Back when I first started using my DSLR camera, I had absolutely no idea what any of the settings did as I pointlessly tinkered with them every time I shot photos. It wasn’t until recently that I was given a piece of advice that really changed how I adjusted my settings: always have your ISO on 100.
In previous shoots I tried to account for poor indoor lighting by raising my ISO to extremely high levels, only to scratch my head and wonder why my photos had so much noise in them. A good rule of thumb is to start your ISO at 100 and adjust your shutter speed and aperture accordingly to compensate for the exposure.
Doing this will ensure that you have gorgeous looking photos and any noise or blur will be at a minimum. Sometimes it just isn’t possible to have your ISO at 100 due to poor lighting, but for most photos where there is adequate lighting it’s important to adjust your other settings first before resorting to higher ISO.
One benefit of newer digital cameras is the ability to produce less noise at higher ISO levels and some people recommend shooting at 200 ISO for more flexibility in camera settings without compromising the quality of the photo.
A 400 ISO level is also recommended for cloudy or dusk photos, while indoor photos should be adjusted to 1600 ISO to compensate for poor lighting. Photographers may also face the dilemma of shooting at an extremely slow shutter speed and creating a blurry photo, or shooting at a high ISO level and producing a noisy photo. A noisy photo is the better choice considering editing software allows more experienced users to remove any amount of noise, while a burred image nearly impossible to save.
While these numbers can be used a basic guideline, every shooting scenario is different and requires several elements to be taken into consideration when adjusting settings. It also depends on how new your camera is, as newer ones are more efficient at reducing noise than older cameras.