ISO settings
- Thread starter robp
- Start date
- Messages
- 1,288
- Name
- Darrin
- Edit My Images
- Yes
I'm no expert, far from it, but the way I understand it is that the first set of figures are native ISO settings, ie real ones, and the others are an enhanced or expanded and created via software....:shrug:
Like I say, I is only a beginner:nuts:
Like I say, I is only a beginner:nuts:
- Messages
- 1,675
- Name
- Chris
- Edit My Images
- No
Well the sensor will have a base ISO which is want it actually sees, usually 200 for nikon and 100 for canon. Anything above will be boosting the signal, less will be cutting it to get the desired sensitivity.
Boost or cut too much and it starts looking crappy, but might still be useful, hence the extended ranges. The "normal" range is just what the manufacturer is a useable range for most people.
Boost or cut too much and it starts looking crappy, but might still be useful, hence the extended ranges. The "normal" range is just what the manufacturer is a useable range for most people.
Canon Bob
Loves the Enemy
- Messages
- 9,754
- Name
- Bob
- Edit My Images
- Yes
My understanding is that the quoted Iso range (at normal Iso stops) is based on the analogue gain applied to the sensor....pure Iso if you wish.
The top end expansion is performed at the analogue gain 1 stop lower but then the whole RAW data capture is digitally shift up by 1 EV. At the bottom end, a similar situation but shifted down by 1 EV.
The end result is the dynamic range will be clipped by 1 stop at whichever end you're playing with......this clipping will be over and above any clipping that occurs at capture.
Bob
The top end expansion is performed at the analogue gain 1 stop lower but then the whole RAW data capture is digitally shift up by 1 EV. At the bottom end, a similar situation but shifted down by 1 EV.
The end result is the dynamic range will be clipped by 1 stop at whichever end you're playing with......this clipping will be over and above any clipping that occurs at capture.
Bob
- Messages
- 4,422
- Name
- Robert
- Edit My Images
- Yes
Base iso has been 100 for half a decade!
You probably have the last model to be base 200.
Last edited:
KIPAX
Seriously Likeable
- Messages
- 20,980
- Name
- KIPAX Lancashire UK
- Edit My Images
- No
Thats the way I have always known it as well.. But never felt the need to question it so I cant say its fact... but it's what I was always told
- Messages
- 3,007
- Name
- Umm......................
- Edit My Images
- Yes
Base iso has been 100 for half a decade!
Nikon's D700 was launched on 1st July 2008 with a base iso of 200, the same as the D300, and also the D300s which was launched in 2009, so hardly "half a decade"!
Also note that 200 is not the base iso (which is closer to 160, ref Mansurovs), but the lowest standard iso setting before using what are referred to as extended settings.
HTH.
Base iso has been 100 for half a decade!
A number of the Sony DSLR/DSLT also have a base ISO of 200 - and since Sony produce the sensors fro a number of Nikon's, I'm hardly surprised Nikon's have the same.