Removing channels from recordings to reduce file sizes

[neuronikki]

We are recording extremely long data sets from multiple animals and would like to minimize file size by removing channels not in use. However when we attempted to do this by putting the channel map before the Record node in the signal chain, our files were corrupted/damaged/unusable, but when the channel map follows the record node in the signal chain, removed channels aren't visiible in the GUI but are recorded. Is there a better way to record from fewer channels to reduce our file size? Thank you!

[medengineer]

The Record Node has a built-in channel selection interface for selecting channels to write to disk. Once set, the channel configuration cannot be modified during a recording.

Placing the Channel Map after the Record Node does not affect which channels are written to disk since the Record Node is upstream of the Channel Map.

While not ideal, using the Channel Map before the Record Node to disable channels should not have corrupted any data. Can you post the settings.xml file that caused this? If possible, can you also send a link to the data? We may be able to recover if necessary.

support@open-ephys.org

Thanks!