Preview files are not coming up in Capture One and showing up as "Thumbnail unavailable" or having a triangle with the exclamation mark. Here we list the most common cases and their respective solutions.
Table of contents
Case 1: Custom monitor profile is missing
Case 2: Files are missing, i.e. are offline
Case 3: Thumbnails haven't finished generating
Case 4: Built-in previews in RAW files are not available or of unsupported format (Import/Cull View)
Case 1: Custom monitor profile is missing
The problem with the file preview can be caused by the custom monitor profile being corrupt or missing. Capture One is looking for the monitor profile which is set at the system level. When Capture One cannot access the monitor profile because it is corrupt or missing, there will be a system-level Profile Error causing the warning sign to be displayed in the previews.
Solution:
To resolve this issue, create a new profile or choose another profile.
Look for the profiles in the following directories:
- macOS: HD/Library/Colorsync/Profiles
- Windows: C:\Windows\system32\spool\drivers\color
Case 2: Files are missing, i.e. are offline
In some cases, the previous folder used in Capture One has been removed and the path to access the thumbnails is not valid, thus making the images and previews offline.
Solution:
1. If the folder of referenced images has been relocated, right-click on the corrupted thumbnail(s) and select Locate from the context menu.
2. Navigate to the new location of your images and hit Select. This will update or create new previews for your images.
Case 3: Thumbnails haven't finished generating
There are times when preview files stopped generating at some point due to some unknown error or if the source drive of the images referenced was disconnected.
Solution:
Regenerate previews by selecting all the images affected and then right-click>Regenerate Preview.
Case 4: Built-in previews in RAW files are not available or of unsupported format (Import/Cull View)
During import, Capture One uses the JPEG previews embedded in your image files. This makes the process faster by quickly loading thumbnails and also allows you to see larger previews, which is helpful for selecting your best shots right in the Import Images window. Some cameras, like Insta 360, may not embed a preview file, while others use a different format than JPEG for the previews — this is the case for Canon and their in-camera HDRs.
Solution:
For cameras that do not embed the preview JPEG file at all (Insta 360), you can only see the preview as soon as the image is imported.
For cameras that use HIF/HEIC format for previews, like in Canon HDR files, change the preview format to use JPEG. For instance, in Canon this setting is this:
- [
: HDR shooting
] set to [Enable]: JPEG quality