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Develop module Imac crashes when converting to HDR

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New Member
Nov 10, 2019
Newark, Nottinghamshire
Lightroom Experience
Lightroom Version
Lightroom Version Number
Classic v9
Operating System
  1. macOS 10.14 Mojave
Recently my Imac 27inch, 4.2 i7 16 Gig RAM crashes without warning when I attempt to convert images to an HDR or Panorama. Otherwise stable
First thing to try is to go to the Performance tab of your Lightroom Preferences and turn off using the GPU. Then try HDR or Panorama again.
Thanks Hal, I did that and for about 20 minutes was happily processing photos and then the imac crashed again. Also, I have to unplug it from the mains to restart it. Any other thoughts?
It could be that it's overheating when Lightroom drives it hard. Do you have access to a thermometer app that will monitor your CPU temperatures?
Did you make it crash while monitoring? 40-46 is pretty cool as CPU temperatures go. I'm running out of ideas. With the whole machine crashing, it's a hardware problem. Try running diagnostics on memory.
It could be an issue with filling up all of the freespace (working storage) on the Primary drive. How much is available for temporary files and for the Swap file? How many CPUs do you have and how much RAM?
Sounds a bit like a problem I had years ago on my iMac. Ended up being either the power supply or main board. I had AppleCare so Apple just replaced both since they couldn't replicate. It would run fine for normal tasks, but when deep into editing it would just shut off. Had to pull the power cord and wait a few minutes to plug back in. Hopefully you don't have that issue. Two trips into the Apple store for repairs before the did the work.
Over 2TB of a 3TB HDD available. 1 CPU, 4.2GHz i7 and 16 GB RAM
I should have been more specific. By CPUs, I meant CPU cores. You have at least 2. Quad Core is fine, 6 or more is ideal for LR.
It does not sound like any of the usual LR limitations are an issue. Which leads us to lean more toward Hal's or Rusty's suggestions that the problem is hardware related.
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