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A Refresher on Image Previews
It’s easy to develop a routine of doing something the same way over and over again without considering how effective it is. Using Lightroom is definitely no exception. How you choose to handle initial previews has a direct impact on how responsive Lightroom is when you examine a collection of images. Generating standard and full size previews one-by-one while working through hundreds of photographs can be maddening. The initial preview settings are found near the bottom of the Import Photos window. Let’s take a peak at the four options available to you:
- Minimal Preview Lightroom imports your digital image files as quickly as possible without worrying about rendering previews. In most cases, Lightroom will display low resolution thumbnails of the images as they are imported. This is the fastest option for importing your images into the catalog; however Lightroom must build higher level previews if you want to examine the images more closely causing an impact on performance.
- Embedded and Sidecar Preview
Lightroom renders previews already present in the image or sidecar file (depending on the image format). Oftentimes embedded and sidecar previews are inaccurate so it’s wise to consider them a general starting point for rating and processing. This option should provide you with a slightly better preview than Minimal; however Lightroom may need to rebuild the preview causing an impact on performance. - Standard Preview
Lightroom renders new previews large enough to fully view the images in Loupe View (E). This should enable you to rate, sort and cycle through your shots more fluidly. Lightroom must still build 1:1 previews each time you zoom in and view an image at 100% or higher. Selecting Standard size preview strikes a good balance between importing images in a reasonable amount of time while still generating large enough previews so that you can begin processing the session. - 1:1 Preview
1:1 is the mother of all previews! Importing images using 1:1 Preview usually takes significantly longer and increases the size of your catalog; however you will be able to zoom in and view your images at 100% almost immmediatly. If you elect to render your images 1:1, Lightroom will focus on creating Standard size previews first and then come back to build the full size previews. This convieniently allows you to start examining and rating your images while Lightroom works in the background building the larger previews. Directing Lightroom to render 1:1 previews should give you the most responsiveness while cycling through and viewing your images, especially if you routinely view your images close up.
Note: Choosing to render Standard Previews forces Lightroom to rebuild the image preview. It is also worth pointing out that noise and sharpness are not accurately represented in Standard Previews. You must render 1:1 Previews to view actual noise and sharpness detail.
Which Initial Preview Should I Select?
The answer to this question really boils down to preference. Unless you are simply trying to import your images into Lightroom as quickly as possible (e.g. traveling with a laptop), I recommend choosing Standard or 1:1 Preview. Both of these options force Lightroom to generate new previews (which may be more accurate than the preview that is embedded in the digital image files). Next you must decide which of the two previews are best suited for the type of work you do. If you rarely work on every image you import, then electing to render Standard size previews is probably appropriate. For example, I usually import landscape images as Standard previews since I usually don't work on every shot in the series. Each time you zoom in to examine an image; Lightroom will build a 1:1 preview on the fly. You may have to wait a few moments while each 1:1 preview is built, but you are not unnecessarily creating high resolution previews for every image (which increases the size of your catalog).
If you carefully examine and process every image, then you will probably save time (and frustration) if you direct Lightroom to render 1:1 previews. In most cases, rendering 1:1 previews will help reduce much of the lag associated with zooming and represents the most accurate preview of your images. I usually import all the images I take from portrait sessions and weddings using 1:1 preview.
Rendering higher quality previews should help you to scroll through the Filmstrip more quickly; however remember that your system’s processor speed and memory also have a direct impact on performance.
Additional Considerations
There are several other important factors to keep in mind about previews. First, you can always generate previews after your images have been imported. In the Library Module go to Library > Previews and select “Render Standard-sized or 1:1 previews.” This is handy if you just need to quickly import your images into Lightroom and plan to work on them later.
You can also adjust the Standard Preview size and quality. Go to Edit > Catalog Settings (Lightroom > Catalog Settings on a Mac) and select the File Handling tab. A good rule of thumb is to consider the resolution of your screen to determine the Standard Preview Size. For example, if your screen resolution is 1600x1200, it’s not necessary to set the preview size to 2048 pixels. My experience has also been that changing the Preview Quality from Medium (the default) to High doesn't seem change the overall quality in a noticeable way. I recommend trying both quality settings to determine which one works best for you.
If you choose to render high resolution previews, consider directing Lightroom to discard 1:1 previews after 30 days. In most cases, it's unlikely that you need them after that much time has passed and it insures that your catalog doesn't get unnecessarily bloated over time. Look for "Automatically Discard 1:1 Previews" and select "After 30 Days" from the drop down menu. If you prefer to manually discard 1:1 previews, go to the Library Module and then select Library > Previews and “Discard 1:1 Previews.”
It’s Your Choice
If you are importing thousands of images from a wedding, it might make sense to render 1:1 previews on the front end when you first import your images so that you can quickly zip through them during processing. Conversely, you probably don’t need 1:1 previews of vacation photos and family snapshots. Choosing the most appropriate initial preview setting really depends on the type of work you are doing - it's youir choice!
Excellent post, Steve! This is a topic that causes a lot of confusion and misinformation. Your explanation is simple and to the point.
Steve,
If you have a reasonably fast computer, there isn't a performance penalty in generating a Standard Preview on the fly.
I've been chided in the past by George Jardine for suggesting that rendering Standard previews was a necessity on import. If your computer is slow, or if your files are large, then yes, render on Import.
No matter what way you import Lightroom will always have to generate a Preview at some point, and I think computer speed is a major dictator as to when.
One point you've missed is the reason Embedded & Sidecars files is an option (and a new option compared to older versions of Lightroom). Put simply, in the selection process colour accuracy is rarely an issue when checking for focus, composition and technical correctness. Using the internal previews allows for a very speedy selection process, weeding out the rejects and then finally using rendered versions to check potential keepers. If you've time to wait on an 300 image import render, then do so, but if you're trying to get the best image from the bunch quickly, Embedded & Sidecar previews is a good option to use.
Steve, first off good post. I like how you explained each option in detail.
Second, I have the same point Sean does. If you have a fast enough computer (not everyone does), then you shouldn't notice much of a performance penalty for generating previews on the fly or zooming in to work on them. On the same token, you probably won't notice much of slowdown in importing the photos either.
I've switched to importing with Standard previews after getting 8GB of RAM, and haven't made the jump to 1:1 because there's still a sizable lag on my fast computer (I guess I'm part of the instant gratification generation)... so I save 1:1 until my final cuts. I guess it depends what you want to do faster... get the photos in there, or look at the details on them.
A great addition to LR would be to have a "embedded preview" mode for the library.
This would enable me to make my picks and delete inferior similars etc... much quicker and without having to generate 1:1 previews to check for focus etc..
I currently do this in Photo Mechanic as it displays the raw's embedded preview very quickly at 1:1 zoom.
Good article - I use "standard" now, but I'll try 1:1 next time.
One comment about "Importing images using 1:1 Preview usually takes significantly longer and increases the size of your catalog": Lightroom stores the catalog (a file with ".lrcat" suffix) separately from the preview data (a file with ".lrdata" suffix, which is really a SQLite database). I don't think the catalog file will be larger using 1:1 previews.
But, of course, Lightroom needs both the catalog and the previews, so 1:1 previews will require more disk space.
Hi I've just downloaded the trial Lightroom and I've been reading all your (very well informed!) comments, so I wonder if somebody can explain to me WHY it is necessary to import files into a 'Library'? I don't want copies of files clogging up my HDD and I'm wondering if Lightroom can work the way as Capture One does -i.e. by using my existing directory structure, not creating a new one.
With over 30,000 files in my existing directory structure, I don't relish the thought of a major reorganisation or duplication.
Any guidance appreciated!
The other thing that wasn't addressed is that apparently, the develop module still doesn't use the generated previews. Instead, the develop module generates it's own preview from the raw file each time, so if you like to crop as you rate, you're still stuck with this 3-6 second lag between images in develop module while it is "loading" the preview. Jumping back and forth between library mode and develop mode doesn't avoid the delay. That's really slowing up my raw workflow. Anybody have a workaround?
Quite informative post. Thanks.
Yes but is it possible to apply 1:1 preview after the import if originally imported at another ratio? Or do you just have to reimport the images?
You can always generate new previews by going to Library -> Previews -> Render... from within the Library Module.