Today I'm going to share with you what I feel is the most important rule that a photographer must know when it comes to modifying and controlling the quality of light.

Understanding lighting is a combination of rules of science and implementation of artistic influences, and can vary from person to person, however there are some hard and fast rules that I like to stick by.

Ok here it is...

The LARGER the light source is relative to the subject the SOFTER the light, and conversely...the SMALLER the light source is relative to the subject the HARDER the light.

There, that's it. One of the most important rules of lighting broken down into a simple, easy to remember sentence.

If you want softer light there are two things you can do..

Bring your light closer to the subject
Switch to a larger modifier
or both!

For a harder light source:

Move the light further from the subject
Switch to a smaller modifer

One way to look at this is by using the sun as an example. While the sun is arguably a huge light source, because it's so far away it's relatively small in the sky, thus creating a 'harder' light source.

Pop open a diffuser while in the sun and those beautiful rays soften and become larger relative to the subject o give you a more flattering light.

So what are the real differences between hard and soft?

When you look at images lit with soft light you see a subtle gradient from shadow to highlight, when you switch over to a hard light that transition is abrupt creating a very crisp shadow edge.

Knowing these differences you can basically apply this rule whether you're outdoors in natural light or in the studio.

Let's say you have a single light in the studio a 3 foot Octabox for sample and you want to create a softer light source ... what can you do?

Simple! Move the light source closer to the subject thus making it softer.

Let's say for some reason you don't want to or can't move the light source because of space constraints, you can switch over to a larger light source such as a 5ft Octabox.

The opposite of this rule is also true when it comes to hard light. You can use a smaller modifier, or none at all with just a bare head, or you can back the light up as far as possible (remember the sun rule! ☀). Even switching to a speedlight would make even harder light.

So what do you think? Seems like an important rule right?

The more you work with light the more you'll understand how changing distance or switching modifiers affects the outcome of the quality of light. It may be a simple rule but does require some practice to master!


If you're totally new to studio lighting or have some experience but feel like you haven't yet mastered it (or perhaps just need a refresher) check out my ultra indepth class Master Studio Lighting: https://lindsayadler.photo/masterstud....

Gear mentioned in this video:

✅ Profoto 3ft Octabox: https://adorama.rfvk.net/dvRQj



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