which lense is better?
green or red?
i read something on lens burt could not understand it
somewhere it was mentioned that after July 2011 manufacturing date, all defy has better lens?
which one to buy?
At a basic level, it makes no difference. There are two camera modules for defy, the red (Bayer) and green (SOC). There are a few ways to tell which camera your mobile has, like naked eye examination etc. The best way to do it is to use an app called catlog which tells you whether you have a Bayer or a SOC module.
If you flash the leaked official 2.3 ROM on a defy with red lens, it will allow you to record 720p videos, while that with a green lens wont allow you.
I have a defy with red lens but I did not flash the official 2.3 rom because that would not allow me to downgrade to 2.2 in case I want to claim warranty. I have a rooted phone with cyanogen mod 7.1 running on it.