Generating Previews?

[s_levin]

Greetings-

My newer version (1-2 year old) 27" iMac with 32 GB of RAM (see attached screen shot) takes SO long to generate previews.  I have read articles with suggested setting and still can't seem to find out what's hanging up the process.

"Use Graphic Processor" is checked.  Auto (Standard) Preview size.  Medium Preview size.

Images taken with 24 megapixel cameras.

Can anyone make any suggestions or observations that may help me resolve this problem?

Thanks.

[dj_paige]

How long does it take? Can you measure it and let us know?

What version NUMBER of Lightroom? (I want the number and not words like "up to date")

[s_levin]

2015.10.1--The latest update.  I always update the new version immediately.  Though this has been the situation for quite a few months, if not longer.  I kept waiting for updates to "correct" it.

It takes easily 5 minutes to render previews for 100 images.  Sometimes longer, especially if the process actually "gets stuck," which it seems to do also occasionally.

Thx.

P.S.  I've been on these forums for years.  Don't know why I show up as a new poster!  haha

[dj_paige]

I don't think 20 previews a minute is unreasonable, given that you have an i5 processor and 24 megapixel images.

Also, 2015.10.1 that is not the latest update (which is why I said I don't want words like "up to date")

[Jim Wilde]

dj_paige  wrote

I don't think 20 previews a minute is unreasonable, given that you have an i5 processor and 24 megapixel images.

It depends, Paige. What type of previews are we talking about (Standard, 1:1, or Smart)? Have any edits already been applied to the images? What resolution is the monitor ("Auto" setting will use the screen monitor to set the Standard Preview size, so there could be a significant speed difference in rendering Standard Previews on a 1920 rez monitor vs a 2560 or higher). Without any of this information it's difficult to offer an informed opinion about what might be a reasonable per image rendering time.

[dj_paige]

JimWilde​

The OP has answered almost all of these questions.

[Jim Wilde]

Not trying to be difficult, but I've checked through the posts (several times) and still don't see what type of previews have definitively been stated. Yes, I see that the standard preview settings are listed, and so one could maybe assume that the OP is talking about generating standard previews, but you know what they say about making assumptions. Nor is there any mention of whether the images are edited of not (which can make a huge difference), but yes we could again assume that we're talking about unedited images.....though if both of those assumptions are correct, then I'd suggest that 3 seconds per image is way too long. But it would be nice to be certain about these things, don't you think?

Yes the screen size is listed, but not the bit which influences the size of the standard previews that will be rendered with the Auto setting....the resolution.

[dj_paige]

Regardless of whether this is reasonable or not

The only ways I know of to speed up preview generation are:

• get faster hardware (specifically faster CPU),
• make sure no other applications are running
• generate smaller previews.

[s_levin]

Given the info I've provided, what is the recommended preview size for my setup?  It is currently set to Auto (5120).

[dj_paige]

There is no "recommended" preview size, the choice is up to you, depending on your needs. As I said, if you want faster preview generation, then you would pick a smaller size. (But I think that's the reason you're preview generation seems slow to you, you are generating HUGE previews because of your HUGE 5K screen) Please also keep in mind that generating smaller previews will speed up that part of Lightroom but will slow down other operations in Lightroom.

[s_levin]

"Please also keep in mind that generating smaller previews will speed up that part of Lightroom but will slow down other operations in Lightroom."

What operations will slow down?

[dj_paige · Accepted solution]

Just about everything that uses a preview above thumbnail size ... LR will have to spend time generating the preview when you want to view the photo in Loupe view, for example.

[s_levin]

In other words, spend the time to generate the largest Previews possible for your computer.

And, that is a slow process!

Oh well.

Thanks.

[s_levin]

I'm not sure what  the number for the latest update is...or was (a new one just came through Creative Cloud about an hour ago).  All I know is that I ALWAYS have the latest update and always had that (since the very first version of Lightroom that came out years ago...and the early days of Creative Cloud versions).

And I think that 20 previews a minutes IS unreasonable.  Especially since I said it was sometimes longer and gets hung up from time to time, too.

Let's put it this way....it's a lot slower than it has been (with the same file sizes) over the years.  Including with my previous 2010 or 2011 27" iMac with 16GB of RAM.  THAT is why I have been trying to resolve this problem for a while.....and why I resorted to the forum for help.

BTW, the splashplate now says 2015.12.

To a subsequent poster, I have Standard Previews.  And, Auto settings.  Perhaps the Auto setting is the problem???

Thx.