SLOWWW pano merging

[hyycc]

Using updated LrC CC for 13 NEFs from Z7, shot handheld.

It's been cranking for over an hour now and the status bar isn't even 50%.

This is on a 2017 iMac with i5, 24 GB of RAM, Fusion drive.  The RAW files are on an external USB 3.0 drive.

I've been using Pano merge since it came out a couple of years ago.  It's progressively gotten worse in terms of time it takes to complete the merge with each successive CC release.  More failures than there used to be as well.

I will also say the performance was much better with D750 NEF files.

But while this merging operating is going on, it pegs my CPU.  Yet the resulting pano DNG files are several hundred MBs at a minimum and often over 1 GB.  The individual NEFs are around 60 MBs.

So how does this get improved, all SSD in the chain?  Upgrade to an ARM processor Mac?  Switch to Windows with some $1000 graphics card?

Obviously prefer to merge in LrC.  But I swear, I could send my NEFs to a dedicated stitching program, which I haven't played around with in a long time, and get the results back and re-edited in LrC much faster.

Got to be faster than going for well over an hour (and running, though I wouldn't be surprised if this merge operation fails).

[johnrellis]

For a point of comparison, you might try doing Photo > Edit In > Merge To Panorama In Photoshop, to see if that's any faster on your machine. 

" 13 NEFs from Z7 ... Yet the resulting pano DNG files are several hundred MBs at a minimum and often over 1 GB."

Is this larger than you expected?  With 13 NEFs of about 60 MB each, we'd expect the merged DNG to be very roughly on the order of 13 * 60 = 780 MB.

[hyycc]

Well I canceled after about 1.5 hours.

It showed a sync error on the pano file, which didn't even get created.  I only manually sync my collections so don't know what that error is about.

Restarted and it finished in about 15 minutes.

So maybe it was a glitch but still a lot slower than it used to be.

[dj_paige]

So you find it unusual that pano merge on 45 megapixel images is slower than on 24 megapixel images? I don't find that strange at all.

[hyycc]

No, not unusual.

What's unusual is the same 45 megapixel images taking longer to merge with newer versions of LrC.