How to use the tethered capture mode with a Pentax K3 ?
Which version of Lightroom are you using?
As per the list of supported cameras A list of cameras that can be tethered to Lightroom. ,it is not supported for Tethering.
I use Lightroom 6.4
Have you planned development for the PENTAX Brand (the full frame arrives...)
You may request for a Feature here Photoshop Family Customer Community
Also update Lightroom to version 6.5. Keeping Lightroom Up-to-Date
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