i hope Someday lightroom thethering speed will improve.
Which version of Lightroom are you using and have you tried the steps mentioned in this article Fix tethered shooting in Lightroom
Please let us know if that helps.
Could you please let us know if you are still facing the issue?
If Yes, then please try the steps as suggested above.
If No, then please let us know so that we can mark this as resolved.
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