Lightroom running sooo slow

When I started using Lightroom to process negatives it ran pretty fast. Now it is is running really slow. I have followed suggested guide lines: optimising catalogue, several times, turning off graphics processor ( made no difference). Using Lightroom CC 11 on a mac. I’m reluctant to upgrade because I had a few gliches with the new version. I adjust the neg then make a positive copy but both procedures are slow. Could the size of the catalogue make a difference ( There are over 5,000 negs in the catalogue) ? Should I adjust in Lightroom then export and delete the images from the catalogue
Any advice appreciated

5000 images is by no means a lot for the catalog of Lightroom Classic.
My LrC catalog is at 26’000 images and performance is still good.

Can you be specific about what steps take how long and what your files are?

Converting 9 images (22Mpixel CR2 files, 235 MB total folder size) takes about
17 seconds on my iMac 2019.

I definitely had a drop in performance since upgrading to LR12. Sadly enough I worked on a lot of things and the catalogue is not backwards-compatible, so I’ll have to wait for Adobe to release updates.

It’s not super bad, just introduced some annoyances like delayed screen updates (before/after in NLP) or even switching from Negative to Positive after conversion (which sometimes only shows when changing tones presets).

Hi Many thanks for your response
So I’m working on 120 colour negs. LR 11 CC, Mac Catalina. I’ve camera scanned them using Nikon D850 which gives a file size of 90 mgb as a NEF. I’m then using Neg Lab Pro in LR, ctrl n, to convert the negs and make adjustments. I then make a positive copy. (Each positive copy is about 135 mgb at 300 dpi when exported) This process is now taking 3 minutes per neg ! Originally it was a lot quicker and I haven’t changed anything.
My Lr catalogue is much larger than 5000 images - this is the folder containing the 120 colour negs.

Be most obliged if any advice could be offered

There’s on thing you could do to have an immediate impact on LR’s performance and that’s purging existing cache and increasing it’s maximum size going forward. The size of this cache can be max 200GB and solely lives on your SSD/HDD.

Here’s how:

  1. Open up Lightroom
  2. Hit “Lightroom Classic” in the top menu and select “Preferences”
  3. Switch to the “Performance” tab
  4. From “Camera RAW Cache Settings” hit the purge cache button
  5. Same place, increase the “Maximum Size” to something like… 50GB?

(5) mainly depends on the available space on your harddrive, so be sure you don’t overdo things.

…another thing would be reducing the resolution of preview images in the catalogue. That’s something you do in the catalogue settings. I’ve set mine to 1440px. That’s more than enough to know which image I’ve selected. I don’t need high res images to browse my photos.

One folder with 5000 files, no subfolders?

If so, I’d split this monster into smaller chunks.
You could also try to create a new catalog from your negative folder(s).

Although the suggested solutions are all sound and may speed things up a little, the answer is probably not the one you want to hear.

I also suffered slowdowns in LR11 and was running a MacPro5,1 heavily upgraded with a Radeon RX Vega 56 GPU, 48GB RAM and a PCIe SSD as a primary drive. Anything more than a few seconds wait is, IMHO, too long. I too, resorted to the forums for a solution and eventually got the answer I didn’t want to hear.

My LR catalogue by the way contains 40,000 images. The LR catalogue can be many times this size with no effect on speed whatsoever. It is never the cause of slowdowns.
However, both Lightroom and Photoshop are becoming ever more ‘clever’ with AI and the rest and as a result more and more processor intensive.
There is only one really effective solution - run current software on current hardware.

My old Mac Pro ran out of road with OSX Catalina and pushed me into getting a new M1 Mac. Now everything is fast again.

Thanks for all the help. I have already carried out many of the suggestions in an effort to speed up LR ( purging camera raw cache, increasing size, reducing size of preview, making sure the catalogue is optimised regularly etc) all without having an effect on speed. Still taking about 3 mins to process one image. I guess the only solution, as per Belinda’s advice, is to upgrade my computer. I have a Mac Pro 6 core Intel Xenon but with 1 tb ssd internal drive, and 64 gb of Ram. The graphics card could be updated - it has a Radeon RX 5700xt 8gb. It’s fast enough for most things.The way I’m working now is to start the conversion and then go and make a coffee rather than stare at the screen. The big issue is that, yes, camera scanning is quicker than scanning was with my Epson V750, but if post-production is taking so long any speed advantages are negated (without taking quality issues into account).

Question from a non-subscriber of Adobe CC, rooted in the past on LR 6.14 Perpetual - can you choose to stay at a particular version that suits your hardware and block any upgrades? Obviously you’d miss out on new features but then you wouldn’t need a new computer system either. Could you in fact go back to a previous version when you find, as the OP has, that everything is running slow.

I guess you could hold out for quite a time and yes, you could roll back to a previous version to accommodate the limitations of an older machine - for a time.

Eventually, however, you’re going to want one or more of the shiny new features at which point upgrading might get difficult as various incompatibilities build up and the steps between your old version and the latest become bigger and bigger. Or, like me, you end up chasing your tail with hardware upgrades (SSDs, faster GPUs, more RAM and even a newer CPU or dual CPUs and bigger power supplies) not to mention the inevitable GPU driver updates etc. As time goes on, it all gets more and more convoluted with more and more headaches to make it all work properly until finally you bite the bullet, buy a new machine and concentrate on doing something useful/enjoyable instead of trying to keep a dying computer on life support.

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Sometimes, a combination of factors will cripple an otherwise perfectly decent computer. Read through these potential causes and see whether they apply in your circumstances. All of these conditions can slow down Lightroom Classic:

1) Insufficient RAM or Unified Memory — 8GB may be too little, especially if you are running another, or more than one other, heavy duty application. 16GB is about right for most Macs. The point of diminishing marginal returns is somewhere around 24GB.

2) Running any modern MacOS off of a conventional, spinning-platter hard drive — Swapping your old spinning drive for a 2TB SSD can dramatically, SHOCKINGLY improve performance. In fact, the gain from this is probably bigger than any other change you can make. My old iMac got SEVEN TIMES faster at rendering stills and video when I doubled RAM from 8 to 16GB and replaced its 5400RPM 1TB internal drive with a 2TB SSD drive. (That was major surgery involving two kits from OWC — not something I recommend doing yourself unless you are highly detail oriented and quite used to working on sensitive electronics.)

3) Using a computer with a nearly-full startup drive — Both MacOS and Windows need room to “breathe”. By that, I mean the OS needs a large empty space it can use for swap memory or virtual memory operations. If your startup drive is more than half full, try moving data to an external drive, so the OS can use empty space on the startup drive for virtual memory.

4) Allowing external spinning platter hard drives to go to sleep — If the OS suddenly needs to read or write something on an external drive that is not spinning, everything can come to a halt until that drive gets up to speed. I don’t allow spinner drives to sleep unless the computer as a whole is sleeping. Normally, I only use spinning drives when doing backups and long term storage operations! My daily drives are all SSDs now.

5) Running a Mac that has been upgraded from OS to OS for more than three years — By that I mean you’ve dutifully updated on top of updates on top of updates. The amount of “digital detritus and debris” generated by computers over time is significant. I don’t let any of my main computers get upgraded more than three times without doing a complete backup (a bootable drive CLONE), then starting up from the external drive clone and erasing the internal drive. At that point, I install the latest compatible operating system and fresh, fully updated copies of all the software and drivers I need. Then I migrate back just the data I need for current work, keeping the rest of my data on backup drives and external working drives.

I’m running a refurbished Late 2020 M1 MacBook Air with 16GB Unified Memory, 1TB SSD, and the M1 with 8 CPU, 8 GPU, and 16 Neural Engine cores. Most of the time, I run it in low power mode. It is quite fast, at full speed, rendering 16 MP raw files to JPEGs from Lightroom Classic at the rate of more than one per second. I don’t experience any navigation lags in LrC. The only time this fan-less wonder ever got warm was when rendering a 44-minute 4K Pro-Res video (867 GB file!) to an external drive. Processing did slow down a bit then, due to thermal throttling, but I didn’t care. That was quite an unusual job, not something I do every day!

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I would agree this is more than likely a hardware issue, a Mac Pro 6 core Intel Xenon is old by computer standards. You always get a point when software stops running well.

I have a M1 MacBook Pro 2021 with 16GB ram and a 1TB ssd running LR11.5 and it exports a Nikon D850 file from NLP as TIFF in about 4secs. The TIFF file exports from LR as JPG in about 1sec.

I real don’t think the size of LR catalogues has much effect these days. I do think back when LR first came out adobe did talk about catalogue size causing issues but now adobe recommends only having 1 catalogue as catalogue size is no longer an issue.

I only have one catalogue, which has approx 357,159 images and runs without an issue. If I do a search of the catalogue it’ll return a result in about 10secs.

An Update has been released. 12.01 – Worked well for me. So far the small glitches disappeared.