Hello again Gents!

I am wondering if there is any databse available for dating Optar lenses by serial number? I have a 135mm Optar f4.7 on my Crown with this serial number - G16052. Can anybody tell me the date of this unit or how I might be able to find out? While I am at it, can anyone date my Crown based on it's serial number also - 905662 ...

Thanks!