Ancestry.com has a database "California, WWI Soldier Service Cards and Photos, 1917-1918" His card says there is a photo in file, but it is not with the scanned card. I have found that these photos are in another part of the database in alphabetical order. But looking at Frank Milton Brimer Card under the "Service Cards" you then click on database name and a "browse" box opens with with the name "WWI Soldier Service Cards" with an arrow. Click on arrow and the "WWI Soldiers Collection Photos" link appears. But the names Volumes only go to "BO-BON", no further. Don't know if this is an error or they are still adding scanned photos or those later Vols are missing.
The original source is from "California, World War I Soldier Service Records. Microfilm publication, 28 rolls. California State Library, California History Section. Sacramento, California". Frank's card is on Roll 03. Do not know what roll the photos are on. Maybe the library has information where to view microfilm yourself.