Lightroom previews are an essential part of the editing workflow. But with so many different preview types, it’s easy to get confused. For example, do you know the difference between Minimal, Standard, and 1:1 previews? Do you know what a Smart Preview does, or why 1:1 previews are useless in the Develop module?
In this article, I’ll share everything you need to know about previews, including:
- Why Lightroom uses previews (and why Photoshop doesn’t)
- The 6 preview types and what they can do for your image editing
- How to easily build previews in Lightroom
By the time you’re done, you’ll be a preview expert. Let’s dive right in!
Why does Lightroom build previews?
Every file in Lightroom has a preview – but why? Why is this necessary, when other programs – including Photoshop – don’t use previews at all?
It has to do with Lightroom’s unique form of editing. You see, Lightroom doesn’t change the pixels of your photos directly; instead, it keeps a record of the changes you make in the Develop module, then each time you view a photo, it serves up a preview with all your edits.
In other words, no matter how heavily you edit a photo, Lightroom leaves the original file unchanged. It uses previews to display the adjustments. Then, when you export an image, you get an entirely new file with all the edits baked in.
Lightroom previews in the Library module
The Lightroom Library module uses previews to display your photos so that you can then view, zoom, rate, and flag them.
Note that there are several types of previews you can build in the Library, and each one offers slightly different functionality:
- Minimal previews
- Embedded and Sidecar previews
- Standard previews
- 1:1 previews
There’s also a fifth type of preview, Smart Previews, which I also discuss below.
Minimal previews are the smallest previews Lightroom offers.
Using Minimal previews – as opposed to the other options on the list – will save space, and Lightroom can add minimal previews fast (they actually come straight from the original image file). But the results won’t be high quality.
So if you need to import hundreds of photos and you’re in a rush, Minimal previews might make sense. Later on, as you view and edit your images, Lightroom will spend time creating larger previews.
Unfortunately, creating larger previews eats up processing power, so if you want to view your photos at the highest-possible quality without lag, consider using a different preview type.
Embedded and Sidecar previews
Like Minimal previews, Lightroom’s Embedded and Sidecar previews come directly from the original image file. They’re bigger than Minimal previews, but not much bigger, so they’re quick and easy to add to the catalog.
But Embedded and Sidecar previews aren’t sufficient for closer viewing or editing. If you tell Lightroom to use Embedded previews, then you browse through the Library module, you’ll notice delays as Lightroom builds its own better-quality previews (see the section on standard previews, below).
So while these previews are helpful when you’re looking to quickly import your photos, they’re not ideal if you plan to spend significant time browsing and organizing your files.
Standard previews are designed for everyday Lightroom use. They look good, they offer a beautiful rendering of an image, and they’re not as big as 1:1 previews (featured below).
Lightroom takes longer to build Standard previews than it does to create Minimal previews or Embedded and Sidecar previews. This is because Lightroom makes its Standard previews from scratch.
Note that, if you feel your Standard previews are taking up too much space, or you simply want Lightroom to build them faster, you can adjust their size in the Catalog Settings. I’d recommend picking the Auto option, which tells Lightroom to build previews that match your monitor resolution:
Standard previews are great, especially if you’re planning on simply viewing your photos in Lightroom. The only problem is that Standard previews aren’t designed for zooming in for close-up views; if you start with a Standard preview, then zoom in, Lightroom builds a 1:1 preview, which can cause lag.
1:1 previews are Lightroom’s highest-quality option for image viewing, because they’re full-sized previews that let you zoom into 100%. They also take the longest to build.
In other words, if you tell Lightroom to build 1:1 previews, it’ll take a long time – but when browsing photos afterward, you can zoom in with zero delay.
Another drawback to 1:1 previews is that they take up a lot of hard drive space. Lightroom handles this by discarding the preview file after a set amount of time. The default is 30 days, but you can change that in the Catalog settings if need be:
If you like to pixel peep, then it probably does make sense to generate 1:1 previews in advance. That way, you don’t have to wait while Lightroom makes the files. On the other hand, if you rarely use Lightroom’s zoom function, you might want to stick to Standard previews and only create 1:1 previews as required.
How to build the right preview in the Library module
I’ve talked a lot about these different Lightroom previews, but how do you actually build them?
There are a few ways, but the easiest is to simply select your desired preview type upon import. On the right-hand side of the import dialog, Lightroom lets you select from the Build Preview dropdown:
Remember: If you’re happy with a low-resolution preview (and lag when viewing photos later on), go with a Minimal or Embedded preview. Otherwise, choose Standard or 1:1.
By the way, if you initially create too-small previews and you decide you’d like Lightroom to generate larger files, you can always select Library>Previews, then direct Lightroom to build Standard or 1:1 previews.
A Smart Preview is a high-quality, highly compressed preview, and it differs from the options discussed above because it can be used in the Develop module.
You see, even after generating Standard and 1:1 previews, you can’t edit in the Develop module without access to the original image file. But if you’ve created Smart Previews, you can edit images – even when the hard drive containing the original files isn’t connected to your computer.
This feature lets you use Smart Previews to edit while traveling. All you need is a laptop, a copy of your Lightroom Catalog, the preview files containing Library module previews, and Smart Previews.
Note that you can create Smart Previews upon import:
Though you can also generate Smart Previews later on, simply by selecting a photo, then tapping Library>Previews>Build Smart Previews.
Lightroom previews in the Develop module
When you switch from the Library module to the Develop module, Lightroom uses different previews to display your images. Lightroom renders high-quality previews that let you see the result of actions such as sharpening, noise reduction, and portrait retouching.
Note that Develop module previews are cached rather than saved in a preview file; otherwise, Lightroom would need to generate a new preview each time you made an adjustment, which would rapidly eat up most of your hard drive space.
Now, creating 1:1 previews in the Library module makes no difference to the speed at which Lightroom renders previews in the Develop module. But if a Smart Preview exists for a photo, Lightroom uses it instead of rendering a Develop module preview – in either of the following situations:
- The hard drive containing the original photo file is disconnected from the computer.
- You have Lightroom CC 2015.7 or Lightroom 6.7 or later, the hard drive containing the original photo file is connected to the computer, and you have the Use Smart Previews instead of Originals for image editing preference enabled in Preferences (see below). Note that if you zoom into 1:1, Lightroom will stop using the Smart Preview and will render a full-size preview instead.
Smart Previews are smaller than full-size previews, so Lightroom can run faster when Smart Previews are used in the Develop module. The speed increase can be quite significant. If you don’t frequently zoom into your photos at 100% magnification, then the benefits of preferentially using Smart Previews are considerable.
Which Lightroom previews should you use?
Lightroom previews are somewhat confusing, especially for beginners. So I’ll make it easy by sharing hard-and-fast recommendations for different situations:
When you import images into Lightroom, choose either Standard or 1:1 previews. If you intend to zoom into your images while viewing them in the Library module, you definitely want to pick 1:1 previews. Otherwise, pick Standard.
If you frequently edit images while traveling, also tick the Build Smart Previews option in the Develop module. And if you rarely zoom in to 100% when editing, select the Use Smart Previews instead of Originals for image editing option in your Lightroom preferences.
Now over to you:
Which previews do you plan to use? Do you like Smart Previews? Share your thoughts in the comments below!