AF working range/detection range?
Carl Snyder wrote:
What determines a camera's ability to focus in low light? I
noticed that the 20D has a rating of -0.5 to 18, while the 1DII is
rated at 0 to 18. The detection range of the nikon cameras is -1
to 19. What do these numbers mean and what determines them?
These are EV numbers and they are a convienent way to indicate absolute light levels without going into ISO, apertures and shutter speeds.
EV 0 to -1 are "subjects lit by dim ambient artificial light", according to Fred Parker's EV chart: http://www.fredparker.com/ultexp1.htm .
There is a good explanation ov EV in the dpreview glossary, under "Exposure": http://www.dpreview.com/learn/?/Glossary/Exposure/Exposure_01.htm
There is a somewhat simpler intro to EV at my IR resource page:
- Fujifilm X-T223.6%
- Nikon D50025.4%
- Nikon AF-S 105mm F1.4E8.2%
- Olympus M.Zuiko 12-100mm F47.5%
- Panasonic Lumix DMC-G857.2%
- Sigma 85mm F1.4 Art6.7%
- Sigma 50-100mm F1.8 Art5.1%
- Sony a63006.4%
- Sony Cyber-shot RX10 III3.7%
- Sony Cyber-shot RX100 V6.3%
|Race by mdbinasif|
from Your City - Kids Play
|Altaussee Austria by IFRPilot|
|Sunrise at Mono Lake by ed rader|
from My Best Photo of the Week