PROBLEM
I'm having problems with exporting/processing images.
My images have artifacts in them when viewing/processing.
Processing/viewing images is slow.
SOLUTION
The quickest way to see if Hardware Acceleration is causing these issues is to set it to 'Never' under Preferences > General. For more information, see below:
The issues described above are usually associated with OpenCL (Open Compute Language) / Metal which enables the effective utilization of thousands of computing units within modern graphics cards. For Capture One, only relatively new GPU cards have enough computing power and onboard RAM to be utilized effectively. Whilst Hardware Acceleration is designed to increase performance in Capture One, you may also find some instances when it can decrease performance instead or cause some issues while processing and editing images. Such issues usually occur on the machines which do not meet our recommended system requirements for running Capture One. You can find those system requirements in the release notes for the particular version of the Capture One software you are using.
The issues that might be related to OpenCL / Metal
- Scrambled or somewhat 'glitched' previews when making adjustments
- Crashes when processing/exporting images
- Artifacts in processed images
- Slow processing times
- Slow mask drawing
- Crash when opening Capture One
If Hardware Acceleration is stuck at 0% on initialization (Windows OS)
This is an access issue with Capture One enumerating installed OpenCL platforms. You can fix that by following the steps below:
- Close Capture One, then hold down the Windows key and press the R key on the keyboard.
- Type regedit in the window. This brings up the Registry Editor.
- Select Yes to make changes.
- Go to Computer -> HKEY_Local_Machine -> SOFTWARE -> Khronos -> OpenCL -> Vendors.
- Right-click on IntelOpenCL64.dll and choose Modify.
- Enter "1" (without the quotes) in the Value data field. Press OK.
NOTE: The name of the ' .dll ' file might differ from the one mentioned above. It usually depends on the processor embedded in your system. The path might also differ in the part Khronos -> OpenCL -> Vendors where the folder with the processor's manufacturer name might be there.
NOTE (for AMD Radeon RX 5700 graphics card users)
Delete the version-specific preferences folder:
C:\Users\UserName\AppData\Local\Phase_One\CaptureOne.exe_StrongName_y3yh4brhpfi14u41fltdrpfruizxirsn
The last part \(...)_Strongname_(...) might be different for you.
Then restart the computer and Capture One. That way, Hardware Acceleration should be fully initialized.
Learn how to find the AppData folder on Windows
Rebuilding kernels
If you have a machine that meets our recommended system requirements, you may need to rebuild the kernels needed for OpenCL / Metal to initialize properly.
Capture One 20.0.0 and later versions
macOS
Close Capture One and then delete the contents of the ImageCore folder as shown in the image below. You can find this folder by navigating to:
/Users/XXX/Library/Application Support/Capture One.
Please note, this library is hidden by default in MacOS. Hold down the option key while viewing the Finder menu 'GO' to see the Library pop up to enter the direction.
You can also enter the location directly via the Finder menu 'Go > Go To Folder' and copy/paste the following line:
~/Library/Application Support/Capture One/ImageCore
This will take you straight to the folder.
When you restart Capture One, Metal will rebuild the hardware acceleration kernels - let it finish before quitting the software. This rebuild will only need to be done once.
Windows
Similar to the procedure on macOS, delete the contents of the ImageCore folder and restart Capture One, whereby OpenCL will re-initialize.
C:\Users\User_Name\AppData\Local\CaptureOne\ImageCore
Learn how to find the AppData folder on Windows
Capture One 12.1.5 and earlier versions
macOS
Close Capture One and then delete the contents of the ImageCore folder as shown in the image below. You can find this folder by navigating to /Users/Shared/ImageCore (this can easily be done in Finder via Go -> Go To Folder menu item) When you restart Capture One, OpenCL will rebuild the hardware acceleration kernels- let it finish before quitting the software. This rebuild will only be done once.
Windows
Similar to the procedure on macOS, delete the contents of the ImageCore folder and restart Capture One, whereby OpenCL will re-initialize.
Disable Hardware Acceleration in Capture One
General guidelines
If viewing, processing, or exporting issues still occur, set the OpenCL options to Never in the General tab. Navigate to the Preferences -> General -> Hardware Acceleration (Use OpenCL for) and set the Display and Processing options to Never. Restart Capture One.
Disable Hardware Acceleration in Capture One in case of a crash at startup
Windows:
- run the script DONOT_useopencl.reg and restart Capture One (the download also contains a restore script to re-enable OpenCL useopencl.reg) Download here.
macOS:
- download OpenCL_HelpTool_21.app;
- run the app;
- you'll get an error if you didn't allow apps from unidentified developers; in this case go to System Preferences - Security & Privacy - General tab and click Open Anyway:
- in the help tool select "Disable" to disable OpenCL, "Yes" to rebuild the cache and "Relaunch" to confirm;
- you can see exactly what this script does if you control-click on the OpenCL_HelpTool_21.app, select Show Package Contents, go to Contents/Resources/Scripts and double-click the main.scpt file:
How to delete Metal kernels
NOTE: M1-macs only
Option #1 - Open Finder to the folder containing metal kernels of Capture One 15
Open Terminal and copy paste exactly as follows:
find /private/var/folders -type d -path '*captureone15*' -name 'com.apple.metal*' 2>/dev/null | head -n1 | sed 's:$:/..:' | xargs open
This command will find the folders in which Capture One 15 stores its metal kernes, and open it directly in Finder. From there you can delete the folders containing metal in their names.
Note: You can modify '*captureone15*' to '*captureoneXX*' where XX is the CO version number (e.g. 14 for CO21, 15 for CO22)
Option #2 - Show/open all folders containing metal kernels for all Capture One versions
Open Terminal and copy paste exactly as follows:
find /private/var/folders -type d -path '*captureone*' -name 'com.apple.metal*' 2>/dev/null
This will print out a list of metal kernel folders for all Capture One versions on your computer. You can then take the path printed out and navigate in Finder to that folder (this can easily be done in Finder via Go -> Go To Folder menu item), there should be 1 or 2 folders per Capture One version. From there you can delete the metal folder, you might need to go up one level to the parent folder to do so.