I want to set up a free service where photographers buying or searching for discontinued photographic equipment can reference for technical specifications. For instance, most eBay-listings of second-hand equipment are without any tech. specs whatsoever. My current plan is to do this for the mainstream, usable cameras, lenses and flash units - i.e. not collectibles.
Information about current equipment is usually available from the manufacturer's websites, and some manufacturers (e.g. Canon Camera Museum) also make information about older models available on-line. I am aware of a few non-manufacturer resources such as Botzilla for strobe trigger voltages, and Butkus for old manuals (which contains technical specifications).
By "technical specifications", I refer to things such as focal length and maximum f-stop (for lenses) and (normalized) guide number and trigger voltage (for flash units).
All the sites mentioned above as examples requires scraping to extract the data.
I am hunting for other non-manufacturer resources for technical specifications for photographic equipment to add to the planned service. I am of course most interested in quality open linked data that does not require scraping or other ad-hoc data extraction methods. However, since I suspect that few or no such resources exist, I am interested in pointers to anything useful.