iMac slow, what now?

It's tricky trying to help when the your problems are stated in such a vague way (eg. "Using LR6 and PS was like dragging a sticky thing through molasses" and "LR is dog slow. Every change I make manifests itself in blocky rendering"), altho' I appreciate it's not easy to verbalise computer symptoms.

What is your level of experience/confidence with computers?
Is the problem solely with LR, or are you having problems using other apps?
Is LR slow when working with files on the iMac's internal hard drive (you've stated that all your photos are on an external drive.)
Can you provide a screenshot (Shift Cmd 3) to show us this 'blocky rendering'?
What have you done so far? We know that you've exchanged computers, flushed the PRAM and turned off LR's GPU use.

What you're experiencing isn't normal and it's tricky to offer constructive help with so little information.

Hopefully the helpful folks here will help find a solution.
 
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It's tricky trying to help when the your problems are stated in such a vague way (eg. "Using LR6 and PS was like dragging a sticky thing through molasses" and "LR is dog slow. Every change I make manifests itself in blocky rendering"), altho' I appreciate it's not easy to verbalise computer symptoms.

What is your level of experience/confidence with computers?
Is the problem solely with LR, or are you having problems using other apps?
Is LR slow when working with files on the iMac's internal hard drive (you've stated that all your photos are on an external drive.)
Can you provide a screenshot (Shift Cmd 3) to show us this 'blocky rendering'?
What have you done so far? We know that you've exchanged computers, flushed the PRAM and turned off LR's GPU use.

What you're experiencing isn't normal and it's tricky to offer constructive help with so little information.

Hopefully the helpful folks here will help find a solution.

You're correct it was a poor explanation, and you're also correct in that it's bloody difficult to explain! I'll do my best to describe what happens. Starting with the splash screen, it will sit there for 30-40 seconds before the main screen opens.
Then once I chose a photo to edit, I'll move a slider (say contrast) and I have to wait a second or two for it to take effect.

If I then choose to edit the photo in silver fx it gets worse. If I chose one of the presets, the image will "build" in blocks of pixels approximately 4" square until it's rendered. I'm not in front of the mac so I can't take a screenshot.

I tried using a file from the mac hard drive and it was the same.

I have no other apps other than silver fx and those that came with the machine.

I'm fairly confident around macs and pc's and can google most problems if I'm stuck. This one seems to be perplexing everyone though.

I hope that all makes sense!
 
This is probably rubbish but Are you sure your apps are installed on the SSD? Your description seems to indicate the Mac is accessing an external source.
 
Not sure. How would I check?
 
Umm ... well one obvious thing is to disconnect all external drives and start LR/PS. I don't have any of these Adobe apps but I thought they are all installed on the local drives not in the Cloud but it would do no harm to disconnect from the internet as well -- maybe they are checking something online when they are loading. It's a peculiarity/feature of Mac OS that apps can be installed on any connected drive and Spotlight will find them if you start apps from the keyboard as I do.

(Edit for typos)
 
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Right, so it's reading the files from the hard drive. As soon as I disconnected the hard drive, it could no longer find the file...

The splash screen is still 20 seconds + to open into the full screen. Editing seems similar, albeit a tad faster.

Editing in Silver Efex is the same. I have attached some screenshots which hopefully show the issue (Excuse the washing, I just took a snap and loaded it to the desktop) You can see the blocks rendering the shot in them. Once the rendering is done, the picture is fine. It just doesn't seem as smooth a process as my old windows laptop. And considering this machine cost me £2k I'd like some speed from it!

dyq3d2.png


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Possibly try opening files in another app (you will have Photos and Preview) and see if rendering is also slow. Since you have had 2 new machines it does not seem possible there is any fault with the machine or software and there are many reports from people using the 27" iMac for photo work and finding it great. There are other free apps you could try which might isolate the fault to the CC installation.

I too have an old Mac mini and I have trialled Lightroom (not Cloud version) and not found it slow.
 
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Try viewing your activity monitor (Applications/Utilities/Activity Monitor) to see what's going on with the GPU.

I've only Safari open and when I open LR, there's around 91% still idle.
 
This is the screenshot of the activity monitor with just Safari open. seems to be a lot of processes running, but 95.8% idle

53pzcx.png
 
It dropped from 95.8% down to 56% at it's lowest point with varying results in between. Just typing the it dropped to 84%
 
Just editing a basic picture mine doesn't drop below 85%. There must be something that's dragging the performance down?

Apple must be able to advise of basic checks. Can they not offer a remote service and check it out themselves?
 
Just editing a basic picture mine doesn't drop below 85%. There must be something that's dragging the performance down?

Apple must be able to advise of basic checks. Can they not offer a remote service and check it out themselves?

They did that yesterday, and could see there was a problem, but could not figure out what the problem was!
 
Down to 26% now. I'm obsessed!
 
Where did you purchase from Nick? What's strange of course is that this is your replacement machine, right? I think they have a duty to direct you to a local repair centre for someone to look over. If they can't diagnose remotely then that must be the next logical step.
 
Where did you purchase from Nick? What's strange of course is that this is your replacement machine, right? I think they have a duty to direct you to a local repair centre for someone to look over. If they can't diagnose remotely then that must be the next logical step.

It was bought online direct from Apple. They offer three courses of action. Replacement, Repair or Return. I really don't want to slap 15 miles to Lakeside shopping centre with the Mac under my arm (apart from the fact, it'd probably get nicked before I got out of the car park!!) I have gone with a third replacement as I can overlap the return of the previous machine, which means no downtime with my work. If this fails then I'll just get a refund and make a call on where I invest my money next.
 
Difficult to see with that screenshot as to what else is running, but for sure, your experience is not typical for the hardware you have, and if two machines have exhibited the same behaviour, it's very unlikely to be hardware based.

Starting with a blank, new machine, what are you installing and what are you plugging in to it?

I'd start with nothing and nothing, and just download and install LR and see how that works, and I mean nothing - no external drive, nothing.

Possible things giving you grief include:
  • Is the machine busy indexing a huge external drive with all your files on (Spotlight)?
  • I find with Adobe (and only Adobe), it sometimes also tries to access copies of the software on external drives in preference to the internal drive. For example I clone by main disk weekly to a backup, and when I ask an Adobe app to open another app, it often chooses to load from the clone and not the main drive. This does affect performance.
  • With regard to your LR Catalogue. Are you using an existing one? Could that be corrupt? Are you using existing previews? Could they be corrupt? Are you building smart previews for a new catalogue? That could take an age and slow your system down.
  • Are you writing all changes to .XMP files? Are those files on the external disk or your main disk? If external, is that working as well as it should speedwise?
Just seen the comments about Silver Efex being the same; kind of rules out the catalogue issues perhaps?

Could you post the screenshot of the memory tab in the Activity Monitor too? If it's affecting multiple apps, it may be that something is causing your memory to be compressed / swapped out.
 
The machine accesses the hard drive which is 2TB but only contains 256gb of photos. I have done a larger screenshot of the memory tab
Edit, yes I'm using an existing catalogue on LR. Could that be the cause of the problem I wonder?

210c0hh.png
 
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For what its worth my late 2013 iMac 2013 was being very slow, after the latest OSX - Sierra, so I went and installed OSX Mavericks now Lightroom and Photoshop run wild, no problems at all, no spinning loading wheel or anything.
 
The machine accesses the hard drive which is 2TB but only contains 256gb of photos. I have done a larger screenshot of the memory tab
Edit, yes I'm using an existing catalogue on LR. Could that be the cause of the problem I wonder?

It's quite possible

I would create a new Catalog on the internal HD and test again with an image file also on the internal drive

I run CC versions of LR and PS on a 2014 MBP 15 with 16GB of RAM and a rather full 256 GB internal SSD with no problem
 
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I would suggest it's something to do with your external hard drive rather than the i.mac ,you said a few posts back you disconnected the drive and it could no longer read the files , the way I read it then is your working from stuff stored on the external drive rather than on the actual i.mac .
And as it's happened to two machines now I would think it's where the problem lies either external hard drive ,the connecting cables ,or configuration . What puzzles me is why are you not working from the i.macs hard drive
 
I would suggest it's something to do with your external hard drive rather than the i.mac ,you said a few posts back you disconnected the drive and it could no longer read the files , the way I read it then is your working from stuff stored on the external drive rather than on the actual i.mac .
And as it's happened to two machines now I would think it's where the problem lies either external hard drive ,the connecting cables ,or configuration . What puzzles me is why are you not working from the i.macs hard drive

I actually think you're right. I didn't know/understand where Lightroom was pulling the photos from. It just never occurred to me. Since I moved the catalogue to the Mac HD and created a new one it seems much faster. Though ironically, Silver Efex is worse!
 
I tend to process these days ( on a much older slower mac) than yours ,starting in Lightroom for initial pp ,then into Photoshop for layering etc ,then finish off with nik efex ( plug in) and then applying noise reduction ( plug in) and a fully processed image if there's no cloning involved will usually take from start to finish around 3 minutes .obviously it will depend on what your actually doing .
 
I actually think you're right. I didn't know/understand where Lightroom was pulling the photos from. It just never occurred to me. Since I moved the catalogue to the Mac HD and created a new one it seems much faster. Though ironically, Silver Efex is worse!

Is Silver Efex still looking for the original location first - looking for the external drive first, then the new location - might explain why it's worse, I'd be tempted to reinstall it and see if this helps any ?
 
Or the external hard drive could be failing -- backups?
 
Lightroom queen is quite good book for explaining all this don't use LR anymore, did my head in, photos for simpletons like me is quite adequate YMMV lol
 
It could be. It's only 6 weeks old though with barely any files on it

That doesn't really make a difference.

It sounds like LR is working from the image directly from the disc, rather than loading it into memory. I don't have LR6, but it may be worth looking for a setting that instructs LR to load images into memory when working on them, or to create a folder on the system drive to store images for work, then transfer them across to the HDD when finished. Since you've spent so much on the basic machine, it might be worth picking up a 256-512GB SSD + USB3/TB caddy and using that for image storage.
 
I find the best way is to put everything on your mac then just use your external for back up storage ,with the memory you have it will take a lifetime to fill ,my macs got a 1tb hd and after a few years of shooting a couple of thousand raw files a week its only used less than a third of it .
I used to be worried about filling mine up but not any more ,good housekeeping of your l/room library will also help ,no use keep stuff you will never use
 
Did you manage to get to the bottom of the issue?

To be honest-no. I'm on the third mac and now not using the hard drive at all unless I want to save to it. Will give it another week and if there's no real improvement I'll cut my losses and return it for a refund
 
LR and PS have been buggy for me since Adobe CC and/or upgrading to El Capitan. Nothing like what you're describing but it can have 'moments', such as you can do an adjustment in LR and it takes a few seconds for it to change, whereas normally it's instant. Also when going from one pic to another quickly it can take a second or so to snap into sharpness. I've noticed this more when I'm overloading it say exporting several files then flicking through pics and then applying the off adjustment. The machine gets very hot and the fans go wild. I know I'm stressing the system though as if I look at activity monitor the CPU usage for LR can go up to 680% and over. LR takes roughly 10s to start up. I have the same issue on my iMac (5K 32GB RAM SSD, 4GHZ quad core CPU (IIRC)) and my MBP (16GB RAM SSD 2.2ghz Quad Core CPU). Performance seems to vary with every CC update.

TBH I wish I'd never upgraded from Mountain Lion. With every new OS I seem to get more glitches and more spinning wheels. I hate to jump on the bandwagon but I can't help feel that Apple really has gone downhill since Steve Jobs passed away. The main reason for me buying apple products was how smooth they are/were, but for me they're getting more glitchy. Even the iPhone now has glitches (tried 3 iphone 7's) :rolleyes:
 
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TBH I wish I'd never upgraded from Mountain Lion. With every new OS I seem to get more glitches and more spinning wheels. I hate to jump on the bandwagon but I can't help feel that Apple really has gone downhill since Steve Jobs passed away. The main reason for me buying apple products was how smooth they are/were, but for me they're getting more glitchy. Even the iPhone now has glitches (tried 3 iphone 7's) :rolleyes:
OT. I'm running Mountain Lion in a Parallels virtual machine on Sierra (for FileMaker Pro 12 which is not supported in Sierra) and I have to say everything seems as fast as in the Sierra host. This in an oldish Mac mini with 16gb ram.
Edit for typo
 
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