What causes "grainy" pictures

[Cannons_Soccer]

and how can I fix it? My pictures just don't seem to be "sharp" once I take it off Auto ISO.

I'm using a Nikon D60 with 55-200 f/4-5.6 BK lens.

The pics are outdoor and I'm using a high ISO. The camera is new to me.

Please help.

[Canuck935]

High ISO's generally net you "grainy" pictures. Most people shoot at the lowest ISO they can for the current lighting conditions they are shooting in.

[mn shutterbug]

Underexposed photos can also show more grain.

[Dave Smith]

Cannons
How are your pics when you cut the ISO back to 200 or so?
I usually shoot at 200 with my D60 and have never had a problem with
outdoor shoots. IMHO 200-400 is more than sufficient with my rig in the daytime.

Maybe you could post a pic for us to look at.

Good luck

[mn shutterbug]

I shoot Canon, but ISO 400 and down shouldn't cause a problem with grain unless you are grossly underexposing.

[Franglais]

Can you post an example picture. And what do you mean by "high ISO"?

Usually when people talk about "grain" they mean noise. When you shoot high ISO the camera is amplifying a signal from the sensor that is weak and you get a sort of visual hiss that people think of as grain. When you look closely at the image it looks clumpy and less sharp than usual (though the drop in sharpness is usually caused by the camera's anti-noise system which tries to smooth the image out).

I used my D70 in a Church interior at 1600 ISO on Sunday. I know, it's 4 years old but I still like it and it's lighter than my other gear. I was amazed at how much noise there was - something you just don't see any more with the D200 the D300. The D60 is quite close to a D200 - you shouldn't be seeing much noise coming out of it.

[Cannons_Soccer]

My D60 has a "high" ISO setting. I'm using it for outdoor sports (last event was a track meet). I keep getting a failure error when trying to upload a picture. I'll keep trying.

[deckcadet]

ISO Hi-1 on the D60 is ISO 3200.

This should only be used in extremely low light situations when absolutely necessary. It is actually beyond the specified ISO range of the sensor since the signal is amplified so much, the signal to noise ratio is worse than required to be classified as a standard ISO speed.

Using this even in good light will cause extremely high levels of noise. You should switch back to auto ISO or set it manually to something below 800. The sensor in the D60 is clean through ISO 400 as a general rule. Noise will start to show up around 400 in very small amounts, but at ISO 800 and 1600 it will show up more and begin to affect detail. ISO Hi-1 will cause severe destruction of detail.

You may want to go to custom setting #10, which allows you to specify a maximum ISO and minimum shutter speed for Auto ISO. You can set the minimum speed to 1/250 for instance and the max ISO to 400. In P and A modes, the ISO will raise up to 400 to try and keep the shutter speed to at least 1/250s. In M or S modes, Auto ISO will raise the ISO to 400 (or whatever you set in C.F. 10) to maintain the shutter speed you set with the command dial... so if you wanted to get 1/1000 sec shutter speed outside, but ISO 100 wouldn't be enough, you could go to S or M modes, set the shutter speed to 1/1000, and auto ISO would do the rest.

[Franglais]

My D60 has a "high" ISO setting. I'm using it for outdoor sports (last event was a track meet). I keep getting a failure error when trying to upload a picture. I'll keep trying.

I don't have a D60 so I checked out the Nikon web site and the "High ISO" setting is 3200 ISO. Nikon is saying to you "Normally we recommend you use the ISO settings from 100 to 1600 but if you're absolutely desperate then we can do 3200 ISO as well. The result won't be great but it's better than nothing".

You're trying to amplify a very weak signal from the sensor and you're getting lots of noise, which the camera is trying to reduce but it's losing image detail in the process.

Don't use High ISO unless you're desperate. As someone else said, outdoors 800 ISO should be enough. Try to make sure that your shutter speed is at least 1/250s in order to freeze movement.

In order to upload onto this site you need to resize your image and reduce the number of pixels. You can't do this in the camera, you have to use software like Photoshop or ACDSee. I usually make sure my image is not bigger than 600x600 pixels.