|
Before WWII there was only one TV transmitter in the British Isles, in London.
"Anyway, why Great Britain didn't aligned itself to the 625 standard? To many sets arelady [sic] sold when 625 becamed the standard?"
Yes
Also, there was the logistics of the placement of the fewest possible number of very high power, very high antenna, transmitters to cover the whole country with just one channel, then two. When 625 was added it used UHF. Duo-standard receivers are a nightmare.
The 405 line standard actually generates good pictures. The low number of lines means a lower bandwidth will generate good horizontal resolution. They used a higher Kell factor on the vertical that increased vertical resolution at the expense of increased jaggies.
It took quite a while to make camera tubes really truly good enough for 625 lines. The French never came close to getting full resolution for their 819 line system.
There was also a lot of "SECAM" philosophy: "System Essentially Contrary to the American Method" even for B&W.
|