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View Full Version : Iso Settings On A Nikon D50



sofishan
07-13-2007, 10:07 PM
Hi Everyone

Do I Have To Play With Iso Setttings When I Change To Manual Mode And How Does This Work?

erichlund
07-13-2007, 11:15 PM
Switching to manual mode means that you adjust both aperture and shutterspeed directly. While ISO setting will affect what aperture and shutter speed you use, manual mode does not automatically mean you will need to make some adjustment to ISO setting.

ISO is the sensors sensitivity to light. Most dSLRs have a lowest ISO from 50 to 200. This is the cameras least sensitive ISO setting, meaning it will take the greatest amount of exposure to get a certain amount of "light impact" on the sensor. By raising the ISO, you increase the sensitivity. If I raise the ISO from 100 to 200, I am doubling the sensitivity of the sensor, or raising the sensitivity by one stop, to put it in more "photographic" terms. So, if at ISO 100, I had an exposure of 1/30 second at f8, at ISO 200, my same exposure for the same light conditions would be 1/60 second at f8 or 1/30 second at f5.6. (If you are wondering why not f4, then you need to read about exposure and f stops. f numbers are wierd until you understand the math that causes them to be what they are. A quick google on f-stop yields this wikipedia reference (http://en.wikipedia.org/wiki/F-stop). It's not the be all and end all f-stop info, and there are probably some errors in there, but it's a quick starting point.

How you set ISO is camera dependant. On my D200, I press a button specifically for ISO, and rotate a dial. Some cameras require you to go into menus. Some have a button that is sometimes for ISO and sometimes for other things, depending on the mode of the camera.

rawpaw18
07-14-2007, 04:21 AM
Nice info Eric,

Your D50 also has an auto ISO feature, this will allow your camera to choose
which ISO to use. There are more ISO settings available to you with it set to auto, if you check your exif you will see odd numbers like 640, 320 things like that. The D50 will only use as much ISO as needed, which helps keep the noise levels down.

K1W1
07-14-2007, 06:47 PM
Nice info Eric,

Agreed, great explanation.


Your D50 also has an auto ISO feature, this will allow your camera to choose
which ISO to use. There are more ISO settings available to you with it set to auto, if you check your exif you will see odd numbers like 640, 320 things like that. The D50 will only use as much ISO as needed, which helps keep the noise levels down.

I tried Auto ISO a couple of times on my D50 but stopped because I found that it tended to go straight to the top and virtually all photos were ISO 1340 or ISO1600 or thereabouts when IMO I was getting better less noisy images in the same light with ISO800. I think that the Auto ISO is something that you really need to play with so that you understand what the camera is likely to do in any given circumstance rather than being disappointed later on when you look at the photos on a PC.