XMP Option for Adobe DNG Files


Today’s Question: I understand the benefits of enabling XMP sidecar files for proprietary raw captures in Lightroom Classic, but what about for Adobe DNG files?

Tim’s Quick Answer: The same benefits of enabling XMP sidecar files for proprietary raw captures in Lightroom Classic apply to Adobe DNG and other supported image formats. The only difference is that for files other than proprietary raw captures the metadata updates are written directly to the source files rather than to an XMP sidecar file.

More Detail: As I’ve addressed previously in the Ask Tim Grey eNewsletter, I strongly recommend turning on the “Automatically write changes into XMP” checkbox on the Metadata tab of the Catalog Settings dialog in Lightroom Classic.

The checkbox is a little misleading, however, because when you enable this option XMP sidecar files are only created or updated for proprietary raw captures. For other supported image file types, including Adobe DNG (Digital Negative) images, the metadata updates will be written directly to the source image file.

It is important to remember that these metadata updates are limited to standard metadata fields as well as the actual adjustments applied in the Develop module. With this option enabled you can view standard metadata updates in other software such as Adobe Bridge, but you should not make any changes to metadata outside of Lightroom Classic.

Perhaps more important is to keep in mind that Lightroom-specific updates that are not included in an existing metadata standard will not be preserved in this way and will only be included in the Lightroom Classic catalog. That includes, for example, collections, virtual copies, Pick and Reject flags, and the history in the Develop module.

Primarily because it provides a backup for what is generally the most important metadata updates in your Lightroom Classic catalog, I strongly recommend turning on the “Automatically write changes into XMP” checkbox. You can read more about how important this is in the context of losing information from your catalog on the Ask Tim Grey blog here:


Smart Preview Shortcomings


Today’s Question: Are there any limitations or downsides to editing a Smart Preview in Lightroom Classic? I am thinking in particular of brush mask edge resolution differences that might exist between a mask created within a Smart Preview versus the full resolution original image file, especially with the “Auto Mask” checkbox turned on.

Tim’s Quick Answer: The negative consequences of using Smart Previews in the Develop module within Lightroom Classic are very minor, and mostly relate to the fact that the overall image quality for the Smart Preview will not match the higher quality of the original image.

More Detail: Today’s question is a follow-up to my answer in the May 10th Ask Tim Grey eNewsletter regarding Smart Previews in Lightroom Classic. If you’d like to review the original question and answer, you can find them on the blog here:


In short, in Lightroom Classic you can build Smart Previews for photos, which enable you to perform various tasks with your photos even when the source image files are not available. That means an external hard drive that contains your photos could be disconnected, but you could still work in the Develop module or export reduced-resolution copies of the photos based on the Smart Previews. There’s also an option in Preferences to prioritize the use of Smart Previews in the Develop module even when the source photos are available, in order to improve performance.

The primary disadvantage to working with Smart Previews is that those previews are a reduced-resolution version of the original image. Therefore, you aren’t seeing a top-quality preview for the photo as you’re making decisions about the adjustments you apply.

This is a very minor issue that really won’t have a significant impact on the final image quality, since the adjustments applied based on the Smart Preview will synchronize with the source image as soon as it is available again. So while in principle I prefer not to use Smart Previews in the Develop module, the negative consequences of doing so are very minor.

This holds true if you are applying targeted adjustments with the masking features, even if you are making use of the “Auto Mask” option for the Brush feature. The masks you create based on the Smart Preview will still be very accurate, and those masks will be scaled for the full-resolution image when the updates are synchronized.

Therefore, if you feel there is an advantage being able to use Smart Previews in the Develop module, then I would not try to discourage you from doing so. If you don’t need Smart Previews in your workflow then I wouldn’t suggest generating them, but the downside to using them is absolutely minimal.

Renaming Photos in the Camera


Today’s Question: In response to your answer about avoiding duplicate filenames when importing photos into Lightroom Classic, is it possible to rename photos in the camera to help ensure unique filenames when shooting with more than one camera?

Tim’s Quick Answer: Yes, with some cameras you can change the default naming structure. Most will still only allow you to use four digits for the sequence number for photos, but using a unique prefix with each camera can help avoid most common issues related to duplicate filenames.

More Detail: Most cameras only allow you to use four digits for the numeric sequence number, because this is part of the “Design rule for Camera File system” (DCF) specification. Some cameras allow for a five-digit sequence number, but this is not within the DCF standards used by most cameras.

With only four numbers available for the sequence number portion of the filename, you’ll only be able to capture 9,999 photos before the camera rests to image number 1 again. Therefore, many photographers prefer to rename photos as part of their organizational workflow to have greater flexibility with the filename structure.

However, when it comes to capturing photos with two different cameras, there is obviously the risk that each of the two cameras used on a single photo outing may result in filename duplication. For example, both cameras may capture an image with a filename such as “IMG_1234.cr2”.

In a previous answer I explained how it was possible to use a renaming template in Lightroom Classic to rename photos, including the option to make filenames unique based on the camera used. On option, for example, would be to use the camera serial number as part of the file renaming structure.

However, with many cameras it is also possible to change the structure for the file naming in the camera, so that each of your camera bodies could have a unique filename structure. For example, if you had two Nikon cameras you might change the structure to something like “NC1_1234.nef” for the first camera and “NC2_1234.nef” for the second camera. This would ensure unique filenames across two (or more) cameras, although obviously you could still end up with duplicate filenames from the same camera when you roll over from 9,999 to 0001 for the sequence number.

Accurate Display Color


Today’s Question: Do you have some information as to how to adjust your screen on the computer to the correct color temperature? I remember years ago there was a lot of emphasis on this. What should we use? If you work for the internet, everyone’s computer screen is different. What color profile would you use?

Tim’s Quick Answer: I strongly recommend calibrating your display using a colorimeter device. I personally use the Calibrite ColorChecker Display (https://bhpho.to/3wi7Aen) for this purpose. When preparing images to share online, I recommend using the sRGB color space to help ensure better accuracy with uncalibrated displays.

More Detail: As a photographer you should absolutely calibrate your monitor display to ensure the colors you see are an accurate reflection of the colors in your images, so that the adjustments you apply will be based on an accurate view of the image. I use the Calibrite ColorChecker Display (https://bhpho.to/3wi7Aen), which was formerly branded as X-Rite Photo. Another excellent option is the Datacolor SpyderX Pro (https://bhpho.to/3ylFSjP).

Calibrating your display will ensure that images look correct for you, but of course many people who may view your images online are not calibrating their displays. I still recommend optimizing photos based on an accurate calibrated display, recognizing that the photos may not appear completely accurate for users who have not calibrated.

To help ensure accurate color for images shared online even among non-calibrated displays, I recommend using the sRGB color space. That is because the sRGB color space was created to encapsulate the colors of a typical monitor display. Therefore, sRGB pixel values will generally appear relatively accurate even on a non-calibrated display.

In addition to ensuring accurate color, calibrating a display will help ensure optimal brightness levels. I consider this quite important as well considering that most displays with a default configuration will be about a full stop too bright, meaning twice as bright as they should be. Solving for this issue on your display won’t guarantee that all viewers will see an accurate view of your photos, but it will help.

Traveling with the Master Catalog


Today’s Question: I use a laptop as my only computer. When traveling I use Lightroom Classic to import photos and make primary and second copy using two external hard drives drives. How do I best make the transfer from travel hard drives to my larger hard drive at home? I don’t think I should need a second travel catalog.

Tim’s Quick Answer: In this scenario you most certainly do not need to use a separate catalog when traveling. Rather, you can simply import photos into your master catalog on your laptop, and then move the photos to your primary hard drive using Lightroom Classic when you get home.

More Detail: Because you (like me) use a laptop as your only computer, you can always have your master Lightroom Classic catalog available whether you’re at home or traveling. Therefore, there is absolutely no need to use a separate catalog when traveling. You can simply import new photos into your master Lightroom Classic catalog while traveling.

If you’re not going to be traveling with your large hard drive that is used for primary storage at home, obviously you’ll need to copy the photos you import while traveling to a different storage location. That could be on the internal hard drive of your laptop if you have enough storage capacity, or to an external hard drive as you are currently doing.

When you return home and your primary storage drive is available, you can then move the photos from the temporary storage location you were using during the trip to the primary hard drive. Just be sure to do this within Lightroom Classic.

When you have imported photos to more than one hard drive in Lightroom Classic you’ll see a header for each of the hard drives in the Folders list on the left panel in the Library module. With both hard drives connected to the computer you could then drag the folder from the traveling hard drive that contains the new photos to the top-level folder for your photos on your primary hard drive at home.

Note that if your folder structure is contained on the root level of the hard drive, you likely won’t have the root level available to drag the folder to. Instead, you’ll need to reveal the parent folder, which in this example would be the hard drive itself. To reveal that root level simply right-click on a top-level folder on the hard drive and choose “Show Parent Folder” from the popup menu. This will reveal a folder representing the level above the existing folders, and you can drag your traveling folder to that top level. If you want to then hide the parent folder again you can right-click on it and choose “Hide This Parent” from the popup.

Update Process Version in Batch


Today’s Question: I have many photos in Lightroom Classic still set to Process Version 3. How can I update them all to Process Version 5 in one step?

Tim’s Quick Answer: You can update the Process Version for all photos by selecting all photos in the catalog, making sure a photo with an older Process Version is the active photo, and then changing the Process Version in the Develop module while the Auto Sync feature is enabled.

More Detail: You can think of the Process Version in Lightroom Classic as relating to the version of Lightroom Classic that was used to process a photo in the Develop module. The Process Version determines which adjustments are available and how they work, based on updates to the Process Version over the years.

For example, I’m sure many Lightroom Classic users are familiar with the current set of tonal adjustments in the Basic section of the right panel in the Develop module. Those are Exposure, Contrast, Highlights, Shadows, Whites, and Blacks, which are reflected in the most recent Process Version 5. However, in the first Process Version those adjustments were Exposure, Recovery, Fill Light, Blacks, Brightness, and Contrast.

In addition to different adjustments being available in different process versions, the algorithms behind some adjustments have changed over the years as well. In general, I recommend working with photos in the most recent Process Version, which is current Process Version 5.

If you want to update the Process Version for all images in the catalog, you will want to first locate an image that has the Process Version set to something other than Process Version 5. The setting for the Process Version is the Process popup found in the Calibration section at the bottom of the right panel in the Develop module. It is important that an image with an older Process Version be the active photo, as otherwise selecting the latest Process Version from the popup won’t actually register as a change.

After selecting an image that has an older Process Version set, choose the “All Photographs” collection in the Catalog section of the left panel in the Library module. Make sure there aren’t any filters set on the Library Filter bar so you’re seeing all your photos. Then choose Edit > Select All to select all photos in your entire catalog.

You can then go to the Develop module and click the toggle switch on the left side of the Sync button at the bottom of the right panel, which will enable the Auto Sync feature. Then go to the Calibration section and choose “Version 5 (Current)” from the Process popup.

Keep in mind that there is the possibility that the appearance of some photos will change slightly when you update the Process Version. For this reason, some photographers prefer to update the Process Version only for individual photos as you work with them, rather than in batch. However, you can certainly update the Process Version in batch as explained here. I do recommend however that you then review images that you intend to print or otherwise share to fine-tune the adjustments in the Develop module as needed, in case the update to the Process Version caused an undesirable change to the appearance of the photo.

Evaluating Lens Sharpness


Today’s Question: I’m trying to evaluate the sharpness of several lenses, but I don’t know how much I should be able magnify an image and still have very sharp edges. In other words, I can look at an image using the “fit” setting in the Navigator in Lightroom Classic and the image looks good. But if I enlarge it to, say, 200%, it looks soft. Is that normal when enlarging an image that much, or is that because the lens is not very sharp? At what magnification should I view an image to critically judge the sharpness of an image/lens?

Tim’s Quick Answer: I recommend using a 100% zoom setting when evaluating sharpness for a photo. However, to test the sharpness of a lens I recommend photographing a lens resolution test chart rather than evaluating standard photos.

More Detail: The reason a 100% zoom setting is preferred when evaluating the sharpness of an image is that at 100% one pixel in the image is represented by one pixel on the monitor display. The reason the image appears softer at a higher zoom setting is that multiple pixels on the display are being used to display each pixel in the image, and so there is blending introduced along the contrast edges in the image.

When evaluating lens sharpness, you could simply use a relative comparison between test images captured by different lenses. In other words, you would simply be determining which lens was sharper than another, without actually quantifying the results.

If you want to get more detailed in your evaluation, you can use a lens resolution chart. However, a calibrated lens resolution chart can be rather expensive, ranging from several hundred dollars to more than one thousand dollars (https://bhpho.to/3KDurGL).

There are some less expensive (though less precise) options that can work well. For example, the DGK Color Tools test chart (https://bhpho.to/3kBb2LK) sells for about $16. You can also use printed text as a reasonable alternative in place of a test chart, comparing the sharpness of the edges of text from one photo to the next.

By using a single lens chart or other target for each lens you’ll test you can get more accurate and meaningful results. And if you want to be particularly detailed in your evaluation you can use a lens resolution chart that enables you to measure the actual effective resolution of a lens (generally represented by a number of line pairs per millimeter in a test target).

Download Before Import


Today’s Question: When would you download photos with Adobe Bridge before importing into Lightroom Classic?

Tim’s Quick Answer: The only time I would download photos with Adobe Bridge before importing photos into Lightroom Classic would be when importing photos from a mobile device such as a smartphone. Otherwise, I always download as part of the process of importing photos into Lightroom Classic.

More Detail: I strongly recommend making full use of the import feature in Lightroom Classic, including downloading photos from a media card to their final destination as part of that process. This helps to streamline the import workflow and avoid the confusion that can occur when you download photos before importing them into the catalog.

However, with smartphones and other mobile devices I generally download photos first and then import them into Lightroom Classic. That is because with some mobile devices (especially iPhones and iPads) it can be challenging to delete photos after having downloaded them.

Therefore, I use a workflow that involves downloading photos from my mobile device to a temporary storage location using Adobe Bridge. I then import the photos into my Lightroom Classic catalog, copying them to the intended final destination. At that point I will confirm the deletion of photos from my mobile device in Adobe Bridge.

This workflow is covered in the lesson on importing photos that is included in my “Lightroom Lectures” course, which is included in the GreyLearning Ultimate Bundle. If you’re not already an Ultimate Bundle subscriber, you can sign up with a 33% discount by following this link to get started:


Editing Smart Previews Outside Lightroom Classic


Today’s Question: I built Smart Previews for some images in Lightroom Classic so I could work with them without having my external hard drive connected. I am able to edit the images in the Develop module, but the option to use any external editor (including Photoshop) is greyed out. I was under the impression that smart previews allow for all editing, but is it just limited to editing in Lightroom Classic only?

Tim’s Quick Answer: Smart Previews in Lightroom Classic enable you to edit photos in the Develop module (or export a lower resolution copy of the image) even if the source image is not available, such as when an external hard drive is disconnected. However, you are not able to send a smart preview from Lightroom Classic to an external editor, as the original image is required for that purpose.

More Detail: When you built a Smart Preview for a photo an Adobe DNG (Digital Negative) file is created at a reduced resolution of about 2500 pixels on the long side. The Smart Previews are stored alongside the catalog, so that they can be accessed even if the source image files are not available, such as if you have disconnected the external hard drive containing the source images.

Smart Previews can be used in place of the original image in the Develop module within Lightroom Classic, so you can apply adjustments even without the source image. When the source image is available again the adjustment updates will be synchronized to the original automatically.

You can also export copies of images based on Smart Previews, though in general I recommend exporting based on the original file instead. Among other things, the Smart Preview will generally be of a lower resolution than the original.

However, you are not able to send a Smart Preview to an external editor from Lightroom Classic using the Photo > Edit In option on the menu. That is because these options require a derivative image (such as a TIFF or PSD file in the case of Photoshop) based on the original image file. You therefore need to make sure the source image file is available when you want to use an external editor.

Avoiding Duplicate Filenames


Today’s Question: I now own two different Canon camera bodies. How do I import photos into Lightroom Classic from my second camera body that might have the same image numbers? I don’t change file names.

Tim’s Quick Answer: Lightroom Classic will automatically append a number (such as “-2”) to a filename that is copied into the same folder as a file with the same name. However, you could also rename photos upon import to avoid this variability in file naming.

More Detail: It is not possible to have two files with the exact same filename in the same folder. In general, software or the operating system will ask how you want to deal with this issue, such as by replacing the existing file or using a unique name. In the case of Lightroom Classic this issue is handled automatically when importing photos.

Of course, if the photos were exact duplicates, then having the “Don’t Import Suspected Duplicates” checkbox turned on in the Import dialog would prevent those duplicates from being imported a second time. In this case, however, the photos aren’t duplicates, they just have the same filename. Therefore, Lightroom Classic would still copy the files, but will append a number to the filename so that the names are unique.

This could lead to variability in your filenames, such as having one file named IMG_1234.cr2 and another file that had the same name being renamed to IMG_1234-2.cr2. If you would prefer to avoid this variability and the potential confusion of filenames that are nearly the same, you could rename your photos with a different format.

You could, for example, add the camera serial number to the filename structure, perhaps using the serial number as the first part of the filename and the existing filename as the second part. Or you could use a completely different structure altogether. That renaming can be done as part of the import process in the File Renaming section on the right panel. You could also rename the photos later in your workflow within Lightroom Classic by selecting the images within the Library module and choosing Library > Rename Photos from the menu.