Dear Sirs/Mdms,

1) What is the meaning of 'focus at infinity" ? How do we set a 35mm f2 lens to focus at infinity ?

2) Do you have any theory notes with schematic illustrations how the large format lense focus and calcuations of parameters like focal distance, depth of view, etc ?

3) Do you have any theory notes with schematic illustrations how the normal 35mm f2 lense focus and calcuations of parameters like focal distance, depth of view, etc ?

Appreciate if you can kindly advise me on the above issues. Hope to hear from you soon.

Sincerely,
Ho Pei Jiun