Posted By:
davidcyclebackYour above photo appears like an official news photo and not some basement made creation. It may have been made a few years after the image was shot (this was done by legitimate news services and photographers, including folks like George Burke) but none the less appears to be a legitimate news photo.
As far as your other photo goes, I haven't seen it and don't know the year of the subject. If it's an 1880s subject it will be much easier to identify problems as 1880s are subantially different than many 1920s photos. In particular, an 1880s baseball photo will almost always be mounted (the paper photo pasted to a cardboard sheet or similar 'mount').
For collecting old sports photos, many collectors will have a list of stamps to look for. Some photo services and photographers were around for a small period of time. For example, ACME Newspictures changed its name in the 1950s. This means that, while the ACME stamp doesn't pinpoint a year, it shows that that Red Grange photo is at least old. George Grantham Bain died in 1941 so his stamp on a photo not only proves it was by the ever popular photographer but the photo is old. Some big aucton houses like MastroNet and REA will picture or mention the stamp on the back in auction. Along with having a feel for what old photos look like and dealing with kowledgeable sellers, this is is the type of stuff many photo collectors look for.
A stamp from a well known company or photographer also shows that the photo is 'official'-- meaning the photo was made by someone or some organization who had the legal/contractural rights to make the photo. An MGM stamp on the back may not pinpoint the year of that W.C. Fields photo, but does show that it was officially made by or for MGM. Many photo collectors are only interested in official photographs, just as many modern baseball collectors pass on Broders and unauthorized reprint issues. And notice I referred to the above Mathewson as appearing to be an 'official news photo.'