ISO
ISO is how basically how sensitve the sensor is to the light hitting it.
The bigger the number the more sensitive or brighter the pic will be, however this increases 'noise' - which appears as a 'grain' on your shot
ISO 100 200 400 800 effectively a 1-stop jump on each number and gets progressively sensitive but more noisey.
Shutter Value
1/250 is a shutter speed, how long the shutter is open in whole or fractions of a second.
each value here is a one stop jump, progessively opening longer/brighter.
1/1000- 1/500- 1/250- 1/125- 1/60- 1/30- 1/15- 1/8- 1/4- 1/2 - 1second
Aperture Value
Is the width of the aperture in the lens, relative to the focal length, in 1stop increments
1.0 1.4 2 2.8 4 5.6 8 11 16 22 32
The simpliest way I look at aperture is as a fraction ie.
f2, replace the 'f' with a 1 = 1/2
f4 = 1/4
f8 = 1/8
You can see that 1/2 is bigger than 1/4 - bigger is wider, therefore f2 is a brighter aperture. This also effects Depth of Field but thats another story
I'm only a beginner too, so whilst there will be better technical explainations, these get me by lol :bonk:
Andy
ps...i should point out that although f2 to f4 looks like a halving or doubling in arthmetic, it not a havling or doubling of light. I read on here that you multply or divide the fnumber by 1.41 to get to the correct 'stop' - or doubling halving of light