# ForceRefresh

The spectrograph image that you generate by using the ClusterSGPicServe action is stored in a cache, so IDOL Server can produce it more quickly when it is requested again.

Set `ForceRefresh` to `True` to generate the spectrograph image from scratch when you send a ClusterSGPicServe action. This ensures that the image is current.

Set `ForceRefresh` to `False` to retrieve the spectrograph image from the cache after it has been generated the first time.

NOTE: You can retrieve the spectrograph from the cache only if you request it in the same format (width and height) and for the same date and time.

Actions: | ClusterSGPicServe
Type: | Boolean
Default: | False
Example: | `ForceRefresh=True`
See Also: |

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