Calculating Effective Focal Length


Today’s Question: Imagine you are using a 100mm lens on a full frame camera body. This combination makes images that are 3000×2000 pixels. When you crop the image to be 1500×1000 pixels what is the “implied” focal length of the lens. How is this computed?

Tim’s Quick Answer: You can calculate effective focal length in this type of situation by calculating the ratio represented by the starting and ending dimensions, and then multiplying that value by the focal length used to capture the original image to determine the effective focal length for the field of view of the cropped image.

More Detail: Calculating the effective focal length for an image you’ve cropped can be helpful in terms of knowing what lens focal length would have been required to achieve the field of view of the cropped image, for example.

To calculate the ratio represented by the crop, you can divide the pixel dimensions for the original image by the pixel dimensions for the cropped image, being sure to use the pixel count for the same side (such as calculating for only the width or only the height) for both images.

With the example above, you could divide the original width (3,000 pixels) by the cropped width (1,500 pixels) to calculate the ratio of 2 (3000 / 1500 = 2). This ratio represents the crop factor. Since the original image was captured with a lens focal length of 100mm, you could multiply that focal length by the ratio you determined, which in this example gives an effective focal length of 200mm (100 X 2 = 200).

So, with the example outlined above, to achieve the same field of view from the cropped image in an original capture you would need to use a 200mm lens rather than a 100mm lens.

Saved Adjustments for Custom Mask


Today’s Question: I frequently apply a similar set of adjustments to the background of a photo such as reducing the sharpness and color saturation. Is there a way to create a preset in Lightroom Classic that I can apply only to the currently masked area in a photo?

Tim’s Quick Answer: Yes, you can apply a set of saved adjustments to the current mask by using a preset with the masking feature rather than by creating a Develop preset.

More Detail: When you create a new Develop preset in Lightroom Classic any targeted adjustments you applied to the image used as the basis of the preset can be included. That means the actual mask will be saved as a part of the preset.

If you used one of the fully automatic mask options, such as Sky or Background, then this will work perfectly fine, because when you apply that preset to another image the effect will be adapted to the image. So, if you created a preset that includes a targeted adjustment based on an automatic Sky mask, when you apply that to another image the sky will be detected in that image, rather than using the shape of the mask from the image the preset was based on.

However, in some cases you may want to use a set of adjustments to apply changes to an image based on a custom mask you’ve created yourself. For that you’ll want to use a preset with the masking feature rather than for the overall Develop module.

To get started, you can apply a targeted adjustment to an image using the masking feature, and configuring the adjustments based on how you want to save them for the preset. When you’re finished, go to the top of the adjustments for the masking feature on the right panel and click the Preset popup. Choose “Save Current Settings as New Preset” from that popup and enter a meaningful name in the Preset Name field in the New Preset dialog that appears.

Anytime you’re working on an image and you want to apply the saved preset to a specific area, create a mask for the area, and then choose the preset you created from the Preset popup. The adjustment settings from your saved preset will be applied to the area defined by the current mask.

Preventing the Loss of Collections


Today’s Question: I knew about flag status not getting saved in the XMP files, so I periodically mark all my flagged photos with one star. However, I never thought about collections, which I use extensively. Are there any strategies you recommend to safe-guard collections?

Tim’s Quick Answer: I recommend using keywords to identify the collections that photos belong to, so that you can recreate collections easily even if your Lightroom Classic catalog is lost or becomes corrupted.

More Detail: As noted in Tuesday’s (May 7th) Ask Tim Grey eNewsletter, collections only exist within the Lightroom Classic catalog. Therefore, if you lost your catalog and weren’t able to recover from a catalog backup, when you recovered by creating a new catalog you would no longer have the catalogs you had previously created.

This situation can obviously be avoided by making sure you use a good backup workflow to ensure you won’t ever need to create a new empty catalog. But you can also safeguard collections beyond the Lightroom Classic catalog by using keywords to identify the collections that photos belong to.

This is a concept that I playfully refer to as “fake keywords”. The keywords are very much as real as any other keywords, but they are used in a way that is different from the “normal” way keywords are used. I use this type of keyword to identify the status of photos, such as to indicate those I’ve shared to my Instagram feed or photos I’m including in a photo project such as a book.

In this case, for example, you might use a keyword structure of something like “Collection-Calendar 2025” to indicate that the photos with this keyword belong to a collection called “Calendar 2025”. You can assign the keyword to all photos that you’ve added to the “Calendar 2025” collection, and then of course you’ll want to make sure the metadata is saved to the source files on your hard drive so the information will be preserved beyond the Lightroom Classic catalog.

You can select photos and manually save metadata to the files by going to the menu and choosing Metadata > Save Metatata to Files. However, I recommend enabling the option to automatically save metadata to your photos. This can be enabled by turning on the “Automatically write changes into XMP” checkbox on the Metadata tab of the Catalog Settings dialog in Lightroom Classic.

Keep in mind that when you save metadata to the source files in Lightroom Classic, not all information you’ve assigned in Lightroom Classic will be preserved. Metadata such as pick and reject flags, membership in collections, virtual copies, and history states in the Develop module are only saved to the catalog. That’s why when some of this information is important to you, it is a good idea to record the information in a standard metadata field (such as Keywords) that can be saved to the source image files.

Reset All Adjustments in Camera Raw


Today’s Question: Is there a way to reset all sliders [in Camera Raw] at one time?

Tim’s Quick Answer: Yes, in Camera Raw you can click on the “More” button and choose “Reset to Default” to reset all adjustments to their default values.

More Detail: If you want to reset the adjustments in Camera Raw to the default settings, you can use the “Reset to Defaults” command. This is found on the “More” button, which is a button showing an ellipsis (three dots) on the toolbar at the top-right of the Camera Raw interface.

If you open a raw capture that has never been modified with Camera Raw, then you can also use the Reset button to reset all adjustments to their default values. To do so simply hold the Alt key on Windows or the Option key on Macintosh. That will cause the Cancel button to change to a Reset button, and you can click that button while holding the Alt/Option key to reset all sliders to their defaults.

However, if you re-open a raw capture you had previously modified with Camera Raw, the standard Reset button won’t work. That’s because the Reset button actually resets all adjustments to what they were set to when you opened the image, not to the Camera Raw defaults.

For example, let’s assume you processed a raw capture to a black and white interpretation using Camera Raw. The adjustment settings will be preserved with the source image (in an XMP sidecar file in the case of a proprietary raw capture).

If you open that raw capture again in Camera Raw, it will appear in black and white based on the previous adjustments. If you hold the Alt/Option key and click the Reset button, you’ll only reset adjustments modified since you just opened the image, meaning you’ll be resetting to the black and white version in this example.

If on the other hand you click the “More” button and choose “Reset to Default”, you’ll be resetting all adjustments to the Camera Raw default settings, which in this example means you would be resetting the black and white image back to the original color capture.

Mixing Lightroom and Lightroom Classic


Today’s Question: With all the buzz about Lightroom (Lr) since it now has a local storage option, I am of course intrigued, although I’m not ready to abandon Lightroom Classic (LrC). I dabbled with Lr on some images already imported into my LrC catalog, but the edits I made with Lr did not appear to be reflected when then I accessed those same images with LrC (I use mostly dng for my raw images and have the “Automatically write changes into XMP” turned on). This begs the question: where are the edits made with Lr stored?

Tim’s Quick Answer: The cloud-focused version of Lightroom stores local metadata updates (including adjustments) in the source file since there isn’t a catalog. In the context of images being managed in Lightroom Classic, that means updates from Lightroom will result in a metadata mismatch in Lightroom Classic.

More Detail: By default, Lightroom Classic stores all metadata updates exclusively in the catalog. If you turn on the “Automatically write changes to XMP” checkbox on the Metadata tab of the Catalog Settings dialog, standard metadata fields as well as Develop adjustments will be saved to the source image file. For proprietary raw captures that means the updates will be saved to an XMP sidecar file so that the raw capture is not modified.

Lightroom (the cloud-focused version) saves metadata updates for local photos (those found via the Local tab) directly in the source image file, which again means an XMP sidecar file for proprietary raw captures.

If you make an update in Lightroom Classic and save metadata updates to the source file, those updates will be reflected in Lightroom (though in my experience it is often necessary to restart Lightroom to actually see the changes).

If you make an update in Lightroom, you won’t initially see the update reflected in Lightroom Classic. Instead, you’ll see an indication of a metadata mismatch, such as by having an icon showing three lines and an upward-pointing arrow at the top-right of the thumbnail for the image. Similarly, the Metadata Status field on the Metadata section of the right panel in the Library module would show “Changed on disk”.

If you want to bring the updates from Lightroom into Lightroom Classic, you would need to click the icon indicating the metadata mismatch (or the button at the right of the Metadata Status field) and choose the option to “Import Settings from Disk”. This would overwrite the settings in the Lightroom Classic catalog with the metadata updates from the file that had been written from Lightroom.

Needless to say, with this situation there is considerable risk of confusion about where the latest updates actually reside, and which updates you actually intended to be the final updates. This is one of the reasons I don’t recommend using a workflow that combines both Lightroom and Lightroom Classic.

If you’re using Lightroom you can certainly use other software such as Adobe Bridge to browse and manage your photos. However, if you’re using Lightroom Classic I don’t recommend using any software outside of Lightroom Classic to manage your photos, and only use third-party tools to edit your photos if you initiate the process from within Lightroom Classic.

Collections from Corrupted Catalog


Today’s Question: I have a corrupted catalog and have created a new one. I was able to import all my photos (over 200,000) successfully. However, I can’t export/import any of my collections from the old catalog. Is there a way to copy them to the new catalog?

Tim’s Quick Answer: Collections are only contained within the Lightroom Classic catalog, not in the metadata for individual photos. Therefore, the only way to transfer collections into a new catalog is to import from the prior catalog, if that is possible in view of the older catalog being corrupted.

More Detail: By default, Lightroom Classic only stores metadata updates in the catalog, not in the metadata for the source image files. You can save standard metadata to the source images, such as by turning on the “Automatically write changes into XMP” checkbox on the Metadata tab of the Catalog Settings dialog.

However, saving metadata to the source files will only preserve standard metadata fields in the source file, not special features of the Lightroom Classic catalog such as collections. Similarly, by the way, features such as pick and reject flags, virtual copies, and the history in the Develop module are only saved to the catalog, even when you save metadata to the source image files.

Therefore, the only way to get catalog-only features such as collections into a new catalog is to import that information from the prior catalog. When the reason for creating a new catalog in the first place is a corrupted catalog, this can obviously be problematic.

That said, it is still worth a try. I would start by creating a new empty catalog, which you can do by choosing File > New Catalog from the menu. Once you’ve created and opened that new catalog, you can try to import from the prior catalog that appears to be corrupted. To do so, choose File > Import from Another Catalog from the menu. In the dialog that appears navigate to the location of the prior catalog, select the file with the “.lrcat” filename extension, and click the Choose button.

If this approach is successful, you will have the information about your photos, including collections, imported into the new catalog from the prior catalog, and you should be in good shape. If that doesn’t work due to the catalog being corrupted, the only other option would be to recover from an earlier backup of the catalog.

Flagging Photos as Priority


Today’s Question: I shoot sports photography for local Parks & Rec baseball teams. My grandson plays on one of the teams and I want to give priority to processing his images first. I can’t determine if it is better to store his images in a separate folder when shooting the event, or to flag his images in Lightroom Classic after import so they can be processed first.

Tim’s Quick Answer: In this type of situation, it is probably faster and easier to flag the photos after capture rather than trying to do so during the event. In Lightroom Classic one great option is the Painter for applying metadata quickly to photos.

More Detail: Depending on your camera, it may be possible to flag photos in some way during the process of capturing images. For example, many cameras enable you to assign star ratings to photos as part of the process of reviewing the photos on the camera’s LCD display, and you could mark the applicable photos with a one-star rating to help identify them, for example. However, this would likely be a challenging workflow in the context of capturing a relatively large number of photos in a relatively short period of time.

I therefore recommend flagging the photos after the capture as a more efficient approach. In Lightroom Classic I think the Painter tool is a great way to approach this.

To get started I would import all photos from the game into the same folder. You can then browse all those photos in the grid view display. On the toolbar below the image preview area, you can click the Painter tool, which has an icon showing a can of spray paint. To the right of where the Painter tool icon appeared (which will now be a circle where you can drop the Painter tool when you’re done) you can select a metadata option from the popup. For example, you could choose “Label” from the popup to use a color label to flag the photos, selecting the desired color label from the set of options to the right of the popup.

Once you’ve configured the Painter for the metadata you want to use to flag the photos, you can click on thumbnails to mark them with the metadata attribute. In addition to being able to click on a single photo to mark it, you can click-and-drag across multiple thumbnails to mark a series of images. This can make it very efficient to mark multiple photos as you scroll through the thumbnails.

When you’re finished with the Painter tool you can click the Done button on the right side of the toolbar below the image preview area. You can then set a filter based on the metadata field you used to mark the photo, so you can view only the images you want to prioritize for editing.

Lightroom Classic on Windows and Macintosh


Today’s Question: I am doing as I saw you suggested [putting the catalog on an external hard drive] to be able to use Lightroom Classic on both my Mac and PC. I formatted my drives in exFAT and they are read fine by both computers. My problem is that for some reason Lightroom Classic is not able to find most of my photos. If I locate them and restart, they are found, but the next time I use Lightroom they are again lost. What do you think I am doing wrong?

Tim’s Quick Answer: This issue is caused by the fact that Windows and Macintosh use a different approach to managing the path to folders and photos. In this scenario I recommend using a top-level folder for photo storage so you only need to reconnect that single folder when you switch platforms.

More Detail: The Lightroom Classic catalog is cross-compatible with both Windows and Macintosh, meaning you can open the same catalog on computers running either Windows or Macintosh (though you can still only open the catalog on one computer at a time).

The first step is to make sure the external hard drive you’ll use to store the catalog is formatted with a file system that is compatible with both Windows and Macintosh. For example, you can format the drive with the exFAT file system, but keep in mind that formatting a drive will completely erase the contents, so you’ll want to perform this step before you have put any data on the drive.

I then recommend creating a top-level folder on the drive for storing your photos. For example, you could create a “My Photos” folder on the external drive, and then create subfolders that will contain your photos within that top-level folder. Photos contained within that top-level folder can then be fully managed within your workflow using Lightroom Classic.

When you switch platforms, all folders and photos will appear missing initially. That’s because Windows is using a drive letter to track the hard drive, and Macintosh is using a volume label. After switching platforms and opening the catalog, you can then right-click on your top-level folder in the Folders list on the left panel in the Library module and choose “Find Missing Folder” from the popup menu. Navigate to that folder on the external hard drive and click the Choose button, and all folders and photos will be reconnected, so they are no longer missing.

I also recommend assigning a specific drive letter to the external hard drive on Windows using the Disk Management feature, so that when the drive is connected it will always be assigned the same drive letter.

You will need to use the “Find Missing Folder” feature each time you open the catalog on a different operating system, assuming you had reconnected the folders and photos the previous time you were using the catalog on a different operating system. But it is possible to work with the same Lightroom Classic catalog on both Windows and Macintosh, as long as you don’t mind reconnecting the top-level folder each time.

Mirrorless Camera Shutter Count


Today’s Question: I’m considering trading in one of my Nikon mirrorless cameras (Z6II) and I know the first thing they’ll ask me about is what the shutter count is. With my Nikon DSLR cameras, I was able to take a photo and look at the EXIF data to find the shutter count information. But I can’t find a Shutter Count field for my mirrorless camera. Do mirrorless cameras not have that field? How do you find the information?

Tim’s Quick Answer: Most mirrorless (and DSLR) cameras do track the number of shutter actuations, but that information isn’t always displayed in typical photo-management software. However, there are other resources that can help you get this information.

More Detail: First off, since today’s question related to shutter actuations on a mirrorless camera, I wanted to point out that this topic is referring only to actuations of the mechanical shutter. If you use the electronic shutter rather than the mechanical shutter, then you obviously aren’t adding wear to the mechanical shutter. Most cameras are rated for the shutter to last for about 100,000 to 400,000 actuations. That’s not to say the shutter will fail right as you reach that number, but it provides a sense of the degree to which you should be concerned about a possible failure.

With many cameras you can use software provided by your camera manufacturer to find out how many times the shutter has been actuated. For example, the EOS Utility software from Canon enables you to check this information for Canon cameras. With other cameras also include an option to check the camera directly on the menu system for the camera to determine the total number of shutter actuations.

If your camera model doesn’t provide an easy way to determine the number of shutter actuations, in many cases you can use the Camera Shutter Count website to determine this information. Simply upload an original capture from your camera (not an edited image) to the website, and the number of shutter actuations will be shown. Note that small text on the website lists the camera models that are supported.

You can find the Camera Shutter Count website here:

Delay Saving Metadata to XMP


Today’s Question: When I have been working on a number of photos in Lightroom Classic and close the program, I often get a message that it has not finished updating Metadata. However, sometimes I see this message when I haven’t done much work on photos, and I think Lightroom should have easily completed the Metadata updates. What do you suggest?

Tim’s Quick Answer: This is an example of a situation where I recommend turning on the “Don’t show again” checkbox in the alert dialog, so you won’t have to see this unnecessary alert when quitting Lightroom Classic.

More Detail: When you turn on the “Automatically write changes into XMP” checkbox on the Metadata tab of the Catalog Settings dialog in Lightroom Classic, updates to standard metadata fields will be saved to the source image file in addition to being saved in the catalog. This won’t include all information included in the catalog, but it does provide a good way to back up standard metadata fields beyond the catalog.

If Lightroom Classic is still working on saving metadata to the source images when you quit, you’ll see a dialog alerting you to that fact. As noted in the dialog, however, if you choose to quit then Lightroom Classic will resume updating metadata to the files the next time you launch the software. So, there’s really no need to be concerned about this issue at all.

You can simply turn on the “Don’t show again” checkbox in the alert dialog so you won’t see the message in the future. Lightroom Classic will still continue updating metadata in the background, resuming the process if you quit before it was finished.

If at any time you want to make sure that metadata updates have been saved for some (or all) your photos, you can use the option to manually save metadata. Start by selecting the folder that contains the images you want to update. You can even choose the “All Photographs” collection in the Catalog section at the top of the left panel in the library module to browse all photos in your entire catalog.

Next, select all the photos you want to update, such as by choosing Edit > Select All from the menu. Then choose Metadata > Save Metadata to Files from the menu. At this point you’ll see a progress bar on the identity plate at the left end of the top panel, showing the progress of saving the metadata. That means you’ll have an indication of when the update has finished, so you can be confident that the selected photos had standard metadata values updated based on the updates already saved in the catalog.