After installing the update to Lightroom 2015.8 while using the Adjustment Brush my iMac and external HD have cut off about 10 times in the last 70 days. In about an hour to two hours by using the power button on the iMac you can get it to turn back on. Any ideas or thoughts. Thanks
"Cut off" doesn't really mean anything to me, do you mean "power off"? Or does the pointer freeze? Or does the Finder crash? Have you tried the Force-quit app in the Apple menu, or right-clicking the Finder dock icon and hitting "relaunch" (twice)? Sounds also like you should run Onyx. Google Onyx, download, install in Applications or Utilities folder. Launch it by Right-clicking and saying "Open", then Open, and run the full Automation tab. You may have a corrupt cache or application state, Onyx will delete it.