Ask Tim Grey

Today’s Question: Since any image has at least SOME discernible noise, and if the intent is to print large whether on paper or some other medium, why not use noise reduction software all the time?

Tim’s Quick Answer: As long as the noise reduction settings are relatively modest, it is absolutely not a problem to apply noise reduction to all photos. In fact, many software tools for processing raw captures (including those from Adobe) will apply a small amount of noise reduction by default.

More Detail: Every digital photo will exhibit at least a small amount of noise, and so it is reasonable to apply some degree of noise reduction to all images. The key is to make sure the noise reduction settings applied by default aren’t too strong.

I recommend being especially conservative when it comes to luminance noise reduction. For color noise reduction you don’t need to be quite as careful, because it takes rather strong settings for color noise reduction to have a negative impact on a photo.

For example, by default Lightroom Classic applies a small degree of color noise reduction but does not apply luminance noise reduction. I consider this the safest approach in terms of applying noise reduction to all photos.

If settings for luminance noise reduction are too strong, overall texture and detail in the photo can be degraded, sometimes significantly. That is because noise reduction operates in part by averaging out pixel values, and when that relates to tonal values the edge contrast is reduced, leading to a softer appearance for the photo.

With color noise reduction it takes a much more aggressive application before obvious color issues are created. With very strong settings for color noise reduction, for example, you will see a loss of overall saturation and a blending of colors along contrast edges.

But again, as long as your settings for noise reduction are relatively modest (or extremely modest when it comes to luminance noise) I do consider it safe to apply noise reduction to all photos.

Today’s Question: I use Lightroom Mobile to make raw captures on my iPhone, and I sync the captures via Adobe Creative Cloud, from which they are automatically downloaded to my Lightroom Classic catalog on my computer. After this download, I move the images within Lightroom Classic from the Pictures folder on the Mac to an external hard drive, where I keep all of my photos. Can I then delete the photos from my iPhone, or will that cause the photos to be deleted from my external hard drive as well?

Tim’s Quick Answer: Once you have moved photos within Lightroom Classic from the synchronized folder to another storage location (such as an external hard drive) you can safely delete the cloud-based copy of the photos from the Lightroom mobile app without losing the photos on your external hard drive.

More Detail: The Lightroom mobile app includes an option to capture photos in a raw capture format, producing an Adobe DNG (digital negative) file. Those photos are then synchronized to the Adobe Creative Cloud, so they are available through your Creative Cloud account elsewhere, including within Lightroom Classic if you have synchronization enabled.

This provides a convenient way to get the photos captured with the Lightroom mobile app into your normal workflow that revolves around local storage (on an external hard drive in this example).

Once those raw captures have been synchronized to your computer, they will appear in the location designated in Preferences on the Lightroom Sync tab. By default this is within a “Lightroom” folder in the Pictures folder for your operating system. You can drag-and-drop those photos to a different storage location, which will move the source images to the destination location you specify.

However, the photos will remain in your Creative Cloud storage, creating redundancy that can be confusing. Therefore, when you have finished moving the synchronized folders to your preferred local storage location, you can delete the original captures through the Lightroom app on your mobile device. The local copy of those photos managed by Lightroom Classic will not be affected.

Today’s Question: I work exclusively in Lightroom Classic and work on an external drive with nothing on my computer. Backups are critical but when I drag and drop the folder [containing the catalog] to the backup it does not give the option to replace but copies it. The result is the latest folder is inside the prior folder and the process takes 2-3 hours. What am I doing wrong and how do I do it correctly to replace?

Tim’s Quick Answer: I recommend using Lightroom Classic to back up the catalog, I strongly recommend using a synchronization-based backup solution rather than copying files through the operating system, and I recommend discarding older backup copies of the catalog.

More Detail: The built-in catalog backup feature in Lightroom Classic includes options for checking the catalog for errors and optimizing the catalog, which is why I recommend using this backup option even if you are already backing up the catalog with other software.

Rather than depending on an approach that involves using the operating system to manually copy files you want to make an additional backup copy of, I recommend using software that can streamline this workflow. I use GoodSync software (http://timgrey.me/greybackup), for example, to back up my photos and other important files. With this approach only new or updated files are backed up, which can save considerable time. In addition, with this type of approach the backup is an exact match of the original, which is particularly helpful if you ever need to recover from a backup.

Finally, I recommend deleting older copies of your Lightroom Classic catalog backups rather than retaining the clutter and additional storage requirements of numerous backups. When deleting old catalog backups I typically keep the most recent few backups, a backup from several months ago, and perhaps one backup from about six months ago. Keeping older backup copies provides a potential solution in the event that a backup represents a catalog that had already become corrupted, though this is not a very likely scenario.

Today’s Question: Would you comment on the new “enhance” feature in Lightroom [for enhancing detail and enlarging photos]. The description sounds great but the instructions are not very clear.

Tim’s Quick Answer: The new “Enhance” features in Lightroom and Camera Raw include both a “Raw Details” feature for improving the appearance of detail in a raw capture, and a “Super Resolution” feature for enlarging the image to double the linear dimensions (four times the total image area). These features promise to improve the quality of large output for photos.

More Detail: The “Enhance” features make use of Adobe Sensei, which employs artificial intelligence and machine learning to improve the quality of photos, especially for large output.

While my testing has shown that the Raw Details feature does create a visible improvement to the image, that improvement is not dramatic. There is a minor enhancement of edge contrast and smoothness within the photo, which can contribute to a better appearance in a large print.

I’ve been less impressed with the Super Resolution feature. With all of the images I tested the results of Super Resolution did not appear better compared to simple enlargement within Photoshop. In fact, in most cases the Super Resolution version of the image looked worse, with more texture that appeared as noise in what had been smooth areas of the image.

Therefore, I would certainly consider using the Raw Details feature for photos I wanted to print at a large size, but my testing has convinced me that the Super Resolution feature is not providing an advantage in terms of enlargement quality. Hopefully as this feature is improved in the future it will start to provide a clear advantage.

These features can be applied to photos in Lightroom Classic by selecting an image and choosing Photo > Enhance from the menu. In Camera Raw you can right-click on an image in the filmstrip and choose “Enhance” from the popup menu.

You can turn on the “Raw Details” checkbox if you want to enhance details for a raw capture. If you want to enlarge the image, you can turn on the “Super Resolution” checkbox. Note that the Raw Details feature is only available for raw captures (and only those with a Bayer or X-Trans sensor pattern). The Super Resolution feature can also be applied to TIFF and JPEG images.

When you enable Super Resolution, the Raw Details feature will automatically be enabled for supported raw captures.

There is also a “Create Stack” checkbox in the Enhance Preview dialog in Lightroom Classic. I recommend having this checkbox turned on, so that the newly created image will be included in a stack with the original, keeping the images together and making it easier to manage them.

You can then click the Enhance button, and the selected features will be applied to your image.

Today’s Question: For Lightroom Classic, would it be OK to just back up the catalog and not the previews? My previews take forever to back up.

Tim’s Quick Answer: Yes, it is perfectly safe to exclude the previews from a catalog backup for Lightroom Classic. In fact, the built-in backup feature that I recommend using automatically excludes previews from the backup.

More Detail: I strongly recommend backing up your Lightroom Classic catalog to help ensure you are safeguarding the information about your photos. Obviously, you should also be backing up the photos themselves as part of your overall backup workflow.

There is no need to back up the previews that are included in the folder along with the actual Lightroom Classic catalog, because those previews can easily be re-built later should you need to recover from a backup of your catalog.

Even if you are backing up your Lightroom Classic catalog using other software, I still recommend using the built-in backup feature to back up the catalog on a somewhat regular basis. That is because the built-in backup includes options to check the catalog for errors and to optimize the catalog. I recommend making sure both checkboxes for these features are turned on in the dialog that appears when a catalog backup is initiated.

Today’s Question: Can you use the same Lightroom Classic catalog on both an Apple computer and a Windows computer? I’m thinking of switching to a Mac laptop, but am concerned that once I convert to a Mac I’ll never be able to use Lightroom on a Windows desktop again. If you put the files and the catalog on an external hard drive, can you access it from both computers?

Tim’s Quick Answer: Yes, you can use the same Lightroom Catalog on computers running either the Windows or Macintosh operating system.

More Detail: The Lightroom Classic catalog file format is the same for both Windows and Macintosh, so you can switch a catalog between both operating systems without any problems.

The only thing you need to do is make sure the Lightroom Classic catalog is on a hard drive that can be written to by both operating systems. The default file system for hard drives on Windows is NTFS (New Technology File System) and the default for Macintosh is APFS (Apple File System). While it is possible to write to hard drives with either file system on both operating systems, this typically requires special software or drivers.

I recommend simply using a file system that is compatible with both operating systems. More specifically, I recommend using the ExFAT (Extensible File Allocation Table) file system.

If you store your Lightroom Classic catalog as well as your photos on an external hard drive that is formatted with the ExFAT file system, you can switch between working on a Windows or Macintosh computer by simply connecting the external hard drive to the computer and opening the Lightroom Classic catalog from that external hard drive.

Today’s Question: You have talked about moving files from one drive to another within Lightroom Classic. However, let’s say I installed a new drive and want to copy the files to the new one, but want to keep them on the old one as well. How do you do that in Lightroom Classic?

Tim’s Quick Answer: In this case I would use the “Export as Catalog” command to streamline the process of copying photos while still maintaining a link to those photos in the new location.

More Detail: The “Export as Catalog” command in Lightroom Classic enables you to export copies of your photos while creating a new catalog for those photos at the same time. In this case the creation of a new catalog probably isn’t necessary, but it does help ensure that the photos are referenced in the correct location without losing any of the information about your photos.

To get started, open Lightroom Classic and make sure the new drive you want to copy the photos to is connected and available. Then select the “All Photographs” collection in the Catalog section of the left panel in the Library module. From the menu choose Edit > Select None to make sure that no photos are selected. This will ensure you don’t accidentally export only part of the photos.

You can then choose File > Export as Catalog from the menu. Navigate to the location where you want to copy the photos, and specify a name for the overall library of photos, such as “My Photos”. Click the Export button and Lightroom Classic will export copies of all photos with the same folder structure as they were contained in on the source drive, with a new catalog created within that folder as well.

You can then launch the catalog from the new location by double-clicking on the file with the “.lrcat” filename extension. If you prefer you can also move the folder containing the catalog that was created as part of this export process to a different location, such as to your internal hard drive.

Today’s Question: In your GreyLearning Series on Optimizing Photos, in the lesson on HDR images you had a series of six captures ranging from a dark exposure to a light one. The sun was in the frame. My question is how did you make six captures with different settings without the sun moving, or apparently moving?

Tim’s Quick Answer: The key when including the sun (or moon) in the frame when capturing a series of exposures for a high dynamic range (HDR) result is to capture those exposures quickly using automatic exposure bracketing (AEB).

More Detail: While the sun and moon don’t seem to be moving all that fast across the sky to the unaided eye, they are certainly moving. In the case of the sun the rate of movement is about fifteen degrees per hour. That still isn’t incredibly fast movement across the sky, but it does create a risk that if you capture bracketed exposures that include the sun or moon, there could be a change in position for the sun or moon from one frame to the next.

Automatic exposure bracketing enables you to capture the various exposures as quickly as possible, minimizing the risk of movement between frames.

The specifics of how you employ automatic exposure bracketing will vary from one camera to the next, and not all cameras support this feature. In general, you will enable the bracketing via menu settings, where you can set the number of exposures to bracket and the number of stops between exposures. Two stops of separation between exposures works well for HDR bracketing.

With many cameras in addition to configuring the bracketing settings you’ll need to use a timer for the bracketing to be completely automatic. For example, you might set a 3-second timer so that when you trigger the exposure the bracketed captures will all be taken in rapid succession.

And, of course, to some extent HDR software can manage minor variations from one frame to the next.

For those interested, the HDR image in question was a sunrise photo of an abandoned homestead farmhouse in the Palouse region of eastern Washington State. You can see the photo on my Instagram feed here:

https://www.instagram.com/p/36alRoJ-fH/