Obviously, we want to use the lowest ISO setting possible on our camera. During the daytime, this typically means staying somewhere in the 100-400 range. Sometimes, conditions arise that require something much higher.
I found myself in this situation recently when we came across this herd of wild pigmy elephants along the bank of the Kinabatangan River. It was late in the afternoon, with an extremely overcast sky. We could hear lightening in the distance! In addition, we were in a boat on a river where there were many other boats. Some of these boats were also watching the elephants, but others were barges and fishermen causing quite a bit of movement in our little boat.
Based on the fact that I was moving, the subject was moving, and the light was low, I needed to make some adjustments. I knew that I needed to be at 1/1000 of a second for my shutter speed. Also, since the boat was rocking, I needed to allow for some additional depth of field. I opted for an aperture of f/8 for most of my shots. In some cases, I dropped as low as f/6.3.
If I remained at ISO 400, my photos would have been too dark. I needed to increase my ISO. Today's current generation of cameras have pretty amazing ISO performance, but I wasn't sure if I could get decent results if I went too high. Nevertheless, my meter was showing me that in order to expose the elephants properly, in most cases I needed to set my ISO to 8000.
I will admit, I was not sure if I would get any usable photos. I did know that my only chance was to rely on my camera's capabilities, and hope that I could make the appropriate adjustments during post processing.
When I opened the images in Lightroom, there was some noise. Fortunately, there was not enough noise to ruin the image. I did two things to reduce the noise:
Set Noise Reduction sliders in Lightroom, to 35 for Luminance, and 60 for Detail.
Reduced the image size to roughly 18 Megapixels.
This gave me images that are large enough to print , and sharp. They also had an acceptable level of noise.
Obviously, it would have been nice to shoot at an ISO level where I didn't have to worry about noise. When conditions don't allow for lower ISO settings, it is nice to know that there are options.
Here are some other photos taken that afternoon. I have included the camera settings in the image description. (Hover on the image to see the settings)