Today’s Question: I’ve noticed that when you share details of a photo, it is very common that your camera was set to 400 ISO. Is there a reason you seem to favor ISO 400 for many photos, assuming my observation is accurate?
Tim’s Quick Answer: I do use 400 ISO as my default setting, based on it offering good noise performance combined with often being a good choice based on preferred shutter speed and aperture settings.
More Detail: I recommend that photographers develop default settings that will work for them most of the time (or that are likely to be good for their next anticipated photo opportunity), and to set those as the default settings for their camera. For example, many cameras offer custom user setting options, so you can quickly establish preferred default settings.
My most common starting point for camera settings is to be in aperture priority mode (because of the way I think about exposure based on compensation) with the lens aperture set to f/8 (which is around the sharpest lens aperture for the lenses I most often use) and the ISO set to 400.
Based on the conditions I tend to shoot in and my preferences in terms of overall camera settings, I find that 400 ISO is a good default setting. My primary camera doesn’t generate much more noise at 400 ISO than I can expect at 100 ISO, so I don’t feel that I’m losing any significant image quality with this setting. Using 400 ISO also helps me achieve a little bit faster shutter speed, which is often advantageous.
Obviously, in many cases I will need to change settings. I might want to adjust the lens aperture to change the amount of depth of field in an image, for example. I often target a faster or slower shutter speed to change how motion is (or is not) rendered in the photo. And when I change either of those settings, I’ll often need to change the ISO setting as well. However, even though I often change the settings, those outlined above generally represent a great starting point for me.
Since those are my default settings, and they work well for me a good percentage of the time, it is quite likely that photos I capture will have an ISO setting of 400. In fact, after getting this question, I checked my stats in Lightroom Classic and found that with my current primary camera, 43% of my photos were captured at an ISO setting of 400. Another 34% were captured at 100 ISO, for situations where I was either trying to get a longer exposure or minimize noise.
So, clearly I am a bit of a creature of habit when it comes to camera settings (among other things). But the point is that I recommend having default settings that are most likely to meet your needs, adjusting them as needed based on the circumstances of your photography.
