, Over 100 years old

I found this framed photograph in a barn in Bonanza Oregon in the mid 1990's. The frame and glass were both intact and in good condition. I had it remounted with acid free mats and backing but kept the original frame and glass, It measures approx 30x24 framed.

The horses name, Altamax is on the photograph, as well as the photographers name and address. Hodson Geary St. Sf.

The photograph has been hand colored with what I believe to be pastels. 

Altamax was born in 1894. Here is his allbreed registry, 

http://www.allbreedpedigree.com/altamax

I learned quite a bit about him from the book The American Thoroughbred by Thomas B Merry. Here is the link the book.

 https://books.google.com/books?id=2Z5AAQAAMAAJ&pg=PA170&lpg=PA170&dq=altamax+thoroubred&source=bl&ots=CgWPP-4yd2&sig=euf5jgKImFax1zhRXTbfjyXW1Yc&hl=en&sa=X&ved=0ahUKEwiBrtqU7NnLAhVV6mMKHc63AHUQ6AEIIzAB#v=onepage&q=altamax%20thoroubred&f=false

There is a photograph of him in the book and the white rear sock matches the photograph I have. 

Hodson the photographer lived in San Francisco and Sacramento during his career. Here are two links to the information I found on Mr. Hodson

https://books.google.com/books?id=FRU1AQAAMAAJ&pg=PA768&lpg=PA768&dq=hodson+photography+sacramento&source=bl&ots=mIHL7s1Ah3&sig=V5c8W7yw6fq6XU-dUVM4VVE6GfA&hl=en&sa=X&ved=0ahUKEwiFtKvg7NnLAhUTzmMKHVM-CkAQ6AEITjAJ#v=onepage&q=hodson%20photography%20sacramento&f=false

http://www.shadesofthedeparted.com/2008/04/this-weeks-photo-14-april.html

I am curious what this is worth and if there is a market for this type of racehorse memorabilia. 

Thank you very much for your time and consideration