I wanted to write up a little article to help those of you who want to get more comfortable with shooting in low light or very little light and maybe even inspire some of you to get out there to shoot after sunset. Hopefully, this helps you understand when to change your settings in order to get your desired outcome.

Let's get started! 

I often underexpose my portraits when I am working during sunset because it helps me keep more of the detail. I usually just underexpose by a stop or two. You'll notice that in the first before and after that I have my settings at; 1/125 sec f1.4 and ISO 320 

The second photo, I used the Modern Market presets (You can get these results by using in the Hybrid Film Preset Collection which will give you beautiful bright and airy edits.)

EDITED WITH: The Hybrid Film Preset Collection by Modern Market. 

THE LIGHT
The sun was not fully set (you can see where it was behind my subject blocked by clouds) and gave me enough light to work with. 

SHUTTER SPEED
I kept my shutter speed at 1/125 sec. Fast enough which I allowed me to easily shoot while holding my camera and not get any camera blur. Since my subject was moving very slowly (swaying back and forth in one spot with her little one) 1/125 worked fine. Typically, I try to keep my shutter faster than 1/160 sec when working with clients that are regularly moving around.

BUT when given the choice, I will slow my shutter down a little in order to keep my ISO low. 

Anything lower than 1/125 would put my image at risk for blur. If you are noticing that your subjects seem a little blurry, it's probably due to your shutter speed being too slow.

APERTURE 
In order to let as much light as possible in, I shot wide open at 1.4. This gives me a shallow depth of field and allows as much light as possible to come through my lens. (remember, the higher the number is...the smaller the aperture hole will become...)

ISO 
You'll notice that my ISO is set to 320. I try my best to keep my ISO as low as possible and would rather work with a slower shutter speed when working with less light. ISO is one of those things that can quickly add a lot of unwanted noise to images and it's usually what people are most confused about when it comes to my before and after. Most people would raise their ISO in the dark, in order to make their camera more sensitive to light, but I've found that keeping my ISO as low as possible (under 400) gives me nice and clear images as long as I have a little bit of light to work with.

SHOOTING IN THE DARK

Working in LOW light is completely different than working in (almost) NO light. And I stayed extra late at my last session to get a few shots to show you what my settings would look like and how with the right tools, you can even create some really beautiful portraits. 

THE LIGHT
This was shot about 20 min after sunset. You can see in the first image that there's still a little bit of after light in the sky, but really...it was dark enough where I could not see very much. Shooting an image THIS dark makes it really difficult to recover in post-processing. 

SHUTTER SPEED
Now here is the key element in what I changed in the top and bottom photos. On the top images, you'll see that my shutter speed was set to 1/125 just the images above. On the left is the unedited version, and on the right is the edited version. Since there was so little light, a lot of details were lost, so when I raised the exposure in Lightroom, I ended up with a ton of grain and a whole lot of funky colors (look at those greens) Recovering images like these is difficult. So although I enjoy underexposing a little, I avoid underexposing too much. 

However, notice what I changed on the bottom images. Instead of raising my ISO (which would bring A LOT of grain and noise) I slowed my shutter speed way down. Now keep in mind, I did not shoot these with a tripod, and simply stood there holding my breath as the shutter clicked. 

For fun: go change your shutter speed to 0.3 sec and see for yourself how hard it is to stand still and how long it feels compared to 1/125 sec.

BUT the key to all this is that it gave my camera enough time to let MORE light in, all while keeping my ISO low. In the past, I have done 6+ second long exposures with nothing but the moonlight in the past (using a tripod) and it looked like it was taken in the daytime.

APERTURE 
Again, in order to let as much light as possible in, I shot wide open at 1.4. This gives me a shallow depth of field and allows as much light as possible to come through my lens. (remember, the higher the number is...the smaller the aperture hole will become...)

ISO 
And just like the others, keeping my ISO as low as possible.

RECAP:

1. Shoot wide open for portraits, to allow as much light as possible to come in. If you're doing this for landscape shots, raise your aperture to get more in focus.

2. Keep your ISO as low as possible, ensuring you avoid unwanted grain. 

3. Slow your shutter down. If you drop below 1/125 you'll need to hold very still or use a tripod. 

Extra tip; If you are shooting in the dark and your camera can't even see what you want to focus on, bring a flashlight to shine on your subject, switch to manual focus, make sure everything is focused correctly, then turn the flashlight off and take the shot :)

And if you didn't bring a tripod, try finding a nearby rock, ledge, camera bag or stabilize your camera by sitting and resting it on your knees. If you are working with very long exposures, using a trigger helps as well. 

Most importantly; Remember that even shooting in the dark can be a ton of fun. You'll just need to play around with your exposure time to allow enough light to brighten up your portrait. 

Special thanks to my dad, who has taught me everything I know about shooting in low light and showed me that even when we see nothing if we wait long enough we can light up our world using nothing but starlight. 
Here's one of his images.