Ask Tim Grey

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.

Today’s Question: A question [in Friday’s Ask Tim Grey eNewsletter] suggested photos would have very little noise if captured at the camera’s lowest ISO setting. But aren’t there other factors that cause noise in photos besides the ISO setting?

Tim’s Quick Answer: While a high ISO setting can significantly contribute to noise in a digital photo, there are indeed other factors such as the exposure time, the brightness of the exposure, and heat buildup in the camera.

More Detail: For most digital cameras a relatively low ISO setting will help minimize the level of noise in photos. However, there are other factors that can contribute to noise as well.

Long exposures will exhibit more noise that short exposures, all other factors being equal. If you photograph the exact same scene with the exact same overall exposure, but with different shutter speeds, the image with a longer exposure time will have more noise. This is especially true for particularly long exposures, which is why many cameras include a long exposure noise reduction feature that reduces noise for exposures of around one second or longer.

An under-exposed image will also exhibit more noise than a properly exposed photo. This is why the concept of “expose to the right” is helpful. By capturing an image that is as bright as possible without clipping the highlight detail, you are capturing maximum information (light) and therefore minimizing noise all other things being equal.

Heat buildup in the camera can also contribute significantly to noise in photos. This isn’t generally a problem under typical photographic conditions. However, if you capture a relatively large number of long exposures in a short period of time, heat buildup can be a factor, contributing to more noise in your photos.

Today’s Question: I almost always shoot at ISO 100. Consequently, there is very little noise present most of the time. I’m never quite sure whether to reduce the barely noticeable noise or if I should just leave well enough alone. What do you do in such a situation? I have never really read or heard anyone address this problem about when or when not to reduce noise shot at lower ISO settings.

Tim’s Quick Answer: Even when noise is minimal in an image, I recommend at least applying color noise reduction. I would only apply luminance noise reduction if the noise was significant enough to detract from the overall quality of the image.

More Detail: Noise is unavoidable in digital photos, so the real question is how much noise is present. Even under optimal conditions, however, if you can see color noise when you zoom in to a 100% zoom setting for the image, I feel you should apply color noise reduction.

When applying color noise reduction, it is important not to be too aggressive. In some cases, you may be able to remove all visible color noise. However, if you apply settings that are too strong you may cause color artifacts due to the averaging and blending of color values caused by color noise reduction.

With luminance noise reduction the risk of causing problems in the photo are more significant. Strong luminance noise reduction will have the effect of blurring the photo, reducing the amount of texture and detail that is apparent in the image.

Therefore, when applying luminance noise reduction, it is especially important to carefully evaluate the settings, striking a balance between reducing the perceived noise and retaining texture and detail in the photo.

Based on all of this, I would generally apply color noise reduction for any image where you can see color noise. I would only apply luminance noise reduction if there is a fair amount of luminance noise, to the point that the noise is clearly contributing to the appearance of reduced image quality. If luminance noise is minimal or barely noticeable, I would tend not to apply luminance noise reduction.

Today’s Question: If you rename photos upon import into Lightroom Classic, and later delete some of those photos, you’ll have gaps in the numbering for the images. Is that not a concern, or would it be better to rename later in your workflow?

Tim’s Quick Answer: I don’t consider it a significant issue to have gaps in the sequence numbers for filenames, but I certainly understand the desire to avoid those gaps. If you do prefer to rename photos after you have deleted outtakes, I do recommend being sure that the original filenames aren’t being referenced by others (such as clients) before you rename the photos.

More Detail: The primary reason I prefer to rename photos during import is to make sure that any reference to the filename will be a reference to the new filename. For example, if you had sent copies of photos to a client for review before renaming photos, they would be seeing the “old” filenames and you would be working with the “new” filenames.

Of course, if you later delete outtakes, you’ll have gaps in the sequence numbers for your filenames. So, if you want to avoid those gaps in sequence numbers, you can wait until you’re finished reviewing photos and deleting any outtakes.

Keep in mind, by the way, that if you do rename photos in Lightroom Classic either during import or later in your workflow, the original filename will be retained in metadata. For photos that have been renamed by Lightroom Classic, you’ll find the original filename in the Preserved File Name field in the Metadata section of the right panel in the Library module, after selecting the “Default” option from the popup to the left of the Metadata heading.

However, this “Preserved File Name” metadata field is not searchable natively in Lightroom Classic, so actually locating a photo based on the original filename can be a bit tricky. You would need to use a filter plug-in such as Any Filter by John R. Ellis:

https://johnrellis.com/lightroom/anyfilter.htm

Today’s Question: On your trip around the world with one lens what does a histogram of focal length usage look like?

Tim’s Quick Answer: During my extended trip in 2019 that too me around the world, I used only a Tamron 18-400mm lens (https://bhpho.to/2DPkI3C). Looking at the data, I see that about 25% of the total number of photos were captured either at the maximum focal length (17% of the photos) or at the minimum focal length (about 8% of the photos).

More Detail: In early 2019 I had the opportunity to take an extended trip while teaching onboard a cruise ship. Between flights and travel on the ship, I ended up traveling all the way around the planet. For fun, I decided to only bring a single lens with me. For maximum flexibility though, I opted for the Tamron 18-400mm lens.

I created a histogram chart of the distribution of focal lengths used during the trip. But as noted above, a significant percentage of the images were captured at either the maximum or minimum focal length I had available.

You can read a bit more, and see a chart of the focal length distribution, on the GreyLearning blog here:

https://greylearningblog.com/focal-length-distribution-around-the-world/

In addition, you can view a recording of the presentation I gave as part of the GreyLearning Webinar Series titled “Lessons Learned Around the World with One Lens” on my Tim Grey TV channel on YouTube here:

https://youtu.be/dOHcN1fzvw4

Today’s Question: Is there a compelling reason to save the source images after they have been merged to make an HDR [high dynamic range] image in Lightroom Classic? My main reason for asking is that I use the Nikon D850 which creates large files and, while I understand storage is cheap, I just don’t see a reason to keep the source files since I can make further post processing changes to the HDR image.

Tim’s Quick Answer: Once you have created an HDR image based on bracketed exposures and confirmed there are no issues with the resulting DNG file created by Lightroom Classic (or Adobe Camera Raw), I would say there is not a critical need to retain the original raw captures used to create the HDR image. That said, I do personally prefer to retain those original captures “just in case”.

More Detail: Deleting an original raw capture file is often compared to throwing away a slide or negative (for those of us who remember the days when photography was only film-based). However, in the context of assembling an HDR image or a composite panorama from a set of original captures, this analogy doesn’t quite hold true.

When you assemble an HDR image in Lightroom Classic based on a set of bracketed raw captures, the result is an Adobe DNG file. That means in some ways you’re creating a raw capture that is a blend of several other raw captures. You have the same overall flexibility for making adjustments to that DNG file as you would for the original raw captures.

Therefore, there isn’t a significant reason to retain the original raw captures after creating an HDR based on those captures. However, there are a couple of things you’ll want to consider.

First, you’ll want to carefully evaluate the HDR image to make sure there are no quality issues. For example, if there was movement within the frame there may be ghosting artifacts, where a moving subject appears ghosted within the image. It is also possible that there would be alignment issues between the individual captures. So, zoom in and evaluate the overall image to make sure there are no quality issues in the HDR result.

Second, keep in mind that while software for processing raw captures has gotten rather mature, there is still the potential that new software updates will provide an advantage in terms of going back and re-processing the original captures into a new HDR result. I don’t consider this a serious concern, but it is worth giving some thought to.

I still retain my original raw captures even after blending them into an HDR result, but that is in large part just a state of mind on my part. It has been a very, very long time since I’ve gone back to re-process the original raw captures to a new HDR image after having created an HDR image that I was initially happy with.

Today’s Question: I saw a photo of a full moon within an arch at Arches National Park in an article, and I wondered if it was a composite since the moon appeared so large within the arch. Many of the comments suggest it may be real. Do you think such a photo is indeed possible?

Tim’s Quick Answer: It is indeed possible to have the moon appear at the relative size shown in the photo in question, provided the photographer was positioned about a half mile from the arch. You can view the image referenced in today’s question in the article here:

https://petapixel.com/2020/11/30/full-moon-photo-looks-like-mysterious-giant-eye-through-rock-arch-in-utah/

More Detail: Photographers often refer to “lens compression” to describe a situation where a scene appears compressed, meaning that distant objects appear relatively large and therefore relatively close to a foreground object. This effect is actually achieved by the photographer positioning themselves further from the subject. A long lens is simply used to crop that scene to create the desired photograph.

To have a moon appear large relative to a foreground subject, you need to move away from that foreground subject. In the case of the moon photo that is the subject of today’s question, my calculations indicate that the photographer would need to be about half a mile away from the arch. The number I came up with was actually 2,361.7 feet, which I calculated using the PhotoPills app (https://timgrey.me/pills).

One way to describe the size of the moon in the context of a foreground subject is to define the size as though the moon were painted on that foreground subject. For example, if the width of the arch was twenty feet and the moon fills half the width of the arch, we could refer to the moon as being ten feet wide (even though the actual diameter of the moon is about 2,158.8 miles).

The information I was able to find about the size of the North Window at Arches National Park featured in the photo didn’t make it clear what the inner dimensions might be. So rather than using the arch as a measurement tool, I used one of the people in the photo to estimate the size of the moon. Operating on the assumption that the person I selected was about five feet tall, I calculated the size of the moon to be about twenty feet. I believe this would provide a conservative estimate of the size of the moon, since I suspect the person was more than five feet tall.

So, using the Planner pill in PhotoPills, I made use of the geodetics feature to determine where you would need to stand in order to achieve a relative moon size of twenty feet. With the black pin (for the subject) on the North Window on the map I then tested out various other positions for the red pin (for the photographer). I got an indication of twenty feet for the relative size of the moon when the photographer position was at 2,361.7 feet.

I also used PhotoPills to determine the path of the moon on the date the photographer indicated he captured the photo, and based on my estimates the moon would indeed have appeared behind the arch, so it is possible that the photographer was able to plan for just the right position to feature the moon within the North Window arch.

So again, I obviously can’t state for a fact that the image in question wasn’t a composite, but it was certainly possible to achieve the image with a single capture. But my aim here is not to try to prove that the photo was real, but rather to demonstrate that such a photo is possible, and that you can plan ahead to create such a photo using a tool such as PhotoPills. You can learn more about planning this type of photo using the PhotoPills app, with my comprehensive course that can be found here:

https://timgrey.me/pills

Today’s Question: During a recent presentation on Lightroom Classic you frequently deleted an effect after painting with the Adjustment Brush, but I don’t know how you did it. Can you tell me how you deleted it?

Tim’s Quick Answer: There are two options for deleting an effect with the Adjustment Brush in Lightroom Classic. First, you can delete an entire targeted adjustment area by selecting the applicable edit pin and pressing the Delete key on the keyboard. Second, you can erase part of a targeted adjustment by switching to the Erase brush for the Adjustment Brush and painting into the area where you don’t want the effect applied.

More Detail: The Adjustment Brush in the Develop module of Lightroom Classic enables you to paint adjustments into specific areas of a photo. You can adjust the settings for the brush, such as size and feathering, and then paint within the image to apply the adjustment effect you set with the various sliders and controls. After painting you can refine the adjustment settings, but also refine the area being affected.

If you decide you’re not happy with a targeted adjustment you’ve applied with the Adjustment Brush, you can delete the entire adjustment area. Start by clicking the edit pin (the gray circle icon) on the image, representing the area you no longer want to apply an adjustment to. Then, with the edit pin selected, you can press the Delete key on the keyboard to completely remove that specific targeted adjustment area.

If you simply need to remove certain areas of the image from the targeted adjustment so those portions of the image will no longer be affected by the adjustment, you can instead use the Erase brush for the Adjustment Brush.

When working with the Adjustment Brush tool, at the bottom of the set of controls for the Adjustment Brush on the right panel, you’ll find links for “A”, “B”, and “Erase”. The “A” and “B” options simply provide you with quick access to two different brush settings. For example, you might have a large feathered brush configured for the “A” brush, and a small minimally feathered configuration for the “B” brush. Painting with either the “A” or “B” brush will cause the current adjustment settings to be applied in any areas of the image where you paint.

If you switch to the Erase brush you can erase the adjustment from specific areas of the photo by painting in those areas. In other words, you’re able to add to the area that is being affected by a targeted adjustment by painting with the “A” or “B” brushes, and you can subtract from the area being affected by painting with the Erase brush.

Today’s Question: I have a folder in Lightroom Classic and I can see in the Library module. However, one of the folders under the main folder does not appear in the Library module. When I click the import button, I see the folder listed in both the from and to columns. Why does it not show up in my folder when I am just looking for it in the library?

Tim’s Quick Answer: In order to be able to browse folders (or photos within those folders) in Lightroom Classic, you need to import the applicable photos into your catalog. In this case, however, it would probably be easiest to use the Synchronize Folder command.

More Detail: In this particular example the photos from the parent folder had been imported, but the photos in the subfolder either weren’t imported in the first place or the photos (and folders) were removed from the catalog at some point.

You could certainly use the Import command to import the photos within the subfolder, being sure to use the “Add” option at the top-center of the Import dialog rather than the default of “Copy”. This “Add” option enables you to import photos while keeping them in their current location.

However, I think the Synchronize Folder command is more streamlined for this purpose. Start by right-clicking on the parent folder in question. From the popup menu that appears, choose the “Synchronize Folder” command. The dialog that appears will provide an indication of how many new photos have been found in the folder and subfolders within the folder.

Note that if there were any photos that currently have a “missing” status in the folders, there is an option to remove those photos. I recommend turning off the “Remove missing photos from catalog” checkbox, at least initially. Then track down those missing photos if possible and reconnect them.

But in this case the issue is photos that are not currently represented in the Lightroom Classic catalog. So, make sure the “Import new photos” checkbox is turned on, and click the Synchronize button to finalize the change. The subfolder in question will be added under the parent folder, and the photos in that subfolder will then appear in your Lightroom Classic catalog.

Today’s Question: [As a follow-up to yesterday’s question about filtering based on multiple keywords in Lightroom Classic], How about using Metadata -> Keyword in multiple columns from left to right to do a cascade filter of the words in common?

Tim’s Quick Answer: Yes, you could absolutely use cascading Keyword filter columns in the Metadata section of the Library Filter bar in Lightroom Classic in order to filter photos that include all (rather than some) keywords.

More Detail: In yesterday’s Ask Tim Grey eNewsletter I explained how you can use the Text section of the Library Filter bar in Lightroom Classic to search for photos containing specific keywords. More to the point, I covered how you can use the “Contains All” option for a keyword search, so that only photos containing all (not just some) of the keywords will be included in the search results.

In addition, as suggested in today’s question, you could use the Metadata section of the Library Filter bar. When you choose the Metadata tab on the Library Filter bar, the default columns are Date, Camera, Lens, and (Color) Label. You can, however, change these columns or even add more columns.

So, you could start with the left-most column, and click the heading so you can select “Keyword” from the popup. Select the first keyword you want to require for your search from the list, and then change the next column heading to “Keyword” as well. In this way you can gradually narrow the search results.

When you select a keyword in the first column, the second column set to “Keyword” will only show keywords that have been added to metadata for photos that also contain the keyword from the first column. You could continue using multiple columns as needed to narrow the search results to only those images containing all of the keywords you have selected from the columns.

One of the advantages of this approach is that you don’t have to type the keywords manually, so there’s no risk of typing the keyword wrong when searching. Of course, the potential drawback of this approach is that you may need to scroll quite a ways down the list of keywords for the first column in order to get to the keyword you want to filter by initially.