How to Turn Day to Night Using Photoshop for Urban Landscapes

Have you ever wished you’d photographed something at night? You may not have had the time, knowledge, or gear to do it, but you still regret not getting that shot.

In some cases you may be able to return at night and have another go. But if you can’t, you can quickly turn day to night with Photoshop.

In this article I’ll show you how you to turn your daytime urban scene into a nighttime one using layers and masks. I’ll also give you a few tips on the details you should take care of for a more realistic effect.

But first I want to explain the idea behind this technique so you can apply it to all kinds of photography.

The blue night and the yellow light

You may have noticed that different lights have different colors. Sunsets are redder and warmer than the sunlight at noon. The table lamp from your bedroom is more yellow than the fluorescent light of an office building. And so on.

This is called the color temperature, and is measured in Kelvin degrees. (You can see it in full in this color temperature scale.) And you can take advantage of it to simulate night time by colorizing your image accordingly.

Make it night

First, you need to change the white daylight into a dark blue that corresponds to the night light by adding a blue layer. You can do this in various ways, although I find the easiest way it to select Layer -> New Adjustment Layer -> Color Lookup… from the menu and clicking OK.

From the Properties panel, open the top drop-down menu and choose any option that gives you a blue tone such as Moonlight, Foggy night, or Night from Day.

If you’re more experienced, and want to to have full control, you can work with a RAW file. At the top of the adjustment panel of the ACR window is a slider where you can adjust the color temperature. You can also enter the Kelvin degrees value you want directly according to the scale I mentioned before.

Turn the lights up

Next, create another layer that’s yellow or amber. If you’re using Adjustment Layers, remember to duplicate of the original first and then add the color one on top of it. If you’re sticking with the Color Lookup adjustment layer style choose Edgy Amber or Candlelight. Once you have it, merge the adjustment layer with the copy you created from the original.

If you’re doing it from ACR, don’t just duplicate your layer. Use the Create a New Smart Object via Copy option instead, or the first layer will go yellow too. You can find this option by right-clicking the layer and choosing it from the menu. Then double-click on the thumbnail to open ACR again and drag the slider to the yellow side.

You now need to add a mask to this yellow layer. You can do this by clicking on the Layer mask button on the bottom of the panel. Once you’ve created it, click Invert in the properties panel. We do it this way because the white mask will show all the content and the black one will block all of it. (To learn more about it, check out Getting Started with Layer Masks in Photoshop – a Beginners Tutorial.) For now you’ll want it all covered so you can paint only what you need to in the next step.

The yellow corresponds to the tungsten light from light bulbs, which you can use to paint lamp posts, windows and any other source of light that might be available during night time. Identify these sources and, using the Brush tool, start painting in the Layer Mask with the brush set to white.

For windows, I find it easier to paint the entire rectangle and then paint out the divisions with the black brush.

This also works for any corrections or detailed work. If you paint something by accident, change the color of the brush to black and paint back over it to cover it again. This is why we’re using masks. The work is non-destructive, and you can easily go back and forth.

The Giveaways

It’s up to you how much work you want to put into the transformation. But keep in mind that the more details you do, the more realistic the effect looks.

For example, the lamp will shed some light onto the wall where it’s hanging, so you’ll want to illuminate that part as well. With the same Brush tool you were using, diminish the opacity from the Options Bar and paint the wall where the light would be hitting. Keep diminishing the opacity as you get further away from the light source.

Another big giveaway is reflective surfaces because light would reflect onto them. In this example, the water in the canals needs to have reflected light. But it may also be needed for cars or puddles, so keep an eye on your scene and paint those as well.

There you have it: from day to night using nothing more than  layers and masks.

I hope you enjoyed this technique. I recommend you go out and do some night photography so you can learn how light, tones and colors behave. The more you understand it, the better you will be able to replicate it in post-production.

If you need some help getting started, check out The Ultimate Guide to Night Photography.

And to get some inspiration for your next digitally created night scenes, here are two great articles:

• Creating Moods with the Kelvin Scale
• After Dark – 22 Night Photography Images.