Category: Ask Tim Grey

Today’s Question: When light painting I consistently get a blue color to foliage (greens). I have used a couple of different LED flashlights with similar results. Sometimes I am able to improve, but not completely correct, the issue in post by adjusting white balance and hue using the local adjustment brush in Lightroom Classic. Is there a better light source I can use for painting or some other fix that I can try?

Tim’s Quick Answer: I would recommend either finding a flashlight that can provide a warmer (more yellow to orange) color, or to make use of a colored gel of your LED flashlight.

More Detail: Many LED lights have a relatively neutral to blue color cast, often ranging from about 5,000 Kelvin to around 6,500 Kelvin or so. This can introduce a challenging mixed lighting situation when used as an illumination source for photos, such as when using a flashlight as a supplemental light for a light painting effect.

In most cases you’ll find that a somewhat “warmer” light source that has a somewhat yellow to orange color cast will work best. Some LED lights provide a color temperature adjustment, so you can shift between a warmer (more yellow) or cooler (more blue) illumination. You can also find LED lights that emit light with a warmer color cast.

In general I would aim for a light with a color temperature of about 3,000 Kelvin. An incandescent light bulb typically has a color temperature of around 2,400 to 3,000 Kelvin, for example. On the Kelvin scale a higher value is a cooler color appearance, so you definitely want a light with a value below 5,000 Kelvin, and closer to 3,000 Kelvin would be preferred.

Keep in mind that you can also use gels, which are typically colored translucent sheets of acetate you can place in front of the light source to shift the color of the light. There are various options available, many of which are designed to be mounted in front of flash units or other lights. You can also get a simple colored gel sheet to fashion your own modifier for the light you’ll be using, such as the option shown here:

http://timgrey.me/warmgel

Today’s Question: Is there an easy way to apply the exact same crop to more than one image in Lightroom Classic?

Tim’s Quick Answer: There are several ways to apply the same crop to more than one image, including synchronizing adjustments, using a preset, or simply using the same aspect ratio when cropping each image.

More Detail: If you want to apply the exact same crop to several images, you can select all of those images and then turn on the Auto Sync feature by clicking the toggle switch on the left side of the Sync button at the bottom of the right panel in the Develop module. When you then apply a crop to the active image, the same crop will apply to all of the selected images.

If you’ve already cropped an image and want to apply that crop to other images, you can start by selecting the image you cropped in addition to the other images you want to apply the same crop to. After selecting all of the images, click on the thumbnail for the image you already cropped to make sure it is the active image. Then click the Sync button at the bottom of the right panel in the Develop module. In the Synchronize Settings dialog that appears, turn on the checkbox for Crop, as well as any other adjustments you want to synchronize across the selected images.

You could also use a preset for applying the same crop (or other adjustments) to various images. Start by applying the desired crop to one image, and then create a new preset using the plus button to the right of the Presets heading on the left panel in the Develop module, including the crop (and any other desired adjustments) in that preset. You can then apply the preset to other images to crop with the same settings.

If you don’t necessarily want the exact crop applied to all images, but rather just want to use the same aspect ratio for the crop, you can lock a specific aspect ratio for the crop. After choosing the Crop tool click the popup to the right of the Aspect label, and either choose an available aspect ratio or choose Enter Custom to enter your own aspect ratio. Use the same option for the Aspect popup with other images, and the aspect ratio will match for all of the images while the specific crop can still be unique.

Today’s Question: I have always used PSD files [Photoshop Document file format] based on your recommendation many years ago when I was first getting into Photoshop and Adobe Camera Raw. In a recent newsletter you said you now use TIFF primarily. Why?

Tim’s Quick Answer: I currently use TIFF files rather than PSD files because both support the same capabilities, and the TIFF files will be smaller in the context of a workflow that revolves around Lightroom Classic.

More Detail: I originally used PSD files for the master version of my images because in early versions of Photoshop the PSD file format supported layers and other features specific to Photoshop, while TIFF files did not. Therefore, PSD files were used for the layered master images, and TIFF files were used for flattened derivative images.

When Photoshop was updated to support layers for TIFF images, I continued to use the same approach of having PSD files be the layered version and TIFF files be the flattened version, mostly just out of habit.

However, with Lightroom Classic you are not able to import Photoshop PSD files unless the Maximize Compatibility option was enabled for the PSD file. The Maximize Compatibility setting causes what is effectively a flattened version of the image to be embedded within the file, causing an increase in file size equal to what a flattened copy of the image would be. For example, if the file contains no layers, the Maximize Compatibility feature would cause the file size to double.

TIFF images do not require a Maximize Compatibility feature to be supported by Lightroom Classic. Therefore, a TIFF file will always be smaller than an equivalent PSD file that is supported by Lightroom Classic.

Note that both PSD and TIFF formats are able to use compression to help reduce the file size. However, even with compression for the PSD file, the Maximize Compatibility feature more than makes up for the reduced file size, causing the file to be larger than an equivalent TIFF file.

Both TIFF and PSD files support saving the same features in Photoshop, so either will work perfectly well. But in the context of Lightroom Classic, the TIFF file will generally be significantly smaller, and therefore is my preferred file format between the two.

Today’s Question: In the context of fine resolution of details in a large print size, what is the difference between, say, a 26-megapixel APS-C sensor versus a 26-megapixel full-frame sensor? Will the full frame sensor be that much better to be worth the extra cost?

Tim’s Quick Answer: All other things being equal, including the number of megapixels for the sensors, the full-frame sensor will generally offer greater dynamic range and lower noise levels, which can translate into improved image quality.

More Detail: When two sensors of a different physical size have the same megapixel resolution, there will obviously be a difference in terms of the size of each photosite (pixel) within the sensor. A larger photosite translates into an ability to essentially capture more light. That, in turn, means that the difference between a “full” and “empty” photosite will be greater.

This results in greater potential dynamic range for the larger sensor, as well as reduced noise levels based on being able to capture more light.

Of course, there are many other factors that impact the final quality of the image, including many different factors related to an individual image sensor. Therefore, you can’t assume that a full-frame sensor will always offer better image quality compared to a smaller sensor size.

To be sure, greater resolution (as in more megapixels) can provide larger potential output sizes. And a larger image sensor has the potential to provide higher dynamic range and lower noise levels. Both of these can provide higher image quality, but the reality depends on the specifics of the sensor and image processing (both in the camera and after capture). This is why there is really no replacement for testing the output from different image sensors to determine the relative quality potential of each.

Today’s Question: Very recently when in the Develop module of Lightroom Classic, when I use the Adjustment Brush or the Graduated Filter, I can no longer see the circle with a black dot in the middle after making the adjustments. Usually when I hover the mouse over the dot, I can see the mask that was made during the adjustment. Has something changed in Lightroom Classic?

Tim’s Quick Answer: The edit pin icon you’re referring to is still available in Lightroom Classic, so the display must have been turned off. From the Show Edit Pins popup on the toolbar below the image preview you can choose “Auto” or “Always” to re-enable the display of edit pins.

More Detail: The targeted adjustment tools in Lightroom Classic (Graduated Filter, Radial Filter, and Adjustment Brush) use an edit pin to indicate where the adjustment has been applied within the image. You can click on an edit pin to select which targeted adjustment you want to refine, hover your mouse over an edit pin to see an overlay representing the shape of the area being affected by the adjustment, and press Delete after selecting an edit pin to delete a targeted adjustment.

You can choose when you want the edit pins to be displayed, which means it is possible to hide the edit pins altogether by selecting the “Never” option from the Show Edit Pins popup on the toolbar below the image preview in the Develop module. Note, by the way, that if that toolbar isn’t visible you can press “T” on the keyboard to bring it back.

I suspect in this case the keyboard shortcut for the edit pin display may explain why the edit pins unexpectedly stopped being displayed. You can press “H” on the keyboard to cycle through the options for the Show Edit Pins popup.

My preference, by the way, is to use the “Auto” option for the Show Edit Pins popup. This causes the edit pins to be hidden when you move your mouse pointer away from the image, so you can get an unobstructed view of the image. When you bring your mouse pointer back over the image (with the applicable targeted adjustment tool active) the edit pins will appear on the image again.

Today’s Question: It seems to me that most backup routines are primarily concerned with drive failure. I lost a lot of my photos because the individual photo files somehow got corrupted. What do you think is the best solution to prevent overwriting good files with files that have become corrupted? As I understand GoodSync, if a file on my data drive becomes corrupted, that corrupted file will be backed up to my backup disk and overwrite the good file. What is the best solution to prevent losing files in the case of file corruption?

Tim’s Quick Answer: This is actually a somewhat tricky issue to solve for, since it can be difficult to know when a file gets corrupted. It is possible that a corrupted file would appear as a changed file, and thus replace the good copy on a backup. A more traditional incremental backup solution would help, though such an approach can be a bit more complicated to restore from.

More Detail: The basic concept of backing up your data is rather straightforward. If anything should happen to a source file, you recover from a backup copy of that file. With a synchronization approach to backing up your photos, however, a corrupted original file may replace the good file on the backup, so that you no longer have a good version of the file to recover from.

With a synchronization backup the backup copy of a file will only be replaced if the original has changed. It is possible that if the source file is corrupted that will be detected as a change and thus the backup will also become corrupted.

Other incremental backup solutions provide a little more flexibility, by virtue of keeping track of incremental changes with each backup. Of course, if a file does become corrupted it is not very easy to recover since you won’t know how far back in your backup history you need to go to find the non-corrupted version of the file.

Fortunately, file corruption is not particularly common except in the case of failing hardware. This is especially true of raw capture photos, since most software will not make changes directly to the source raw files. However, it is always possible for files to become corrupted, and it can be difficult to have a backup solution that protects against this risk.

Performing regular scans to check for a corrupted file structure on your hard drive can help, such as with Disk Utility on Macintosh or System File Checker on Windows.

Today’s Question: How do you create a Preset for Importing which includes Len Correction when the lens may be different for different pictures?

Tim’s Quick Answer: You can use the “Auto” setting for Setup option for profile-based Lens Corrections to create a preset that will apply the adjustment properly based on the metadata for each image.

More Detail: Lightroom Classic enables you to apply profile-based corrections to photos based on the optical qualities of the lens that was used. That includes both distortion correction and vignetting correction.

To apply this adjustment to an image in the Develop module start by going to the Profile tab of the Lens Corrections section of the right panel. You can then turn on the “Enable Profile Corrections” checkbox and choose “Auto” from the Setup popup. At this point the appropriate profile should be selected below based on the metadata for the image, assuming there is a profile for the lens that was used.

If you want to include the profile-based Lens Corrections adjustment as part of a preset, I recommend using the “Auto” option for setup. This will enable the correction to be customized for each image. I use a preset with this profile-based lens correction as part of a Develop preset I apply at import, so that all images I import have this correction applied.

After applying this and any other desired adjustments to an image, you can click the plus symbol (+) to the right of the Presets heading on the left panel in the Develop module and choose Create Preset from the popup menu. In the New Develop Preset, turn on the checkbox for all adjustments you want to include as part of the new preset, such as the Lens Profile Corrections checkbox in this example. Enter a name for the preset at the top of the dialog and click the Create button to create the new preset.

That new preset can then be applied to any image, including to images upon import using the Develop Settings popup in the Apply During Import section of the right panel in the Import dialog.

Today’s Question: Why is a stitched panorama said to be preferable to a good wide-angle lens?

Tim’s Quick Answer: The two key advantages to a composite panorama compared to a wide-angle capture of the same general scene is higher resolution and less lens distortion.

More Detail: The overall perspective, or relationship between the various objects in a scene, is in large part defined by your distance from the scene. Therefore, if you photograph a scene from a given position, for the most part you will capture the same perspective regardless of the lens used.

In other words, you could either use a telephoto lens to extract a detail from a scene, or you could crop a wide-angle photo to extract the same detail, and the overall perspective will be the same for both images.

Of course, if you’re cropping a wide-angle photo rather than capturing the same scene with a telephoto lens, you’ll end up with fewer pixels in the cropped image. This addresses the first benefit of a composite panorama compared to a wide-angle photo. To over-simplify a bit, if a composite panorama consists of five frames, the resulting image will have somewhere around four times more pixels across compared to a wide-angle capture of the same scene, taking into account some overlap between frames for the composite panorama.

So, I would say that the primary reason to capture a composite panorama rather than a single wide-angle photo would be to produce an image of higher resolution. This enables the final image to be printed at a considerably larger size than the single wide-angle capture would allow.

In addition, wide-angle lenses generally have more distortion than lenses with a longer focal length. That means you can generally get an image that is more accurate with less distortion using a composite panorama technique as opposed to capturing a single frame with a wide-angle lens.

In some cases, a photographer may want to have the unique “distorted” view that can be created by a wide-angle lens. But when you want to avoid distortion and produce a final image that can be printed as large as possible, creating a composite panorama will help you achieve these goals.

Today’s Question: When you’re in a tricky outdoor white balance situation, do you use any special tools to determine white balance or do you just set your camera and try to make adjustments in post processing? I’m often not sure I’ve gotten it right in post.

Tim’s Quick Answer: You could use a custom white balance setting in the camera to ensure you are starting with color that is as close as possible to the actual lighting conditions, evaluating the results in the camera with a comparison to the scene before you.

More Detail: I typically use the “Auto” white balance setting in conjunction with raw capture, since it is then possible to fine-tune the color when processing the raw capture with no penalty in terms of image quality. That’s because the white balance setting is really just a metadata value and does not actually change the raw image data captured by the camera.

However, if you’re trying to ensure the colors are as accurate as possible, the Auto white balance setting is not necessarily the best option, as you would then need to make adjustments to the color in post-processing based on your memory of the scene.

To help ensure you’re getting a photo with the most accurate color at the time of capture, you could set a custom Kelvin value for the white balance on your camera. You could evaluate the setting with the Live View display, comparing it against the scene before you, or you could capture a test photo to compare to the scene. You could still fine-tune the color in post-processing, but you would be starting out with a photo that has more accurate color based on the lighting conditions of the scene you were photographing.

If you were dealing with a situation where you want the colors to be truly accurate, as though the scene were illuminated by perfectly white light without any color cast, you could use a custom white balance setting in the camera that involves capturing a reference image of a neutral object such as a blank sheet of paper or gray card. You could also use a more sophisticated approach such as using an X-Rite ColorChecker Passport (https://bhpho.to/3aXUlVx).

Today’s Question: A while back you answered a question about how to take multiple exposures of a scene, using Photoshop to blend images and produce a final image without the people who were moving around during the time the images were captured. This was new to me, but I have used neutral density filters and a long exposure to get the same result. It seems to me that using multiple images may be easier to set up and don’t require that you have a neutral density filter on hand, but otherwise is there any advantage to either of these methods?

Tim’s Quick Answer: I would say that capturing a series of images is a more dependable way of make sure that people (or other moving elements) do not appear in the final photo. A long exposure includes the risk that some moving objects won’t disappear completely, as well as the risk that the overall image may be blurry due to camera movement during the long exposure.

More Detail: One solution for making a subject moving across a scene magically disappear is to use a long exposure for that capture. Let’s assume, for example, that you photograph a scene with a 30-second exposure and that someone walks through that scene during the exposure. If it only takes the person a few seconds to walk through the scene, there will most likely not be any evidence of that person in the long-exposure photo.

That’s because the person represents such as short duration of the exposure in any area of the photo that they won’t appear in the image. If they were holding a flashlight or wearing highly reflective clothing, then they may of course produce a ghosted appearance in the image. But the idea is that long exposures can cause moving subjects to disappear from a photo.

However, this approach can be tricky. Not only might the person be illuminated enough to appear with a motion blur across the photo, but sometimes a person or object that is moving through the frame doesn’t move fast enough to completely disappear.

In addition, with a long exposure you have the risk of camera movement causing blur, even if you’re using a tripod. For example, there may be vibrations imparted by a passing vehicle, or the wind might be strong enough to move your lens during the exposure.

Therefore, I find the approach of capturing multiple photos of the scene and then blending the images in post-processing (primarily using Photoshop) provides a better solution. And the blending of those photos can be automated rather easily in Photoshop using the technique covered in an earlier Ask Tim Grey eNewsletter, which you can review here:

https://asktimgrey.com/2020/05/22/automatically-remove-people/