Ask Tim Grey

Today’s Question: The term “fast glass” was common decades before autofocus lenses came on the market. Fast glass allowed faster shutter speeds for use in sports photography, to better stop the action of fast-moving subjects.

Tim’s Quick Answer: While my previous answer related to a “fast lens” or “fast glass” emphasized autofocus performance, a lens with a larger maximum aperture size would indeed enable faster shutter speeds, all other things being equal.

More Detail: Every now and then an installment of my Ask Tim Grey eNewsletter leads to a surprising number of responses from photographers, and the subject of “fast lenses” led to an especially large number of replies. It is certainly fair that a lens with a larger maximum aperture size would enable a faster shutter speed, but I would consider that a secondary factor in the context of today’s technology.

As many photographers reminded me, the term “fast glass” for lenses predates autofocus. I suppose that wasn’t as strong in my perspective because while I started out using only manual focus lenses, for most of my time as a photographer I’ve had the luxury of autofocus.

In addition, with the common availability of lens stabilization technology in lenses and camera bodies, it has become less important to choose a fast lens for purposes of achieving a faster shutter speed. For example, when a lens is available in models that feature a maximum aperture size of f/2.8 versus f/4, having image stabilization technology will provide a greater advantage than the additional stop of light via the aperture.

So, while I agree that the term “fast lens” or “fast glass” was in use before autofocus was available, I do think that autofocus performance is a more important reason to consider opting for a lens that has a larger maximum aperture size compared to the ability to achieve faster shutter speeds.

And, of course, as a photographer who tends to favor capturing photos with narrow depth of field, a wider aperture can enable you to create images with less of the scene in focus as well.

I very much appreciate the photographers who replied to my original email on the subject of fast lenses. One of the things I have always enjoyed about publishing the Ask Tim Grey eNewsletter is that readers are quick to respond if they find something I’ve left out, that I’ve stated incorrectly, or that they simply disagree with me about. The feedback is appreciated.

Today’s Question: For composite imaging in Photoshop, what’s the best way to select two images from two different folders in Lightroom Classic?

Tim’s Quick Answer: You can browse the photos from two or more folders at the same time, and then use filters to narrow down the list so you can more easily find the two photos you want to use. Alternatively, I would recommend using the Quick Collection to temporarily group the images together.

More Detail: You can browse the photos from more than one folder in Lightroom Classic by simply selecting multiple folders. This can be done in the same way you would select multiple files or folders in the operating system. You can click on the first folder and then hold the Shift key while clicking the last folder to select the full range of folders in between. You can also toggle the selection of folders on or off by holding the Ctrl key on Windows or the Command key on Macintosh while clicking on a folder.

Once you’ve selected multiple folders you can use the filter settings on the Library Filter bar to narrow the photos down, such as by star rating or other metadata values.

Another great option is to use the Quick Collection in the Catalog section of the left panel in the Library module to group the photos together temporarily. In general, I recommend that you first make sure the Quick Collection is empty. If you need to preserve the group of images currently in the Quick Collection you can save them to a normal collection by right-clicking on the Quick Collection and choosing “Save Quick Collection” from the popup menu.

You can clear the current images from the Quick Collection by right-clicking on it and choosing “Clear Quick Collection” from the popup menu. I then recommend making sure the Quick Collection is the current target collection, which you can do by once again right-clicking and choosing “Set as Target Collection”.

With the Quick Collection set as the target collection you can add images to the Quick Collection by pressing the letter “B” on the keyboard. You could then navigate among the various folders that contain images you want to work with, select a photo, and press “B” on the keyboard to add the selected image to the Quick Collection. You can then go to the Quick Collection to browse the photos you’ve grouped there, select the photos you want to work, and then send them to Photoshop to create a composite.

Today’s Question: In response to your answer about adding GPS metadata by dragging photos to the map [in Lightroom Classic], isn’t it also possible to use a smartphone to record GPS data and add it to photos?

Tim’s Quick Answer: Yes, you can use a smartphone app to record a track log during a photography outing, and then synchronize that track log with the photos in Lightroom Classic to add location metadata to the images.

More Detail: The easiest way to add GPS metadata to your photos is to capture those photos with a camera that has a GPS receiver. With this approach your photos will have GPS information added to metadata automatically, so the photos will simply appear on the map in Lightroom Classic with no additional effort.

As noted in a previous answer, it is also possible to drag photos to the map in order to add location information to metadata. However, recording a track log makes that task even easier when you’re using a camera that doesn’t have a built-in GPS receiver or an attached accessory device.

Some GPS navigators and similar devices have the ability to record a track log. You can also use a smartphone app for this purpose. For the iPhone I use an app called GPS Tracks (https://timgrey.me/gpstracks). For Android users I’ve tested an app called A-GPS Tracker (https://timgrey.me/gpstracker) and found it to work well.

The process of using a track log to add GPS coordinates to the metadata for photos is relatively straightforward. You record the track log in the GPX format (not the KML format) and then I recommend saving that track log in the same folder with the photos it corresponds to.

In the Map module in Lightroom Classic you then select the photos on the filmstrip that relate to the track log, click the track log button on the toolbar below the map, and choose “Load Tracklog” from the popup menu. With the track log loaded and the photos selected, click the track log button again and choose “Auto-Tag Selected Photos”.

The capture time for the photos will be synchronized with the time from the track log, so that GPS coordinates can be determined and added to the metadata for each photo.

Today’s Question: What does it mean for a lens to be “fast”? I see references to “fast glass”, but I don’t understand what this means or how it would benefit me.

Tim’s Quick Answer: A fast lens is one that will achieve autofocus faster based on a relatively large lens aperture (small f-number).

More Detail: When a lens features a lens aperture that can open to a larger size (smaller f-number) it allows more light to reach the image sensor. That, in turn, means that the lens will generally be able to achieve autofocus more quickly, thanks to the additional light. This also means the lens is capable of providing narrower depth of field since the lens aperture can be opened to a larger diameter.

Strictly from the standpoint of autofocus, this means that you’ll get better performance with a lens that features a larger maximum aperture size. For example, an f/2.8 lens is capable of faster autofocus than an f/4 lens, all other things being equal. This is one of the reasons, for example, that some lenses are available in two different models with different maximum aperture sizes, with otherwise identical specifications.

A lens with a larger maximum aperture size will generally be more expensive than a lens that doesn’t have as large a maximum aperture size. It is therefore worthwhile to consider whether you actually need the faster autofocus performance.

For some types of photography, such as birds in flight and sports, faster autofocus performance can be very important. For other types of photography, such as landscape photography, the autofocus performance generally won’t be as important. Therefore, the maximum lens aperture size is only one factor to consider, taking into account how important faster autofocus is to you, along with the potential for narrower depth of field afforded by a lens with a larger maximum aperture size.

Today’s Question: I don’t have a GPS receiver on my camera, though of course my iPhone records where I am if I import iPhone images into Lightroom Classic. Is it possible when importing images to say that, for example, a batch are from Rome, another batch from Istanbul, so in the future I could go to the map, point to a place, and see all the images ever taken there?

Tim’s Quick Answer: There’s not a particularly efficient way of adding GPS metadata to images during import in Lightroom Classic. However, you could apply location-based keywords during import, or you can add GPS metadata to the photos quite easily after import.

More Detail: It would technically be feasible to assign GPS metadata to images upon import into Lightroom Classic by creating a metadata preset that contains GPS coordinates and applying that preset during import. However, this would require the extra effort of creating a metadata preset prior to import, and would not provide the flexibility of using multiple locations for a single batch of photos being imported.

As a very basic workaround you could assign location-based keywords during import, such as adding the name of the city and country where the photographs were captured. This would enable you to locate the applicable photos such as by using the filter option for keywords on the Keyword List in the Library module, but it would not enable you to locate photos based on the map.

However, you can very easily add location information to photos using the Map module. Simply select a group of photos on the filmstrip and drag-and-drop them onto the map in the applicable location. This will add pins on the map representing the photos that were added to the map, and also add GPS coordinates to metadata representing the position on the map the photos were dragged to.

You could certainly drag photos to the specific location on the map where they were captured, provided you could recall those details for all (or some) of the photos. However, you can also use a somewhat generic location on the map for a group of photos.

For example, you could select all photos captured in Rome, Italy, and drag them onto the map at Piazza Navona in the heart of Rome. This would obviously mean that for many of the photos the exact GPS coordinates added to metadata weren’t accurate, but as long as you took that into account when browsing the map or the GPS metadata that wouldn’t be a significant problem.

Today’s Question: Can keep my photos and my Lightroom catalogs synchronized on two computers, so that they are identical? I use a desktop iMac for my photography management and serious editing. Sometimes I take trips, though, and when I take photos on those trips, I like to see the photos and edit them on my MacBook Pro laptop. I know a simple solution is to keep the photos and catalogs on an external hard drive, but since my data storage is all on a RAID array, that isn’t feasible.

Tim’s Quick Answer: The only dependable way I would recommend having a full Lightroom Classic catalog and the related photos on two computers is to store the catalog and photos on an external hard drive that can be moved between computers. Since that isn’t feasible, I suggest using a traveling catalog for photos captured during a trip, and synchronization to the Creative Cloud for photos you want to have available for sharing during the trip.

More Detail: Because of the way Lightroom Classic is designed, it isn’t straightforward to make a catalog available on two computers at the same time. The catalog, for example, cannot be stored on a network storage location. I also strongly recommend against storing the catalog with a cloud-based storage service.

If it isn’t feasible to have the Lightroom Classic catalog (and possibly photos) stored on an external drive, then I recommend using a combination of a traveling catalog and cloud-based synchronization to provide similar functionality.

For photos captured during the trip, you can use a dedicated catalog for that trip. You can work in Lightroom Classic in the normal way making use of any features you’d like during the trip, and when you get home you can merge that traveling catalog with your master catalog and then all the work you did in the traveling catalog will be reflected in the master catalog.

To enable sharing photos from your master catalog during a trip I recommend making collections for the photos you want to share, and then enable synchronization for those collections. You can then use the Lightroom app on a mobile device, or Lightroom in a web browser (https://lightroom.adobe.com) on your laptop, to share photos with others via those synchronized collections.

Today’s Question: I know it is possible to automatically synchronize adjustments in Lightroom Classic so I can apply the same adjustments to multiple photos at a time. But can I copy only the image cleanup work from one photo to another? I spent considerable time cleaning up dust spots in one image, only to then realize the same cleanup was needed for a series of other images. Can I duplicate that work easily?

Tim’s Quick Answer: Yes, you can synchronize only the image cleanup work from one image to others in Lightroom Classic using the Synchronize Settings command and enabling only the Healing adjustments for synchronization.

More Detail: There are several ways you can synchronize adjustments in Lightroom Classic, including the Auto Sync option for synchronizing adjustments across multiple images in real time. However, that doesn’t help when you realize you need to duplicate previous adjustments to other images.

Image cleanup is a great example of this type of situation, because if you have dust spots on the image sensor those spots will appear in exactly the same position for all photos captured with the same dust on the sensor. In this type of situation you can use the Synchronize Settings command to synchronize selected adjustments from one image to a group of others.

Since the adjustments—in this case image cleanup work—had already been applied, you have a reference image that represents the source of the adjustments you want to synchronize to other images. Therefore, the first step is to select the images you want to synchronize the adjusts to, along with the image you’ve already adjusted.

With that range of images selected, click on the thumbnail—note the frame around the thumbnail—for the image you’ve already applied the adjustments to. That will make the image you clicked on the active image, while still keeping the other image selected.

On the right panel in the Develop module you can now click the Sync button. If the button says “Auto Sync” instead, click the toggle switch on the left side of the button to disable automatic synchronization, and then click the Sync button.

In the Synchronize Settings dialog that appears you can click the “Check None” button at the bottom-left of the dialog to turn off the checkboxes for all adjustments. Then, in this example, turn on the “Healing” checkbox, so that you’ll be synchronizing the image cleanup work. You can also turn on any checkboxes for other adjustments you’d like to synchronize from the active image to the other selected images.

Click the Synchronize button at the bottom-right corner of the Synchronize Settings dialog, and the adjustments for which you turned on the checkbox will be synchronized from the active image to the other selected images. In this case that means the image cleanup work done for the first image will be applied to the other selected images.

Today’s Question: Is there a way to see the only the original images that were imported into Lightroom Classic, rather than the many copies that might coexist side by side?

Tim’s Quick Answer: You can set a filter for “Original Photos” to exclude virtual copies from the current view. You can also filter based on file type, such as to only display raw captures.

More Detail: In Lightroom Classic you can create additional copies of an original photo in two ways. You can create a virtual copy, which represents an additional set of metadata (such as adjustments) for the same source image. You can also create an entirely new file, such as a TIFF image that might be created when you send a photo to Photoshop or another external editor or plugin.

To exclude virtual copies, you can select the “Original Photos” option associated with the Kind setting on the Attribute tab of the Library Filter bar. If the Library Filter bar isn’t displayed, you can choose View > Show Filter Bar from the menu. Then go to the Attribute tab and click the first button to the right of the Kind label, which is the “Original Photos” option. The second button is for virtual copies and the third is for videos, so you can toggle each of those buttons on or off based on the filter you want to apply.

To exclude derivative copies of the source image that were saved in a file format such as TIFF, PSD, or JPEG, you can set a filter for the file type. On the Metadata tab of the Library Filter bar click one of the column headings representing the metadata fields for filtering and choose “File Type” from the popup. Within the File Type column choose “Raw” to filter based on raw captures, so that other file types will not be displayed.

Note that if you have a mix of virtual copies as well as derivative image types you can enable both filter settings outlined above to exclude everything except original raw captures.