What do we mean by 'poor light'? I guess most people, even some photographers, would take that to mean low levels of illumination. At best misguided, at worst woefully inaccurate.
Light is the lifeblood of photography, as without light there would be no photography. Check out the Greek origin of the term if you need to.
Many years ago (the late 1980s to be more specific) a fellow photographer (a retired guy called Fred, I forget his surname) related his experience in using a new print film, Kodak Ektar 25. Yes, that's the ISO speed, something hardly conceivable these days. He took an image of a lake on a dull overcast afternoon which looked very good printed large, despite he said 'what you might consider poor light'. But the image engaged the viewer. So if the image can do that it was hardly 'poor light'.
f/2.8, 1/60, ISO 3200
Why would I, and many other photographers say cloudy conditions are 'good light'? It does depend on what you're trying to capture of course. If you're after fast action then dull conditions will be a challenge, but much less so these days with very good high ISO performance. That soft and even light will avoid contrast problems whatever subject you're taking. For macro work of delicate details and flowers it's ideal, and portraits will have an attractive quality with no hotspots. Landscapes can look uninspiring under flat light so you'll need to think more about shape and line as you would for monochrome images, and while you won't get the warmth of a sunset for example, it's a different style of image you'll capture. That said, light just after dawn and before sunset is low in intensity but isn't often described as 'poor' (and nor should it) possibly because it's soft and warm.
f/2.8, 1/160, ISO 6400
If we erroneously regard 'poor light' as 'low in intensity' then let's consider some occasions where that's the case such as indoor events, night-time sports, music performances, urban scenes at dawn and dusk, and so forth. All those have lighting with lots of opportunities to capture moody, atmospheric or dramatic images. Low light levels make it easier to capture the red hot glow from carbon fibre brake discs on Formula One cars.
Look at what the light is doing, how it interacts with the elements in a scene. Some of those scenarios will be tricky to expose for, perhaps another reason for people thinking the light is 'poor'. Conversely I'd say that is rich light, rich in terms of creative possibilities and great results. Observation, creativity and technique may need to step up a gear or two but putting the camera away isn't, or shouldn't, be your default action.
f/8, 1/200, ISO 400
If you want to use the term 'poor light' reserve it for such occasions as the middle of June under a cloudless blue sky because that is harsh uncompromising light that won't show off a subject to it's best. Let's, for the technically minded in a hypothetical world, say that a sensor can handle such contrasty light. That won't make the result any more acceptable. The light doesn't mould the subject into looking attractive. There's little shape or modelling and certainly little to stir the imagination or excitement of the viewer. We should avoid the use of the word 'poor'. Inappropriate, or not ideal would be more apt descriptions. For portraits such harsh bright light is very unsuitable. Ugly shadows with people squinting against the sun produces unflattering results. It is handy for contra-jour photos especially with the use of a reflector or fill in flash.
A single harsh light can, when used in the right way, produce some good results – I'm thinking Film Noir where a lot of thought is put into lighting position and quality to get a desired effect.
So don't ever use 'poor light' to mean 'low light'.
f/9, 1/160, ISO 400
All text and images © Keith Rowley 2021