Rendering standard previews

If I import a few thousand nefs (or jpgs or psds), with 'render standard previews checked' on a PC, it does not render ALL the standard previews. If I then run 'select all' and 'render standard previews', it checks for existing standard previews and starts rendering the ones it missed on import. Even then it still misses some, and I have to repeat this about three times before it finally finds it has rendered them all.
Something not quite right?
[Standard previews set to 1640 and high quality, and imports referenced to original location]

I leave it until the bar at the top left of the screen which says 'rendering previews' has finished and disappeared, and I've also taken to using Task Manager to watch and wait until the cpu activity has reduced to zero. As you say, this can take some time.
If I then scroll through the grid of imported images, I find some that still have three dots, and which slowly disappear one by one as they are rendered. That is very tedious, so I go back to select all, wait for the metadata to be collected as shown by the bar, select 'render standard previews' - a new bar appears saying 'scanning existing previews', and when that has finished it puts up the rendering previews and starts rendering the ones that still had three dots on them. It then eventually finishes and the bar closes, but with the last lot, I had to repeat this three times before it scanned existing previews and then stopped instead of starting the 'rendering previews' bar again. Each time it added some more previews, until they had eventually been done, and there were no images in the grid view with three dots (other than the brief flash of dots as I scroll normally).
I've also got in the habit of clicking on 'all photographs' after opening LightRoom and waiting until Task Manager shows it has finished it's 'housekeeping', before starting any work. This seems to minimise 'Out of Memory' dialogs or 'Not Responding' situations.

Similar Messages

  • Stuck on "Rendering Standard Previews"

    After importing images, Lightroom (2.4) is getting stuck in the "Rendering Standard Previews" process.  I have been sitting here for over an hour while Lightroom is stuck at 6 of 117.  This happened on an earlier import as well, and I ended up canceling that process -- it was stuck on 1 of 6.
    Has anyone else seen this, and is there a fix?
    Thanks,
    Nick

    Actually, I seem to also be stuck on "Preparing File for Editing" as I try to process a photo in Photoshop.  Somehow the "process" process is getting stuck.
    Nick

  • LR5 import problem with rendering standard previews

    When I import from an SD card in LR5, the first phase of the import works fine, then the second phase is to "render standard previews" and the import process stalls at photo #3. If I double click on one of the photos, and then go back to the grid view, the importing continues fine. What is happening and how can this be overcome. Thanks,
    [email protected]

    I leave it until the bar at the top left of the screen which says 'rendering previews' has finished and disappeared, and I've also taken to using Task Manager to watch and wait until the cpu activity has reduced to zero. As you say, this can take some time.
    If I then scroll through the grid of imported images, I find some that still have three dots, and which slowly disappear one by one as they are rendered. That is very tedious, so I go back to select all, wait for the metadata to be collected as shown by the bar, select 'render standard previews' - a new bar appears saying 'scanning existing previews', and when that has finished it puts up the rendering previews and starts rendering the ones that still had three dots on them. It then eventually finishes and the bar closes, but with the last lot, I had to repeat this three times before it scanned existing previews and then stopped instead of starting the 'rendering previews' bar again. Each time it added some more previews, until they had eventually been done, and there were no images in the grid view with three dots (other than the brief flash of dots as I scroll normally).
    I've also got in the habit of clicking on 'all photographs' after opening LightRoom and waiting until Task Manager shows it has finished it's 'housekeeping', before starting any work. This seems to minimise 'Out of Memory' dialogs or 'Not Responding' situations.

  • Rendered Standard previews, Hard disk full

    Hello,
    I'm using Lightroom 4.0 on Mac OS 10.7.3 and used the "Render Standard-Sized Previews" option to generate previews overnight. I had about 30 gigabytes of free space and woke up to find my hard disk full.
    Since restarting, discarding the *1:1* previews and purging the ACR cache, I have about 10 gigabytes free, but it seems like ~20GB or so is being consumed with previews.
    My "Lightroom 4 catalog Previews.lrdata" package is only 3.53GB.
    Is there somewhere I can look for additional rendered preview files to delete them?
    Thanks!

    You may have a corrupted disk but you do not have a virus. Boot using your original system installation DVD and run Disk Utility. Repair the disk.
    If you have no Administrator accounts at all, follow this procedure to create a new, temporary Administrator account from which you can fix your normal one.
    Power on or restart your Mac.
    At the chime or grey screen, hold ⌘ and S on your keyboard to enter single-user mode.
    At the prompt, type
    fsck -fy
    and press Return.
    This is a simple check for file system integrity and is optional. It will take a moment or two to complete. Wait for it to finish before proceeding.
    Type the following exactly as written, one line at a time, each line followed by the return key. There is a single space preceding the first "slash" ( / ) character in each line:
    mount -uw /
    rm /var/db/.AppleSetupDone
    shutdown -h now
    When you restart the machine, it will take you through the entire setup and registration process all over again. When you do so, create a brand new account with Admin privileges. Give it a simple and disposable name since you will delete it later. Do not choose the option to transfer or migrate information to the Mac.
    When it completes, log in under that new account, change your previous account back to Admin, and log out.
    Log in using your old account, which will now have its Admin privileges restored. Delete the throwaway account you just created.

  • Why doesn't LR let us use embedded/standard previews (at least optionally)?

    I bought LR but cannot commit to using it mainly because it is too slow importing and browsing previews but also because LR's previews are worse than the embedded previews in RAW images or JPGs as displayed by other standard programs like Photo Mechanic, Breeze Browser or ADCSee.
    I shoot Canon RAW (then convert the CR2s to DNG) and occasionally JPG (1DMkII) but I get hundreds of images from friends and family, mostly JPG, taken with many different cameras. The vast majority of these pictures look terrific in PM, BB or ACDSee, etc but they look significantly worse in LR. LR renders its own previews from RAW files instead of using the excellent embedded preview that's already there and LR also somehow changes the JPG preview so that it looks bland and off color in comparison to the same image viewed in PM, ACDC or BB on the same computer. I assume LR's color management or color space is what changes the previews (and thumbs) so they look different (bad) in LR than they look in other standard programs.
    Why can't we at least have the option of using embedded previews in LR and display them normally like PM, BB and ACDC. Then LR would be fast (like PM, BB and ACDC) importing and displaying previews and we would not have to fiddle with exposure or color adjustments to get decent previews. Yes, I can get LR to just about match (sometimes exceed) the image quality of other programs but only with massive fiddling with individual images (the camera calibration controls are not sufficient by themselves) and that is a massive pain in the butt.
    I, of course, have read many posts about color management. But I refuse to buy expensive color calibration tools and go through that expense and aggravation just to accommodate LR. My pictures already look great in PM, BB, ACDSee and web browsers and on other non-color managed computers. I think LR should be able to be operated in a standard manner so it is consistent with other standard software. The fact is that the vast majority of all amateur photographers, even pretty serious folks, do not hassle with color management because standard software displays very nice images already.
    Another point. Some folks like to use Canon or Nikon or other RAW converters instead of Adobe's (for all or some images). If they develop their RAWS in DPP or Capture NX, etc, then import the images into LR, LR renders its own previews which disregard the work done in the 3rd party converter. This is pretty annoying and virtually prevents such folks from using LR. Other programs that use the embedded previews display the adjustments made in 3rd party RAW converters very nicely.
    Regards
    Bill Wood

    Thanks for the replies. Sorry I could not respond sooner.
    Nobody addressed my question. Why is there no option in LR to use embedded previews in RAW files and why is there no option to display JPG previews in a standard color space, presumably sRGB, like other standard software - Photo Mechanic, Breeze Browser, ACDSee, etc, etc?
    LR's insistence on rendering previews from RAW files makes the program too slow and it forces users to diddle with settings to get previews that look normal - meaning match what 99% of the rest of the world sees on normal non-color managed computer screens. Folks who want rendered previews and non-standard color space (ProPhoto) and all the rest of us who just want standard previews by default should both be accommodated. Just give us the option to choose.
    I just downloaded IDImager, a competing database type DAM program, for a trial. It does give users the option to use embedded previews for fast import and display or it will render previews from RAW if you choose that option. So it can be done and an embedded preview choice makes the program much faster and easier for most people to use.
    Just a few comments about the replies:
    Lee Jay said LR doesn't use embedded previews because:
    "Correct...that's because it's a RAW converter and must display what you'd get from a RAW conversion."
    Well, with respect, I cannot agree. First, LR is not just a RAW converter, its much more. If it was that limited, I never would have bought it and neither would anybody else. I already have ACR in Photoshop. Second, it is not mandatory that LR render previews from RAWs. It could optionally use embedded previews if that option was offered. Why do some folks lobby for lack of flexibility? I bet even you naysayers would use embedded previews sometimes, like when you want speed to show pictures to your family, friends and don't need to fester over image adjustments.
    Lee Jay also said regarding the difference between my JPG previews in LR vs. other standard software:
    "That is likely the fault of your monitor profile, which LR uses and the other programs (probably) don't. It could also be caused by you having "automatically apply auto tone" set, or by applying a preset on import."
    No, it LR's fault, period. Every other program I have ever used displays my pictures just fine (Photo Mechanic, Breeze Browser, ADCSee, etc, etc, even Windows free Picture and Fax Viewer works fine. Yes, I can diddle with LR's settings and get nice previews but I don't want to diddle with every image. And it ain't my monitor profile - I can delete it or change it and the issue remains. LR makes different previews from standard software because it renders previews from RAW data and uses a non-standard color space. Camera calibration (or presets) is not a reasonable solution for everybody. I have several cameras, my kids have many different cameras, friends have different cameras and I get images from all these people - so I have a ton of very different images in different lighting and I am not about to setup numerous different calibrations or presets to see previews in LR when I get excellent previews from other standard software that uses embedded previews and produces great previews with no work whatsoever. All I am suggesting is the option to use embedded previews and a standard color space. Again I must ask why do some folks argue for lack of flexibility?
    John McWilliams said about LR's power:
    "The neat thing is you can make the image look just about anyway you want without loss of quality."
    I could not agree more - LR is a good program! But, I don't want to diddle with every image. Most of them are fine, in fact, terrific right out of the camera. I just want to see them faster and I want them to match what other people see on standard non-color managed computers. If PM, BB, ACDSee and others can do it, so can LR.
    David Edwards said:
    "The images that I want to see in the Library section are RAW images with all the adjustments I have made to them and certainly not the embedded JPGs. If I wanted to see those I would have shot JPG."
    This is fine and no doubt makes perfect sense for David's workflow. But, why advocate against an option to use embedded previews for those who would find that useful? I too shoot only RAW with my DSLR cameras because I want the best images and the ability to use all of LR's (or DPPs) conversion powers when appropriate. But, as I said above, the vast majority of my embedded previews are good enough right out of the camera as viewed in PM, BB or ACDSee so I don't need to make any adjustments. :) Only LR creates a problem my rendering less than desirable previews by default. I also want to note that embedded previews do, in fact, display all changes made in LR and I cannot tell any difference in quality on screen between embedded previews and rendered previews when I adjust the LR version to match the default embedded preview and compare them side-by-side in LR and PM, for example.
    David also asked:
    "Do you need a RAW converter or an application to display images?"
    Both. Preferably in the same program. LR is supposed to be an all-in-one solution. It certainly will be when it gets more mature, I hope. I am a amateur so my main need is to see my pictures. I like them and enjoy them but LR is too slow importing and displaying thumbs and previews in Library mode and its previews usually need adjustment. So right now I am forced to use PM, BB or ACDSee all of which are way faster importing and browsing images and they use embedded previews that are fine, even excellent, by default.
    I think Adobe is missing out on a significant number of potential users because LR does not provide the options I am requesting. I am certainly not the only person who wants faster importing and browsing and previews that look good by default. And, as I mentioned before, folks who use other RAW converters are also excluded since they cannot see the changes they make before importing images into LR because LR will not display embedded previews.
    Regards
    Bill Wood

  • Can you generate 40,000 standard previews?

    Is there anyone using LR 2 on Windows with a catalog greater than 40,000
    images who can delete all previews and then generate all 40,000 standard
    previews in a single step without encountering a performance problem?
    Best,
    Christopher

    I've rendered 70,000 images several times in LR, but have never succeeded in one run. It usually takes two or three runs to complete all of them. On my V64, it doesn't hang, it just goes into 'warp' mode and pretends to render them (according to the progress bar)in a fraction of the normal time. Re-running it shows tens of thousands still left unrendered. But after two or three runs, it gets there. Adobe knows of the problem on my V64 system, but filling in their bug report with details of your system might help them.
    Bob Frost.

  • Weird Standard Preview Problem

    I had posted elsewhere about a problem with the "standard previews". Basically they can be there at one point and "POOF" they are gone the next time I open a particular folder. (My settings were 1440 and Medium.) Even within a folder there can be some that show the preview fine and some show previews that look like a very small JPEG file (and badly compressed to boot).
    It was suggested that generally closing LR and restarting it generally solves this problem - nope did not help.
    Any suggestions - aside from deleting the files and importing them all over again?
    Thanks,
    Steve

    Hi Hal,
    Yes, I have tried Library//Render Standard Previews. It occassionally seems to be doing something. Even tried putting the particular DVD back in the drive, selected all the photos in that particular directory and then selected "render standard previews". Nada - nothing changed.
    Even tried changing my preview settings (from 1440/Medium to 1600/High) and no difference.
    Thanks
    Steve
    BTW - If there is some "rendering going on in the background", then Adobe should have explained that we need to leave the DVD/CDR/Source Disk in longer after the program indicated (by the progress bars at the top) that the importing/rendering is completed.

  • Imported images w/standard previews problem

    I am just starting with LR and very impressed with the program.
    Most of my image files are stored on DVDs and CDRs, so I liked the idea of having the previews in LR so I could look for an image and then find the appropriate disk.
    My problem is I will insert a DVD, click on Import and check "render standard previews" and walk away. When I return, the job is completed and I take the DVD out of the drive. When I come back to LR many of the images (both the thumbnails and the rendered previews) are not there. All I see is a grey box.
    What am I doing wrong since I assume this is not the way the program is supposed to work?
    Thanks,
    Steve

    Geoff: Settings are 1440 and Medium Quality. It seems to occur more often if I do the rendering AFTER importing, instead of at the time of importing the pictures.
    Svlists: Yeah, generally that does solve the "grey box" problem, but not all the time or for all the missing images.

  • 1:1 Rendering of Previews

    I'm confused about rendering 1:1 previews. When would you want to do so? It's my understanding that LR generats them when the are needed, so why generate them in advance? Should I just check the box to use previous previews generate on import?
    I've tried to generate them in advance, but they are taking many, many hours to do.
    Guidance and insight appreciated.
    Thanks!
    Reid

    Jim,
    I had some correspondence with Geoff, although they were posted in the forum. He emailed me:
    Reid, I do not use 1:1 previews for my library, only when LR generates them.
    I do have standard previews set to 1680 as that is bigger than my screen size, this works fine for me and keeps the disk space taken for the preview file optimised.
    It can take some time to generate them depending on your library size but once done it is done, of course I have it generating the standard previews on import now.
    I wrote back:
    So if my display is 1152x864, then I sould set my preview size to 1680?
    What about quality?
    What about when to delete 1:1 previews?
    What about my existing images already in LR--do I need to delete and re-import images?
    His answer:
    So if my display is 1152x864, then I sould set my preview size to 1680?
    Yes that's about right
    What about quality?
    I use medium and that appears ok for me.
    What about when to delete 1:1 previews?
    I have that set to one day, again has not affected anything I do
    What about my existing images already in LR--do I need to delete and re-import images?
    In library, all photographs,select all, in drop down menu select previews> render standard size previews. That will build them all, then have them generated on import.
    That's what my home computer is doing now.
    Reid

  • Lightroom pictures blurred in Library module - Rendering: Larger Preview...?

    I am using the latest version of Lightroom running on a system using Vista Ultimate 64bit OS, an Intel Core i7 processor, 12 Gb of ram and two nVidia GTX295 video cards.  I problem that I am having is in the Library module, where, when I move from picture to picture, some pictures, at random, will load blurred.  The caption, in the lower center of the picture starts with "Loading from Previews" then goes to "Rendering: Larger Preview," and it stays there.  I can move to another picture which may or may not load properly.  This issue does not seem to affect the Develop module; pictures which load blurred in the library mode are crisp and clear in the Design module.
    I did not have this problem running Windows XP!
    Any suggestions to address this issue?
    p.s. I have read a previous thread which suggested that deleting the preference file might be a solution.  I have done this, without success!
    jwp

    My suggestions would be to backup and check the integrity of your catalog, to render standard previews for all images, and if necessary to delete the previews file and directory.

  • Standard Preview size/quality Lightroom 1.1. (how and what)

    I'm working on a Macbook pro, with hi-res 17" screen 1920x1200. In most manuals, tutorials etc. it says that you can "set the standard preview size fitting for your screen".
    I'm looking for some more background info on the standard preview, to decide which setting to use(if somebody has other criteria to keep in mind please do say so):
    1) What is the difference in size of files for the different combination of options (pixel/quality). Does somebody have a list.
    2) What is the actual difference in the quality options
    3) In which modules is the preview size used (also in development and slide show?)
    4) Are they also used to generate the thumbnails from? If so, does a higher standard preview size reduce the performance in library mode because it as to shrink bigger files for these thumbnails?
    5) what happens if I would use the smaller, let's say 1440 preview and then decide to view the picture full-size, in library or slide show
    6) What would be the size (in pixels) on the normal main window in lightroom on my 1920x1200 screen. if it is about 1440 (might take that one)
    Last question of course: What standard preview size / quality should I use on my 1920x1200 screen??
    Thanks in advance for all your thoughts!

    As to standard preview size and quality, try 1440 and 1680 and Med and High quality and see what you like best. You will probably choose 1680 size for your screen running at 1920x1200. That will let you run LR full screen where the image size will be close to the full size of your monitor. You can try 1440 too but I doubt that you will see any performance improvement. I have tried both sizes on my 1600x1200 monitor and I see no difference in quality or speed.
    Try both Med and High quality and see if you notice any difference in your preview quality or speed. High will make your preview folders bigger which might be a factor if you have limited hard drive space.
    Don't think preview size has anything to do with thumbs. Standard previews are separate from 1:1 previews so you can always zoom in and LR will generate a full size preview.
    In short feel free to experiment with various settings in LR. Good way to learn the program and you will know what works best on your particular computer.

  • LR 5.0 slowly in rendering import previews (RAW/Canon 6D)

    Hi guys,
    does anybody know s.th. about slow rendering imagepreviews in the import dialogue?
    My LR 5 is as slow as a snail generating those previews.
    Importing my RAWs form the EOS 6D (saved on a 95MB/s 32 BG SanDisk Extreme Pro) it renders only the 12 or 24 displayed previews and leaves out the rest (the next only when I'm scrolling down). For 12 images LR5 needs 8-10 seconds. LR4.4 does the same process for all 150 RAWs in 1-2 seconds.
    It doesn't matter if I want to import to my workstation (Dell Precision T1650, 8core Intel Xeon E3-1240 V2, 16GB RAM, 64bit) via USB 3.0 (Reader & Port) or to my laptop (Dell Latitude E6400). So it must be LR, not my hardware.
    Are there known issues with the Canon-RAW format? I just updated EOS firmware to 1.1.3, but the renderspeed stays the same. For 1 image 3-4 seconds single...
    @ Adobe-Experts: Could you please look after this very soon. Importing to different catalogs is not fun...
    Thanks,
    Ralf

    Hi
    I'm having a similar problem when importing Nikon NEFs into LR5 (true for two different cameras, D800 and D300). Rendering of previews is a) very slow (compared to LR4.4 installed on the same machine) and b) often incomplete, i.e. not for all files on the card a preview will be rendered (empty frames are displayed). Sometimes, scrolling the preview panel up and down remedies this, but there have been occasions where apart from rendering the first few previews, all the others remained empty no matter what I did. The irritating thing is that I have not found a pattern to this behaviour which would allow to find a root cause or which would allow a workaround.
    Computer: i5-760 CPU, 8GB RAM, Win7 premium home edition. LR5 installed on a different physical drive than the catalog and pictures, and the cache file is yet on another drive.
    I'm pretty confident that this is due to some issue in LR5 as importing with LR4 (or earlier versions, for that matter) showed none of these issues.

  • PDF Font Rendering in Preview/Safari on Mountain Lion

    Since upgrading to 10.8.2 a few days ago, I have been unable to read any of the PDF  statements provided by my bank.  To be clear: there was never a problem reading these statements in 10.5, 10.6, or 10.7.  The files are not corrupted, nor are the fonts embedded within them.  The copies I have saved locally display font characters as boxes of varying colors and sizes rather than actual letters/numbers.  The same is true of new copies of the same files I've downloaded from by bank's servers.  Observe:
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    ....which is less than useful.
    This PDF, and all the others affected by this issue do render properly in Adobe Reader 10.1.4 -- but that's not the point.  I'd much rather use Preview.  Has anyone else encountered this issue and solved it?
    Thanks.

    Indeed, wiping out the caches is not a permanent solution.
    I found a couple of threads in some tex newsgroups that discuss this problem. There doesn't seem to be a resolution. There was some discussion that Latex Equation Editor is no longer being developed, but LaTeXIt, a similar program shows a similar font corruption problem. Fonts are fine in Preview until using LaTeXIt (or Latex Equation Editor), when they get 'corrupted'. By that I mean that documents viewed in Preview often come up sans-serif, regardless of the original font, and often special characters, such as arrows above letters (indicating vectors) disappear. Keynote files that use those characters (from, for example, using LaTeXIt under Tiger) show corruption. Rebooting (and possibly simply logging out and back in) 'cures' the problem, ie, Preview and Keynote are once again happy. During all this, Acrobat is always happy.
    This is kind of painful, since I give physics lectures using Keynote, and things like integral and summation signs and vectors and such are kind of nice to have around.
    Someone has got to know what is going on!

  • Does anyone know why I get varying file sizes when I save a jpg (with same settings-None, 12, base "standard", preview checked) from PhotoshopCS5?

    I opened a .psd file (300 ppi, CMYK, .jpgs (1626px x 2130px), I saved it as a jpg (None, 12, base "standard", preview checked).
    I then closed the original .psd file.
    I repeated those steps on the same file and saved a series of 6 .jpgs.
    Of those 6 files, I received 2 large files (6.2MB) and 4 smaller (3.2MB) files.
    My coworkers who were having trouble opening some of my jpg images in Windows Photo Gallery on Vista OS were able to open the smaller files but not the larger ones.
    Do you have any idea why the same settings would give me different file sizes from CS5?
    Is there a way I can make it consistently keep the smaller more compatible version?

    How well a image data compresses depends on image content.   Image with High detail do not compress well image will little detail will compress well and the file size will be small. Compare a image of a blank white wall to a wall with a black and white checker board wall paper.  One is all white it white no other detail  to detail the other has squares that vary in size because of perspective angle and distance a lot of detail must be recorded.
    I do not know why they can not open some of your images. File size should not be an issue.   All your image decoded are the same size  Width number of Pixels Height numbers of pixels background layer only for these are jpeg files.

  • Standard Preview Size/Preview Quality

    This may be a silly question, but in Library mode, under Edit>Catalogue Settings>File Handling, you have options under Preview Cache for 'Standard Preview Size' (1024/1440/1680/2048/2880 pixels) and Preview Quality (High/Medium/Low)... but what do these settings actually do; I've tried changing them & not noticed and difference??

    Les_Cornwell wrote:
    Thanks again Rob
    You bet .
    Les_Cornwell wrote:
    I've tried all the different size options, namely 1024 through to 2880 & low/Medium/high and none make any obvious difference at all.
    So are previews only created as required when you view a picture in full screen mode or does LR create a preview for all your files?
    Every image you look at in Library module comes from the (library) previews, there are up to 8 possible jpegs:
    * a tiny thumbnail in root-pixels.db
    * up to 7 jpegs ranging from small to 1:1 in the "preview pyramid" (each smaller is half the dimensions of it's bigger sibling).
    Try this with a 10 photo test catalog:
    If you have a big monitor and set standard preview size to 1024, then (with Lr closed) delete all previews, then restart Lr and wait for all the "..." indicators to be extinguished (indicating standard previews have been built), then step from photo to photo in loupe view with all panels collapsed (loupe view "real-estate" maximized), you should see "loading" indicator, since it needs a bigger preview than you've got built. What it will do then is build 1:1 previews and all the smaller ones along with it, which is suboptimal from a performance point of view. If you try and zoom in to 1:1 after the "loading", there will be no additional loading, since 1:1 previews were already built.
    Then, repeat the test with preview size at max - no loading indicators, right? (when stepping in loupe view after standard previews have finished being built, I mean). Except now if you try to zoom in there will be "loading", since 1:1 preview were not required to display the loupe view, they will need to be built for the zoomed (1:1) view.
    The only difference between big enough and too big will be an ever-so-slightly greater lag when stepping in the loupe view and no 1:1 preview exists (when preview is too big I mean), since it's loading a bigger standard preview than is actually needed. Reminder: if preview is not big enough, there will be an ever-so-slightly bigger lag when stepping in loupe view too (e.g. vs. just big enough), since it's using the 1:1 preview instead of standard (which wasn't big enough). So, tester beware... (somewhat counter-intuitively, in some cases, it will be faster loading a preview when settings are, in general, too big, because it can get away with loading the next size down, which is an even better fit, e.g. if image is cropped just so - all of these little nuances make it especially tricky to test & evaluate, so consider doing initial tests using uniform-size uncropped images, to reduce the number of variables - it's confusing enough as it is ;-}).
    Note: as previously mentioned, there is considerable complexity (and bugs) in the preview system, and I may not have described it perfectly, so it wouldn't surprise me if your results were not exactly like that, but I just went and retested on my system, and what happened is exactly as I described above (win7/64), as I read it anyway...
    Regarding quality, you should see difference in some photos not others, but ONLY if it didn't resort to the 1:1 preview which may be higher quality than the standard and is independent of the standard quality setting. (I think somebody may have stated that you'd need to zoom in to see differences in standard preview quality settings, but that is wrong - the only way to see differences in standard preview quality settings is if you are in fact viewing standard previews, which you aren't when zoomed in to 1:1, and anyway it can be ellusive - see paragraphs above...).
    PS - If you want to compare jpeg quality of standard previews, one way is to export them using PreviewExporter. Again, it's tricky, since you need to assure you aren't exporting a scaled down version of the 1:1 instead of a true standard preview. After exporting you can compare outside Lightroom, so you don't have the "preview of a preview" issue going... I use Beyond Compare by Scooter Software for doing objective comparison of like-sized jpegs, but you can compare subjectively using any ol' viewer, e.g. as built into OS.
    Too much?
    UPDATE:
    Les_Cornwell wrote:
    does LR create a preview for all your files?
    No - they are created on an as-needed basis (thus the reason we hear many complaints about how stale or non-existent previews should be built in the background, to minimize "loading" in library module, e.g. after making dev changes to a large bunch), but note: standard previews may be considered "needed" when thumbnail is in view in grid or filmstrip (but not considered needed if thumbnail is off-screen, even if existing in filmstrip and/or grid).
    R
    Message was UPDATED by: Rob Cole

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