I posted this in another post because someone was asking about ISO.Quote:
What ISO denotes is how sensitive the image sensor is to the
amount of light present. The higher the ISO, the more sensitive the
image sensor and therefore the possibility to take pictures in
So when taking pictures outside or with sun the ISO should be
relativity around 50-200. When in dark light situations then thats when
your ISO should be higher so more light will be going into your lens.
For my outdoor settings I set it around 100-200. So actually CRIS
1600-1800 would be too much for outdoor (well lit) settings and will
make your pics blownout. Also the higher the ISO the "grainier" the
pic will be.
ISO 100: Great for bright sunny days, at the beach or on the snow.
Produces clean images that are great for enlargements.
ISO 200: Great for overcast daylight pictures (noise levels may
increase, but in most cases not noticeably)
ISO 400: Great for lower lighting conditions (indoors, night time) or
when you need to capture faster moving subjects in lower lighting
conditions. In many consumer cameras, ISO 400 can make photos
look very noisy in dark areas of the picture. The reason a higher
speed ISO helps you capture fast moving subjects is because a
higher ISO makes the image sensor of the camera more light
sensitive. This forces the camera to use a higher shutter speed to
compensate for the extra brightness, which in turn helps to "freeze"
movement in the captured frame.
Not sure if my explanation was clear because I mixed in some of my
experiences and excerpts from a website, but I believe its about 85-90%