Thanks, I have a few other emails with new serials to add to my database, I'll try to process them this evening.
For many years when building my database I used to scan ebay regularly as it has many pictures of lenses with serial numbers, it was my main source of data. I receive maybe a handful of emails per week with new information but this is still very useful as it often includes the purchase date (lacking from most ebay listings) which gives rough guide on the age of each lens.
The old manual focus lenses are well covered. In many cases the earliest recorded serial number is within a few hundreds or tens of the known start number. Statistically the last recorded serial number should be similarly close to the actual last lens produced, so my data should be fairly complete.
The serial numbers for discontinued AF lenses are less complete or accurate. First, because the serial numbers on early AF lenses are very small and don't easily show up on ebay pictures so it was hard to get new data (in the last few years many Japanese sellers include high quality photos so I have been able to obtain more information). Second, because the AF lenses did not interest me much so I spent less time researching them
Serial numbers for lenses in current production are more difficult. For these I rely on people to email me new information, it is rare to see serial numbers for new (or near-new) lenses on auction sites. If someone emails me with the serial number of their shiny new lens then that model is, for the moment, up to date on my database. I tend to receive information from enthusiasts and professionals, so my information is skewed towards the high-end gear. Generally I receive more info about newly introduced models so my earliest recorded serial can be quite low, but interest tails off after some months or years so the highest serial can be quite out of date. There a some lenses where I didn't receive new info for a year or more.
It's even worse for the kit lenses. Even thought they are made in huge numbers, I almost never receive new serial numbers for them, the people who buy them don't visit my site. Even when I get a new serial number for an AF-S 18-55 kit zoom, they are produced so fast that my data quickly goes out of date. I don't have much interest in trawling through ebay auctions to keep these current...
And I admit, after maintaining my site for 25 years or so, my energy to keep it up to date is not what it was. I add new items as they are introduced for the sake of completeness and respond to emails when I receive them, but I rarely have the time to actively look for new serials. Maybe time to pass it on to someone else?
