Showing posts with label auto iso. Show all posts
Showing posts with label auto iso. Show all posts

Thursday, 7 October 2010

ISO-Low or High

Traditionally ISO's have always been in full stops i.e 100,200,400,800 etc, But now we have 1/3 stops as well so now we have 100,125,160,200,250,320,400 etc, I personally always use full stops but i know others that use the 'in between' ISO's, So say that you are using ISO 400 and feel that you could use a slightly lower ISO and change to 320 thats going to help with image quality right? well not really as the 'in between' ISO's are not real ISO's, What happens is ISO 200 is a real ISO but ISO 250 is an over exposed 200 and 320 is an under exposed 400 and so on and so on, We know that over exposing is good for IQ as in exposing to the right but under exposure is bad for IQ, So in reality ISO 320 can give a grainier image that 400-Food for thought when choosing what ISO to use

Dave

Monday, 7 June 2010

Auto ISO-A new way to shoot

One of the new features on some of a todays cameras is the Auto ISO feature, You have AV where you control the depth of field and the camera sorts out the shutter speed, You have TV where you control the shutter speed and the camera sorts out the aperture, You have Manual where you control the shutter speed and the aperture and now you have Auto ISO where you control the shutter speed and aperture and the camera sorts out the ISO to balance the exposure, On the Nikon D3s you set the camera to Auto ISO in the Shooting menu, Go into the ISO sensitivity settings and set the maximum ISO that you would accept say 5000 and then set the lowest shutter speed that you are comfortable with-say 1/125  and set your aperture, After that all your images will be exposed with the same shutter speed and aperture but the ISO's will change depending on the light, So when would you use this? if you are shooting birds where there are light areas and dark areas you dont have to worry about your exposure as long as you are not concerned that you may have one image with an ISO of 200 and the next where the bird has moved into a dark area and the ISO is 2000, Great when things are changing quickly and you dont really have time to keep an eye on your shutter speed, Try it indoors and notice how the ISO changes are you move the camera around from light areas to dark, Another great feature of a great camera and another string to the wildlife photographers bow

Dave