Category: Ask Tim Grey

Today’s Question: How does one know how many aperture blades a lens has?

Tim’s Quick Answer: While it can sometimes be a little challenging to find this specification, I’ve found that in general the B&H Photo website is a reliable source for this information. The number of blades is listed on the Specs tab for the product page for lenses, listed as “Diaphragm Blades”. You can see an example by scrolling down and selecting the Specs tab on this page:

https://bhpho.to/2KKZebt

More Detail: Today’s question was a follow-up to information I shared about creating a starburst effect with the sun or other non-diffused light source. As many photographers are aware, you can achieve a starburst effect by stopping the lens down to a relatively small aperture size, such as f/16 or f/22.

What I find many photographers are not aware of, however, is how the number of lens aperture blades affects the starburst effect. If there are an even number of lens aperture blades, the starburst effect will have the same number of light rays as there are lens apertures.

If the lens aperture has an odd number of blades, the starburst effect will have twice the number of light rays as there are aperture blades. I’ve cited one example of a photo I captured at sunrise, specifically choosing to use the Tamron 15-30mm lens because it has nine aperture blades, and therefore would provide a starburst effect with eighteen light rays emanating from the light source (in this case the sun).

You can see the photo in question, showing 18 light rays around the sun, on my Instagram feed here:

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

Another reason to consider the number of blades (and shape) of the lens aperture is the shape of bokeh effects and lens flare. Many photographers prefer a very smooth, rounded bokeh effect for example, which calls for rounded rather than straight lens aperture blade edges. More aperture blades can also result in a smoother lens aperture curvature shape, resulting in smoother bokeh.

So, while the number of blades that makes up the lens aperture in a given lens may seem like a rather esoteric specification, there are certainly scenarios in photography where you may want to consider the details of the aperture configuration for a lens.

Today’s Question: Is Lightroom no longer available as a local (desktop) based application, or is it only a cloud only based application?

Tim’s Quick Answer: Lightroom Classic is indeed still available as a desktop-based application that does not require cloud-based storage. That is in addition to the cloud-based version of Lightroom that runs on the desktop but revolves around cloud-based storage. As with most Adobe applications, both of these versions of Lightroom require a Creative Cloud subscription.

More Detail: Both Lightroom Classic and Lightroom are desktop applications that run on your computer. There are also mobile and web browser-based versions of Lightroom.

The two desktop applications both require a Creative Cloud subscription, such as the Creative Cloud Photography Plan (https://timgrey.me/ccplans). Both of these applications are able to store photos in the cloud, meaning on servers via an internet connection. The key difference is the way overall storage of your photos is managed.

With Lightroom Classic, you manager your photo storage yourself locally. That would typically mean storing your photos on one or more hard drives, for example. Photos are only synchronized to the Adobe Creative Cloud servers if you add photos to a collection with synchronization enabled.

With the cloud-based version of Lightroom, the cloud-based storage is your primary storage. Provided there is enough storage space on your computer, all of your photos can also be synchronized to the computer. But if there is not enough storage space, all of your photos will be on the Creative Cloud servers, but won’t necessarily be synchronized to your computer. In addition, you don’t have direct control over the folder structure for your photos with the cloud-based version of Lightroom, so you would need to use albums, keywords, and other features in place of a folder structure for organizing photos.

My personal preference is to use Lightroom Classic to manage my workflow, in large part because I prefer to manage my storage locally, and don’t want or need to have every single photo synchronized via the internet. However, each photographer should consider their own priorities when choosing between Lightroom Classic and Lightroom, or different software altogether.

Today’s Question: In semi-automatic modes like shutter priority and aperture priority, we set two of the three important settings for exposure: ISO and either shutter speed or lens aperture. The camera picks the third and has control of the overall exposure. If we use manual exposure but with auto-ISO, doesn’t this become a third semi-automatic mode with the camera having control of one of the three settings? Then it really isn’t manual at all? Is exposure compensation then an important and effective setting just like in the other semi-automatic modes?

Tim’s Quick Answer: Yes, if you enable auto ISO when using the manual exposure mode, the camera is then operating in a semi-automatic rather than fully manual exposure mode.

More Detail: A proper exposure involves the use of a given lens aperture, shutter speed, and ISO setting. There are a variety of ways you can achieve specific settings, including fully automatic, semi-automatic, and manual modes.

In a fully automatic mode, the camera typically chooses all three exposure settings for you. In a true manual exposure mode, you need to adjust all three settings yourself. And in semi-automatic modes you are typically able to select one or two of the exposure settings, with the camera selecting the other setting for you.

So, if you enable auto ISO when using manual exposure mode, the exposure control is no longer fully manual. As you adjust the lens aperture or shutter speed, the ISO will adjust as well to maintain the metered exposure. That also means that exposure compensation become important when using manual mode in conjunction with auto ISO, just as exposure compensation is important with other semi-automatic exposure modes.

Exposure compensation enables you to shift the exposure brighter or darker relative to the exposure calculated by the camera based on the meter reading. Normally when using manual exposure mode, the exposure compensation setting for the camera wouldn’t apply, as you would simply adjust the exposure settings to the desired meter reading. However, with auto ISO you can apply exposure compensation with manual exposure. This would alter the selection of the ISO setting to achieve the target exposure based on compensation, and in conjunction with the lens aperture and shutter speed settings you have selected.

Today’s Question: I shot a wedding with a second shooter and she forgot to sync her time with my camera’s. The capture time in all her photos is 2 hours and 45 minutes earlier than mine. I tried to fix this in Lightroom Classic. For what I understand the “change capture time” options are either to put in the correct time individually for each photo or add or subtract the number of hours of your choice, but I don’t have an even number for the correction. Do you have any suggestions for doing this an easier way?

Tim’s Quick Answer: You can synchronize the capture times for all photos captured by the second camera in this case by using the option to adjust to a specific date and time, which actually makes it possible to adjust by a specific amount of time not just set the capture time for all photos to the same time.

More Detail: I imagine the most common correction for capture time is a time zone correction, as I have most certainly neglected to update the time on my camera on more than one occasion when crossing time zones. However, it is also possible to correct capture times by a “random” number of hours and minutes in Lightroom Classic.

The key is to first determine what the actual correct capture time would be for one of the photos, so you can determine the offset to use for the capture time correction. For example, with two photographers you may be able to find a photo captured at about the same moment and use the capture times for those two photos as a reference. So here, for example, the photographer has determined that the correction is 2 hours and 45 minutes.

You can then filter the images captured with the camera requiring correction, sort by capture time, and then take a look at the very first photo from that camera. Using the example from today’s question of 2 hours and 45 minutes difference, let’s assume that the capture time for the first photo was precisely 12:00pm (because that makes the math here a little easier for me).

Based on this, you would know that the correct capture time for that first photo would actually be 2:45pm. Let’s further assume that the second photo was captured at 12:05pm, and all the remaining photos were of course captured at later times.

Select all of the photos that need to be corrected, with the first photo in the sequence being the active photo (the photo you see in the loupe view display for example). Then choose Metadata > Edit Capture Time from the menu.

In the dialog that appears, first choose the “Adjust to a specified date and time” option under the Type of Adjustment heading. Then set the Corrected Time to the correct value. In this example the Original Time will show the date and 12:00:00pm, so I would set the Corrected Time to 2:45:00pm.

When you click the Change button to update the capture time, you won’t actually be changing every selected photo to be set to a 2:45pm capture time, even though the wording in the dialog makes it sound that way. Rather, you’ll be updating the capture time to the value you enter for Corrected Time for the active photo, and all other photos will be corrected based on their relative capture time.

So here, for example, the first photo will of course be corrected to a capture time of 2:45pm, and the second photo will be updated to 2:50pm, and all other photos will be updated with the same time shift, which in this case was 2 hours and 45 minutes.

Today’s Question: Why am I not able to ever select “Depth” from the Range Mask popup for targeted adjustments in Lightroom Classic? For every image I can only choose “Color” or “Luminance”, even though I can see that Depth is also on the popup but disabled.

Tim’s Quick Answer: The Depth option for the Range Mask control is only available for images with an embedded depth map, such as photos captured in Portrait mode with an iPhone.

More Detail: The Range Mask controls enable you to refine a targeted adjustment in Lightroom Classic based on luminance values, color values, or distance from the camera. The Depth option on the Range Mask popup relates to distance from the camera and requires that the image has an embedded depth map that defines the distances within the scene.

When you capture a photo in Portrait mode using an iPhone, for example, the camera determines the distance from the camera for the various elements in the scene. A depth map is created, which uses shades of gray to map out the distances throughout the scene. That depth map is embedded in the photo.

The iPhone uses the depth map to determine which portion of the image should be sharp versus blurred to create a narrow depth of field effect. However, other software can also make use of that embedded depth map, such as to apply targeted adjustments.

Lightroom Classic is able to employ the depth map to refine a targeted adjustment, with the Graduated Filter, Radial Filter, and Adjustment Brush. For example, let’s assume you have applied a targeted adjustment that darkens the image in a gradient from top to bottom. That adjustment would of course affect the entire image in a gradient fashion.

With the Depth option for the Range Mask feature, you can limit that graduated adjustment, so it only affects areas of the image that represent a particular range of distances from the camera. So, for example, you can have the graduated adjustment only affect the background of the image, without affecting a foreground subject.

While this ability to refine a targeted adjustment is impressive, it is important to note that the accuracy of the range mask is somewhat limited. I often see artifacts in the depth map that cause targeted adjustments to not be precisely applied to the intended areas of the photo.

Today’s Question: [In Lightroom Classic] Assuming you have the “save changes to xmp” option turned on, when you create a virtual copy does it save the info from both the virtual and original to the xmp file? Or create a separate xmp? Or keep the data for the virtual copy only within the catalog?

Tim’s Quick Answer: The metadata related to virtual copies in Lightroom Classic is only saved in the catalog, not in an XMP sidecar file as would be the case for the metadata related to the master image.

More Detail: I recommend turning on the “Automatically write changes into XMP” checkbox on the metadata tab of the Catalog Settings dialog in Lightroom Classic. This will cause updates to standard metadata fields (but not Lightroom-specific metadata) to be written to the source image file on your hard drive, which in the case of a raw capture means that the information will be written to an XMP “sidecar” file.

However, for virtual copies, the metadata updates are only saved in the Lightroom Classic catalog. The XMP sidecar file for the original raw capture will not contain the information for the virtual copy.

If you export the virtual copy, the information from the virtual copy will be included in the metadata for that image, assuming you include metadata as part of the export. For example, if you export a virtual copy of a raw capture with the “Original” option selected for the Image Format setting, an XMP sidecar file will be created with the metadata from the virtual copy.

So, in general virtual copies should be thought of as a Lightroom-specific feature, meaning standard metadata that might otherwise be written to original image files (or XMP sidecar files in the case of raw captures) will not be written to a file for virtual copies. It is also worth noting that other Lightroom-specific features are not reflected in metadata, even when you have the option to write metadata to XMP enabled.

For example, pick and reject flags, inclusion in collections, virtual copies, and history are not written to metadata for images. Rather, these Lightroom-specific features are only saved within the Lightroom Classic catalog, which is one of the reasons it is still important to back up your catalog, even if you have the option enabled to automatically write metadata updates to the source image files.

Today’s Question: I have routinely edited or processed my original raw images in Lightroom Classic. Now I have a reason to go back to the original raw image, but I am not sure how. Maybe I should have created a “Virtual Copy” and performed all my processing on that version? Can I get back to the original now?

Tim’s Quick Answer: You can indeed reset to the original version of a raw capture in Lightroom Classic by clicking the Reset button at the bottom of the right panel in the Develop module. If you want to preserve the edited version of the image you can create a virtual copy before using the reset option.

More Detail: All of the adjustments you apply in the Develop module in Lightroom Classic are non-destructive, meaning they don’t actually alter the original image file on your hard drive. That means you can modify or reset any (or all) of the adjustments you’ve applied.

If you want to keep both the edited version and the original version of the photo, you can create a virtual copy first. Simply right-click on the photo in question and choose “Create Virtual Copy” from the popup menu that appears. This virtual copy will have the exact same adjustment settings as the original photo.

You can then select either the original photo or the virtual copy and click the Reset button at the bottom of the right panel in the Develop module to reset all adjustments to their defaults. You could then apply new adjustments to that image after resetting it, or simply retain the original version for reference.

Note, by the way, that creating a virtual copy does not create a copy of the original image file, so it does not consume any real hard drive space. It is simply another set of metadata for the same source image. So the original image will have one set of adjustments in the Develop module, and the virtual copy can have a different set of adjustments.

Today’s Question: I have Lightroom Classic on a desktop and also on a laptop. I have my image files on an external hard drive on the desktop. If I disconnect the external hard drive from my desktop and connect it to the laptop, make changes to the image files then disconnect from the laptop and connect again to the desktop, will Lightroom Classic on the desktop recognize the changes that I made on the laptop?

Tim’s Quick Answer: If the Lightroom Classic catalog is on the external hard drive then you can switch among computers and preserve all updates regardless of which computer you’re working on. If you have a separate catalog on two computers, this workflow will absolutely not work and will likely lead to a significant mess in Lightroom Classic.

More Detail: Lightroom Classic keeps track of the information about your photos through the use of a catalog, which is a database at the core of your Lightroom Classic workflow. I highly recommend using a single catalog to manage all of your photos, rather than multiple catalogs. And when it comes to working on two different computers, it is even more important that you’re using a single catalog whenever you’re using Lightroom Classic.

Normally I recommend having your catalog files on your computer’s internal hard drive in order to maximize performance. However, if you want to be able to work across two computers with the same catalog, I recommend storing the catalog on an external hard drive.

With your Lightroom Classic catalog and all of your photos on an external hard drive, you can move that hard drive between computers. Since you’ll be using the same catalog file with Lightroom Classic on two different computers (but only one computer at a time) all updates you make will be reflected on both computers.

If, on the other hand, you were to maintain individual catalogs on two computers, moving the photos between the two computers, your updates would not be synchronized across the two computers. Both catalogs would remain independent, and you would therefore end up with a significant mess relatively quickly, where different updates have been applied in different catalogs.

It is worth noting, by the way, that this sort of issue is not a factor with the cloud-based version of Lightroom. You can have this version of Lightroom on two computers, and updates from one computer will be reflected on the other, as well as on mobile devices with the Lightroom app installed. That said, I still prefer Lightroom Classic over the cloud-based version of Lightroom for a variety of reasons, including preferring to manage my folder structure locally.

Today’s Question: How can words with special alphabet characters (such as Dragør, smörgåsbord, Värmland, Nærøy Fjords) be included in keywords for Lightroom Classic?

Tim’s Quick Answer: Yes, you can most certainly use special characters in keywords in Lightroom Classic. These include both symbols and characters from foreign languages.

More Detail: It is important to have something of a strategy when it comes to keywording your photos, and that includes thinking about spelling. For example, will you use the local language for the names of places (such as Firenze, Italia) or the name used in your own language (such as Florence, Italy)?

Taken a step further, you can decide if you will use special characters such as those from other languages, or a variation based on your own language. For example, will you include an “O” with the umlaut to add “Österreich” as a keyword, or will you leave the umlaut off and use “Osterreich”, or will you use the English version of “Austria”?

For some special characters you can use keyboard shortcuts. In other cases, you may need to use an international keyboard setting for the operating system. In addition, software such as a word processor application can be used to type words with special characters, which you can then copy-and-paste into the Keywords in Lightroom Classic.

Today’s Question: I’ve seen you reference Camera Raw in addition to Lightroom Classic for assembling an HDR [high dynamic range] image from bracketed raw exposures. But how do you actually assemble an HDR image using Camera Raw?

Tim’s Quick Answer: You can assemble an HDR image (or a panorama or even an HDR panorama) in Adobe Camera Raw by opening all of the images in Camera Raw, selecting all of those photos on the filmstrip, and then right-clicking and choosing the applicable “Merge to” option from the popup menu.

More Detail: I recommend starting in Adobe Bridge when you want to open multiple photos in Photoshop. After selecting the raw captures that you want to assemble into an HDR image (or into a panorama or HDR panorama) double-click on the thumbnail of one of the selected photos. This will open the raw captures in Adobe Camera Raw.

With the images open in Camera Raw, you should see a filmstrip with the thumbnails for all of the raw captures you opened. If not, you can click the filmstrip button toward the bottom-left of the Camera Raw interface. That button has one large rectangle and four small rectangles, representing the filmstrip display.

On the filmstrip you can then select all of the raw captures. You can hold the Ctrl/Command key while pressing the letter “A” on the keyboard, or click the first image and hold the Shift key while clicking the last image.

With all of the raw captures selected you can then right-click on the thumbnail for any of the images, and then choose “Merge to HDR” (or the options for a panorama or HDR panorama as applicable), which will bring up the dialog with the settings for merging the images together. Note, by the way, that when you hover your mouse over one of the thumbnails in Camera Raw, there is also an ellipsis button (three circles) that appears, and you can click on the ellipsis to bring up the menu where you can select the “Merge to” command.