- #1
edmondng
- 159
- 0
why does the spot size increase with lower f#.
Lets says you have 2 lens of the same material, and diameter, just different focal length. F/2 has higher spot size than F/3 but F/2 is faster. Is spot size a characteristic of a lens? So if your detector is fixed in size you need to get a lens that fits about the size of your detector or less otherwise it will result in blurry image?
Lets says you have 2 lens of the same material, and diameter, just different focal length. F/2 has higher spot size than F/3 but F/2 is faster. Is spot size a characteristic of a lens? So if your detector is fixed in size you need to get a lens that fits about the size of your detector or less otherwise it will result in blurry image?