noise and exposure

[MACollum]

I went to the zoo today to take some pictures and I ran into a problem I have experienced a few times before. Some of the pictures were underexposed (it was so bright out I had a hard time reading the meter while looking through the viewfinder) and when I opened them in DPP and adjusted the brightness to lighten them up, there was quite a bit of noise. My ISO was set at 100. Is this what happens when dark photos are lightened so much, even when they're taken at 100 ISO? I thought that high ISO would be noisy but not low.

 

[Garbz]

The grain in digital photos especially will be most visible in the dark tones. The affect of lightening these tones will also amplify the noise. In the midrange and highlights there will be sufficient light to overcome the noise, but if you take a dark picture and bump up the brightness you get noise on almost every camera.

 

[MACollum]

Thanks for the info, I'll keep that in mind next time. I have a hard time remembering to reset the settings on the camera from a previous shoot. I took about 20 pictures with the WB set for tungsten (should have been daylight). I'll also remember to shield my eyes from sunlight before trying to meter for exposure

 

[Garbz]

The LCD is there to preview But yes I know your pain. I once changed my flash from direct to bounce of the ceiling before realising that the ceiling was orange. Needless to say my photos were ... warm

 

[Jeremy Z]

Show us some of the pix, otherwise, we are just guessing.

I suspect that a lot of your photos were backlit, which means your actual subject will be underexposed. Then, when you correct exposure for the subject, they become noisy. If you can't read the light meter, go to an auto exposure mode and use exposure compensation as necessary.

 

[MACollum]

If you can't read the light meter, go to an auto exposure mode and use exposure compensation as necessary.

I had to switch from M to P because I couldn't see what was going on with the meter. I'm not terribly comfortable with M mode yet anyway so next time I want to experiment with M I think I'll wait until I have more control over the light so I can take my time to adjust and compare. The only reason the first few pictures turned out so dark in the first place is because I forgot to check the mode before shooting (that and WB, I always forget to check them ).

I tried to post the pictures but my geocities account is screwing up.