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Previews
Your photograph files have JPEG previews.
They're embedded in the files, or are in sidecar files.
You can specify how Lightroom creates previews when importing.
There are four choices.
As you go from Choice #1 to Choice #4:
• Importing takes longer.
• The space occupied on your hard drive by the previews increases.
The import-speed and hard-drive space differences are small between
the first three choices.
Choice #4, 1:1, slows importing substantially, and takes up a
lot of hard drive space.
Many photographers use the default choice, Minimal.
That's because Lightroom can create a larger preview whenever
its required.
Choice #1 - Minimal
Lightroom creates a small preview from the existing embedded/sidecar
preview.
Choice #2 - Embedded & Sidecar
Lightroom makes the best possible preview from the existing embedded/sidecar
preview on the memory card.
Color Management
The above two choices are not color managed.
The two choices below are color managed using the ProPhoto RGB
color space.
Choice #3 - Standard
The Standard preview is what you see when you click Fit on the
zoom bar in the Loupe view.
Choice #4 - 1:1
1:1 previews are what you see in the Develop module when you
click 1:1 (100%).
1:1 previews display sharpening and noise reduction.
Choose One of the Four Choices
When you're importing some files, do the following.
1) You've done one of the following.
• You've connected your camera to your computer, and have turned
it on.
• You've connected a card reader with a card.
• You've selected a folder to import.
2) Press g to make sure you're in the Library module.
3) Click Import in the lower-left corner.
4) Open the File Handling panel on the right side.
5) Choose one of the following on the Renders Previews menu.
• Minimal
• Embedded & Sidecar
• Standard
• 1:1
6) Finish the import process.
You can set the size and quality of the previews that Lightroom
displays.
Use the size and quality that corresponds to your monitor's specification
and to your needs.
Do the following.
1) Go to Edit > Catalog Settings (Windows) or Lightroom > Catalog
Settings (Mac).
Or, press Ctrl + Alt + ,.
2) Click the File Handling tab.
3) Choose the preview size and the review quality.
• For Standard Preview Size, the default setting, 1440, is fine
for most monitors.
If you have a very large monitor, try 2048.
• For Preview Quality, the default setting, Medium, is fine for
most monitors.
If you have a very large monitor, try High.
All three quality levels are in the upper range of JPEG quality.
If you don't want to wait for Lightroom to render previews,
do the following.
1) Press Ctrl + a to select all of the thumbnails in a folder
or collection.
2) Go to Library > Previews > Render 1:1 Previews.
3) Do something else for a while while Lightroom works.
1:1 Previews after 30 Days
As mentioned, 1:1 previews take up a lot of space on your hard
drive.
By default, Lightroom deletes 1:1 previews after thirty days.
Automatically Discard 1:1 Previews after 30 Days
To change the setting, go to Edit > Catalog Settings (Windows)
or Lightroom > Catalog Settings (Mac).
Or, press Ctrl + Alt + ,.
Then, click the File Handling tab.
