When teaching photography to beginners one of the hardest concepts to grasp is the relationship TV/AV/ISO and integrating the 3 into picture taking. What I try to convey is that photography is stopping the action and capturing the moment. If you do not capture that moment in focus, then you have a problem. There are other parameters such as exposure but that will be discussed at a later date. Enter ISO and pushing ISO sometimes to the max.
Say ISO and the automatic knee jerk reaction is 200 or never above 800, 100, or 1600. When I ask why, the answer is “Because of noise”. Not anymore. Firstly cameras are now achieving higher usable ISO setting, secondly, software is getting better reducing noise and lastly, noise is almost imperceptible at the sizes most people are using to show their pictures. So when faced with no chance of taking a sharp picture by keeping the ISO low or upping the ISO and knowing there may be some work afterwards, I never hesitate.
Get out and shoot. Practice and see how your camera handles ISO, so when the time comes you are comfortable with the situation.
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