Ask Tim Grey

Today’s Question: I have a question regarding exporting a photo for a contest that specifies file size limit of 10 MB. When I go into the Export dialog [in Lightroom] I specify 10,000 KB as my limit but the file that is produced is actually 5.85MB. Why is it not producing a file closer to the 10 MB limit? Will this affect the final viewing experience?

Tim’s Quick Answer: The “Limit File Size To” setting in Lightroom’s Export dialog only establishes an upper limit. The other settings you establish will determine the actual file size you achieve, which may result in a file that is considerably smaller than the limit you’ve defined.

More Detail: The “Limit File Size To” option is only available when exporting a photo as a JPEG file. The file size limit really just provides a different way to describe the Quality setting. In other words, if you’re trying to achieve a file that is smaller than a particular size, it is easier to specify the size rather than trying to guess which setting to use for the Quality option.

However, the “Limit File Size To” option won’t guarantee a specific file size. The other key factors related to file size with a JPEG image are the pixel dimensions and the content of the image (since that content impacts the effectiveness of the JPEG compression).

If you specify pixel dimensions that result in a file size of less than 10 MB even at the maximum Quality setting, then the file will simply be smaller than 10MB. In that case, since the maximum Quality setting would be used, the only way to achieve a larger file for a given photo would be to increase the pixel dimensions.

If you specify pixel dimensions that make it impossible to create a file size smaller than the limit you specify, Lightroom will present an error that the file could not be exported because a file of the size you requested couldn’t be created.

If the contest specified pixel dimensions to be used for the files you submit, my recommendation is to export the photos at those exact pixel dimensions, and use the maximum value of 100 for the Quality setting. Only if the file were too large would I consider reducing the Quality setting. Provided you have maximized the pixel dimensions based on the submission guidelines and used a high value (80 or above) for the Quality setting, the image quality will be maintained very well.

As an aside, I also wish that the people running photo contests (or otherwise defining image submission guidelines) would stop including a maximum file size as part of their criteria. Including a file size limitation can lead to confusion for the photographers trying to submit images. If photos must be submitted as JPEG images, and if the pixel dimensions are limited to a reasonable value (such as around 2,500 pixels on the long side) the file sizes will never be extreme in the first place.

Today’s Question: I’ve adopted GoodSync as my backup solution after reading your article and viewing your video course [on GoodSync]. It works well most of the time, but sometimes I receive an error indicating that the “Sync has finished with Errors or Unresolved Conflicts”. Is this something I should be worried about? Am I doing something wrong?

Tim’s Quick Answer: This is a somewhat common issue, related to changes being made to the drive (such as by the operating system) in the background while GoodSync is running. It is probably not an issue you need to worry about, but it is a good idea to view a list of the errors just to be sure.

More Detail: When a synchronization backup using GoodSync ends with the error message that there were errors or conflicts, you can view a summary of those issues.

Conflicts occur when a file has been changed on both drives. If you’re using the one-way backup option in GoodSync, which is what I recommend, then this should never be an issue. However, it is a good idea to confirm there were no actual conflicts. You can do so by choosing View > Conflicts from the menu to display a list of conflicts for files on the drives being synchronized. Again, for a one-way backup, this won’t be an issue.

Next, you can choose View > Errors from the menu to see a list of errors that occurred during the synchronization process. In most cases these errors will be caused by the operating system doing work in the background. For example, as a Macintosh user, I often see errors related to the Spotlight search feature indexing the drive in the background while a one-way synchronization backup is in progress.

If the only errors on the list are operating system files (not your own photo or data files), then you can ignore this issue. In these types of situations you can generally avoid the errors by either leaving the drives connected to the computer for a few minutes before starting the synchronization backup, or by simply running the backup process again after receiving the error message.

I have never had an error or conflict with GoodSync that represented an actual problem with my drive or data, but I still check the list of conflicts and errors every time I see the message indicated in today’s question. If, however, you see errors or conflicts related to your actual photo or data files, you’ll want to explore the reasons for those errors, and perhaps make another backup to a different drive in the meantime just in case there are problems with your storage devices.

For those interested in learning more about the GoodSync backup software referenced today (and that I use for backing up all of my photos and other important data), you can get details through the GoodSync website here:

http://timgrey.me/greybackup

Today’s Question: I have done a complete backup to an external hard drive of my Lightroom catalog including all negative pictures and available previews using the Export as Catalog command. I have then used GoodSync to synchronize my changes to this original backup when adding/working on new pictures in Lightroom. However, if I ever have to use this backup because of a failed hard drive, new computer, etc. I have no idea how to bring all this GoodSync backup data back into Lightroom.

Tim’s Quick Answer: Actually, the beauty of using software such as GoodSync (http://timgrey.me/greybackup) to backup your photos and other data is that you don’t actually need to go through a recovery process. You can simply connect one of the backup drives in place of a failed original, make sure that the drive letter or volume label are the same as the original, and get to work immediately.

More Detail: In this case there is one additional challenge based on the way you’ve described your workflow. Specifically, it sounds like you have used the “Export as Catalog” command to create a copy of your Lightroom catalog and image files. If this copy is truly only a backup copy, however, your workflow won’t be as streamlined as it could be.

The “Export as Catalog” command is a great way to make a full one-time backup of your catalog and photos. However, it doesn’t provide a good way of incrementally updating your backup. If you used the “Export as Catalog” command to create a new data storage solution, such as transitioning your catalog and photos from an internal hard drive to an external hard drive, that’s perfectly fine. But I wouldn’t employ “Export as Catalog” as an ongoing backup solution.

You could, for example, keep your Lightroom catalog on your internal hard drive, with your photos stored on an external hard drive. You could then employ the Lightroom catalog backup feature to create a backup copy of your catalog on the same external hard drive as your photos. You could then use GoodSync (http://timgrey.me/greybackup) to backup that photos drive to another external hard drive.

This way, in the event of a serious problem, you’d have everything backed up on both external hard drives. Your recovery process could be as simple as connecting the backup external hard drive and opening the Lightroom catalog from that drive, making sure that the drive has the same drive letter (on Windows) or volume label (on Macintosh) as the original photos drive, so that Lightroom will still be able to find those photos where they are expected. And, of course, you could also move (or copy) that backup catalog to your internal hard drive as part of that recovery process.

The bottom line is that when using a synchronization approach to backing up your photos and other data, the recovery process is a simple matter (for the most part) of using a backup drive in the place of a drive that has failed or experienced other problems. No software “restore” process is required.

Today’s Question: If you print an 8×10, say, whose resolution matches your printer’s maximum resolution, the print should look good. What happens if your image file has significantly higher resolution than the printer’s capability? Does the image suffer in any way? (I assume it’s not benefitted. Is it?)

Tim’s Quick Answer: If the image contains more information than the printer needs to produce the given print size, the image data will be scaled down as needed. In general this won’t produce any significant degradation in image quality, although that “extra” resolution won’t provide a benefit either.

More Detail: Different printing methods involve different requirements in terms of image data, which translates into total pixel count. In some cases there is a specific amount of information required for a given print size, such as with a photo inkjet printer. In other cases, such as with offset press printing, the requirement isn’t quite as specific, and so there is generally a range of acceptable image resolutions to use.

Ultimately, the pixel per inch (ppi) resolution you set for an image is simply shorthand of sorts to help describe the total number of pixels in the image. For example, if we assume a print size of 10 inches on the long edge, and a photo inkjet printer that renders the output at 360 pixels per inch, then we know that the image file needs to be 3,600 pixels on the long edge to achieve optimal image quality.

If we send an image that has more than 3,600 pixels on the long edge, the printer will scale down the image data accordingly. If we send an image to the printer that has fewer than 3,600 pixels on the long edge, the printer will scale down the image data accordingly.

The alternative, of course, is to scale the image data to the optimal value before printing, such as within Photoshop. In other words, with this type of workflow we need a specific amount of data for printing at a given size. Our option is to let the printer scale the image data or to do so before printing with software such as Photoshop.

When it comes to final print quality then, the real issue here is which software will do a better job of scaling the image data. In the early days of photo inkjet printing there was a significant difference. Scaling the image in Photoshop before printing generally produced a print of much higher quality than if you started with an image at the “wrong” size and let the printer software perform the scaling.

Today, however, printer software has improved to the point that the differences are quite minimal. I still personally prefer to resize my images with an advanced software tool such as Photoshop. But the difference between resizing in Photoshop and letting your printer do the resizing will generally be relatively minimal, thanks to improvements over the years in the software that controls modern printers.

Note, by the way, that different printers render the image at different resolution values. Many photo inkjet printers use a value of 360 pixels per inch, but many others use slightly lower or higher values. An increasing number of photo inkjet printers are now available that render at 720 pixels per inch, for example. It is therefore a good idea to obtain information related to your specific printer before choosing how to scale your images.

Today’s Question: Is it necessary to save a selection [in Photoshop] if I’m going to create a layer mask based on the selection? Wouldn’t saving the selection in this case be somewhat redundant?

Tim’s Quick Answer: In general I would say that it isn’t necessary to save a selection using the “Save Selection” command if you’re going to create a layer mask based on that selection. After all, the layer mask also represents what is essentially a saved selection.

More Detail: However, there are situations where you may want to save a selection.

For example, if you will be building up a somewhat complicated selection in a series of steps, it can be helpful to save a series of selections and then merge those together into the final selection. In addition, you may find that in some cases you apply a variety of adjustments directly to a layer mask, causing changes compared to the original selection you used as the basis of that layer mask. In this type of situation you may want to save the initial selection before using that selection as the basis of a layer mask.

For most photographers and in typical workflow scenarios, however, I would say that it probably isn’t necessary to save a selection if you’re simply going to be using that selection as the basis of a layer mask. Of course, it is also worth noting that a saved selection won’t significantly increase the file size, so there isn’t significant harm in erring on the side of caution and saving selections as part of your master image files.

In those cases where you do decide to save a selection, you can simply choose Select > Save Selection from the menu to initiate the process. Enter a name for the selection in the Save Selection dialog, and click OK to save the selection as an alpha channel. As long as you then save the image as a Photoshop PSD or TIFF file, the saved selection will be included as part of the file.

Today’s Question: Should the XMP checkbox in the Catalog Settings dialog [in Lightroom] be checked at all times?

Tim’s Quick Answer: In my opinion, yes, it is best to have the “Automatically write changes into XMP” checkbox turned on. This option can be found on the Metadata tab of the Catalog Settings dialog in Lightroom.

More Detail: By default, Lightroom only saves metadata updates for your photos into the Lightroom catalog. I prefer to also have standard metadata fields updated in the image files for my photos. This provides two basic benefits. First, with this option turned metadata updates will be visible in other applications (such as Adobe Bridge) instead of only being visible within Lightroom. In addition, enabling this option provides a real-time backup of most of the metadata updates you apply.

Note that enabling this option will cause metadata updates to be saved for all supported image file formats in Lightroom. For non-RAW images (such as JPEG, TIFF, or DNG files) the actual image file will be updated. For proprietary RAW captures the updates will be written to an XMP “sidecar” file next to the RAW file.

If you apply metadata updates to a large number of photos all at once, having the option to automatically save metadata to your photo files can result in degraded performance. However, to me the benefits of having this option turned on more than makes up for any potential performance loss.

It is also important to keep in mind that not all metadata will be saved when you enable this option. Lightroom-specific features such as pick and reject flags, collections, Develop history, and virtual copies, will only be saved to the Lightroom catalog, even with the option to save metadata to your image files enabled.

Today’s Question: If I have several images captured under the same basic conditions with the same camera settings, what is the easiest way to apply the same adjustment to all of the images in Lightroom?

Tim’s Quick Answer: There are a variety of options available to accomplish this task, but I would suggest that synchronizing the adjustments in real time with the “Auto Sync” feature in Lightroom’s Develop module would be the easiest approach.

More Detail: The process of applying the same adjustments to multiple images in Lightroom is quite simple. When you want to apply those same adjustments in real time to multiple images, the Auto Sync feature provides a good solution.

The first step is to select the multiple images you want to apply the same adjustments to. You can, for example, click on the thumbnail for the first image and then hold the Shift key on the keyboard and click on the thumbnail for the last image, which will cause all images in between to be selected as well. You can also add or remove images to or from a selection by holding the Ctrl key on Windows or the Command key on Macintosh while clicking on the thumbnail for an image.

Once you have selected the images you want to apply the same adjustments to, you can choose which image you want to use as the basis of your adjustments. To do so, simply click on the thumbnail for the image itself (not the “frame” that surrounds the image) to make that the active image.

Next, enable the Auto Sync feature by clicking the toggle switch on the left side of the Sync button on the right panel in the Develop module in Lightroom. This button looks something like a light switch, and when it is turned on all adjustments you apply will be synchronized to all of the selected images.

At this point you can simply apply adjustments to the current image in the Develop module. Because you have enabled Auto Sync and have selected multiple images, all adjustments will synchronize to all of the selected photos in real time.

I do recommend turning off the Auto Sync feature when you’re finished, just to make sure you don’t accidentally apply further adjustments to the same selected images when you intended to focus on a single image again.

Today’s Question: I am embarrassed to say that I forgot to change the time on my camera during a recent trip, so all of my photos show the wrong capture time. Is there a way to fix this in Lightroom?

Tim’s Quick Answer: Yes, you can very easily correct a time zone discrepancy for your photos in Lightroom using the Edit Capture Time command found on the Metadata menu.

More Detail: For situations where the capture time error is simply due to having neglected to change the time on your camera when changing time zones, the correction is quite simple. First, navigate to the location where the affected photos are stored, and then choose Edit > Select All from the menu to select all of the photos in that location.

You can then choose Metadata > Edit Capture Time from the menu to bring up the Edit Capture Time dialog. Choose the second option in the “Type of Adjustment” section of the dialog, which is labeled “Shift by set number of hours (time zone adjust)”. Then, in the New Time section, choose the applicable number of hours you need to shift the images by from the popup at the far right. Keep in mind that you can choose a positive or negative value depending on the direction of the required shift.

When you select a number of hours to adjust the time by, the capture time for the currently active image will be presented, along with the updated time based on the correction you’ve selected. This enables you to validate that you have selected the correct number of hours to adjust the capture time by. When you have confirmed that the setting is correct, you can click the Change button to apply the adjustment. Keep in mind that this action can’t be undone, so if you make an error you’ll have to apply a new adjustment to the capture time to compensate.

It is also worth noting that by default Lightroom will only update the capture time for your images within the Lightroom catalog. If you want to save the changes to the actual image files, you’ll need to enable two options in the Catalog Settings dialog for the current catalog.

First, you’ll need to enable the “Automatically write changes into XMP” checkbox on the Metadata tab in the Catalog Settings dialog, so that Lightroom will save metadata updates to the image files in addition to saving those changes to the Lightroom catalog.

In addition, to enable updates to the capture time you’ll need to enable the “Write date or time changes into proprietary raw files” checkbox so that the metadata for RAW captures will be updated for those files, in addition to updating the Lightroom catalog.

Today’s Question: I created a selection in Photoshop for a JPEG capture, and saved that selection so I could put it to use again in the future. When I choose the Save command from the File menu, however, Photoshop prompts me to save the image as a Photoshop PSD file. I just want to save the updates to the JPEG image. Is that not possible?

Tim’s Quick Answer: No, it isn’t possible to save a JPEG image with a saved selection. Saved selections (among a variety of other features in Photoshop) can only be included with images saved as either a Photoshop PSD file or a TIFF image.

More Detail: When you open any supported image type (such as a JPEG image) in Photoshop, you can make full use of all of the available features within Photoshop for that image. So, for example, after opening a JPEG image you can save selections, add adjustment layers, and much more.

However, in order to save some of the advanced features of Photoshop as part of an image file, you need to use a supported image file format. A JPEG image, for example, doesn’t support layers, layer masks, saved selections, and other advanced features of Photoshop.

While you can use these various features with a JPEG image (or other supported image formats), that doesn’t automatically mean you can save the image in the same file format with all of the advanced features included.

JPEG images don’t support alpha channels, which are required to support the option to save selections as part of an image in Photoshop. The reason Photoshop is prompting you to save the JPEG as a PSD image is that you have made use of features that the JPEG file format doesn’t support.

So, if you want to retain your saved selections or other advanced features, you’ll need to save the image as a Photoshop PSD file or as a TIFF image.

Today’s Question: Does the Lightroom backup for the catalog also backup your photos? If not is there a way to accomplish this?

Tim’s Quick Answer: No, the Lightroom catalog backup feature does not backup your photos. While it would be possible to backup both your photos and the catalog using the “Export as Catalog” command, I recommend using a different solution for backing up your photos.

More Detail: When you use the backup feature in Lightroom, you are only backing up the Lightroom catalog, not your photos. In other words, you’re backing up the information about the photos and not the photos themselves.

As noted in yesterday’s Ask Tim Grey eNewsletter, there are some benefits to using the Lightroom catalog backup feature for backing up your catalog, including the option to check the integrity of the catalog and optimize the catalog. Therefore, it is a good idea to use the Lightroom catalog backup feature even if you have another backup solution that is also backing up your catalog.

For your photos you’ll need a different backup solution. I personally prefer a “synchronization” approach to backing up my photos and other data, which is covered in the “Backing Up with GoodSync” video training course in the GreyLearning library. If you’re not a GreyLearning subscriber you can purchase this individual course at a discounted rate using this link:

http://timgrey.me/greysync14

In theory you could also use the “Export as Catalog” command to backup both your Lightroom catalog and your photos in a single process. However, to make this approach useful you would need to export (and therefore copy) your entire catalog of photos. That could obviously require considerable time. Therefore, I only recommend using the “Export as Catalog” feature as a backup option when you need a one-time solution for copying your Lightroom catalog and photos to a different location, or for backing up everything in one overall process. For an ongoing backup solution I recommend something a bit more streamlined, such as the synchronization approach referenced above.