Ask Tim Grey

Today’s Question: When exporting some photos from Lightroom Classic recently, I noticed that there was a checkbox to the left of each preset name on the list, which I hadn’t seen before. I’ve always just clicked the name of the preset to select it. Am I supposed to turn on the checkbox instead? Why are there two ways of choosing a preset when exporting photos?

Tim’s Quick Answer: The checkboxes associated with presets in the Export dialog are a relatively new addition, and they enable you to export images using multiple presets at a time.

More Detail: If you export images for a similar purpose somewhat frequently, it can be very helpful to save a preset with the settings for the export to streamline the process. With a preset the process of exporting photos is as easy as selecting the photos, clicking the Export button at the bottom of the left panel in the Library module, choosing the preset, and clicking the Export button to initiate the export.

Thanks to the checkboxes, you can also export photos for more than one preset at a time. For example, you might export photos to share to social media and to submit for a photo contest, with each of these calling for different specifications for the pixel dimensions and other settings. To export for more than one preset you simply turn on the checkbox for all the presets you want to export for, and then click the Export button.

So, if you’re exporting for just a single preset, you can just click the name of the preset in the Export dialog and then click the Export button. If you’re exporting for multiple presets, you can turn on the checkbox for each of those presets and then click the Export button.

Today’s Question: You wrote: “Whenever you enlarge a photo you are degrading image quality to some extent.” I think this was also true in my film days, which is why I bought a “Portrait Lens.” Could you comment and compare film and digital?

Tim’s Quick Answer: There is indeed a degree of image degradation when enlarging either an analog (film) or digital image. However, film did have bit of an advantage in this context by virtue of being a format that was analog in nature, without having discrete pixel values as is the case with a digital image.

More Detail: It’s a bit of an oversimplification, but you can think of the process of enlarging an analog image as projecting the image at a larger size. For example, if you project a film slide with a projector, you can create a larger image by simply moving the projector farther from the screen you’re projecting onto.

Of course, there is still some degradation, such as the image appearing less sharp the more you enlarged it. But the fidelity of the image would be retained very well due to the analog nature of the original.

While digital capture provides a variety of advantages, it does introduce some challenges when it comes to enlarging the image. Rather than simply projecting the image onto a larger screen you effectively need to add pixels to the image. This is done by calculating the color values for new pixels based on the color values of surrounding pixels. You’re basically spreading the existing pixels out and then adding new pixels in between. This causes a loss of sharpness and a degree of lost color fidelity.

It is important to note that today’s digital cameras have exceeded the capabilities of most film cameras in terms of resolution and color fidelity. Even with the theoretical advantages of film in terms of enlargement, I would say that today’s digital cameras produce images that can be enlarged with greater quality that what was possible with film due to the inherent limitations involved and the improvements in technology with digital.

It is difficult to compare older technology with newer technology, but in general terms it is fair to say that there are differences in how enlargements were degraded between film and digital captures. There are similarities and differences with both, and of course differences depending on the level of technology for the different capture formats being compared.

Today’s Question: You said that “the future of photography is definitely mirrorless”, but does that mean you think at some point manufacturers will stop making digital SLR cameras?

Tim’s Quick Answer: Yes. I completely expect virtually all new cameras to be mirrorless in a relatively short period of time, most likely by the end of this decade.

More Detail: The way I look at this situation is to imagine a scenario where technology is in exactly the same state as it is right now, except that the camera hasn’t been invented yet. If that were the case, what are the odds that an inventor would add a mirror to a camera they were designing? I would say those odds are very low.

The primary reason to have a mirror in a single lens reflect (SLR) camera is to enable the viewfinder to provide a view through the lens, rather than the offset view provided by previous cameras due to the viewfinder being completely separate from the lens.

A mirrorless camera provides the same general functionality without the use of a mirror, by projecting the live image from the image sensor to an LCD display on the back of the camera or to an optical viewfinder that is essentially a very small LCD display that you hold your eye up to.

The earliest models of what led to today’s mirrorless cameras featured an electronic viewfinder (EVF) of relatively low quality, which greatly reduced the utility of these cameras. Now we have EVF displays of exceptional quality, so that you really aren’t giving up anything by not having an optical viewfinder.

In addition, mirrorless cameras provide a variety of benefits beyond simply making up for the lack of an optical viewfinder. We’re already seeing more new models of mirrorless cameras and fewer new models of digital SLR, and I expect that trend to continue until virtually all cameras are mirrorless.

I mean, I’m sure there might be some niche manufacturers out there who continue making cameras with mirrors, but these will be the exception rather than the rule.

Today’s Question: There is a mass shift in photography equipment to mirrorless. Am I really sacrificing anything in continuing to shoot with my old Canon 5D III DSLR?

Tim’s Quick Answer: If your current digital SLR camera is meeting your needs, I don’t think there’s any need to switch to mirrorless, just as there wouldn’t be a need to upgrade to a newer digital SLR.

More Detail: There has indeed been a tremendous shift in photography from an emphasis on digital SLR cameras to mirrorless cameras. The future of photography is absolutely mirrorless, but that doesn’t mean you need to feel rushed to buy a mirrorless camera to replace a digital SLR you’re happy with.

There are advantages on both sides when it comes to mirrorless versus DSLR. To be sure, mirrorless does generally offer some advantages over DSLR cameras in general, such as often providing smaller and lighter cameras and lenses, some advanced autofocus technology, and features such as focus peaking and a live histogram right through the viewfinder, among others.

However, mirrorless cameras also generally perform worse in terms of battery performance, and still don’t offer as many options in lenses compared to digital SLRs. For photographers with existing DSLR cameras and lenses, there is also the obvious switching cost of potentially changing camera systems by virtue of switching to mirrorless.

For a photographer who is buying their very first camera, I would suggest that mirrorless is the better option in large part because it does represent the direction photography is clearly headed. For a photographer who currently has a digital SLR, my suggestion is to make a decision based on whether the advantages of a mirrorless camera system are meaningful to you, taking into account the cost involved in switching camera systems.

Photography is about the photographer first and foremost. Great pictures can be made even with a camera that isn’t trendy or doesn’t include all the latest and greatest features.

Today’s Question: I was advised long ago that it is best to enlarge and then crop because the result is better than if you crop and then enlarge. What are your thoughts on this?

Tim’s Quick Answer: The order of cropping versus enlarging doesn’t make a significant difference in image quality, so I recommend using the approach that is most convenient in your workflow. That generally means cropping before resizing, because you would typically crop the master image and then only resize when preparing a derivative image for output.

More Detail: In general cropping involves simply removing pixels from the outer area of an image. In this context, whether you enlarge before or after cropping won’t make any difference in terms of image quality. I’ve heard arguments about there being a potential benefit to leaving the pixels in place until after resizing so that all pixels are available for the software that is calculating the pixel values for resizing. That is an incredibly marginal issue in my view, and would only affect pixel values at the very outer edge of the cropped image.

If you rotate as part of the crop then you are altering the pixels in that process. Enlarging before cropping and rotating would ensure that you’re enlarging based on unaltered pixels, but the reality is that you’re performing two alterations (enlarging and rotating) and there is no significant difference in the results from the standpoint of image quality.

Therefore, I don’t recommend making a point of performing the steps of enlarging and cropping in a particular order, other than based on what is most convenient for your workflow. In general, there’s no need (nor any reason) to resize the master image until you’re preparing a derivative copy of that image for output such as printing. That often means the image will have been cropped before it is resized for the final output, but it is perfectly fine to perform those steps in any order.

Today’s Question: Does Enhance in Lightroom Classic or Topaz Gigapixel help in terms of enlarging an image rather than purchasing a lens with a longer focal length?

Tim’s Quick Answer: Today’s advanced tools for enlarging digital images are certainly impressive, but in my view it is still best to enlarge the image by getting closer to the subject or by using a lens with a longer focal length.

More Detail: Whenever you enlarge a photo you are degrading image quality to some extent. That’s because software needs to add pixels to the image, effectively putting new pixels in between existing pixels that have been spread out to produce a large image. While the algorithms used for this purpose are incredibly sophisticated, the process does cause some degree of loss of sharpness and quality in the image.

Therefore, while software such as Topaz Gigapixel or the Enhance feature in Lightroom Classic are excellent solutions for enlarging an image, when the aim is to have a subject fill a larger portion of the frame this isn’t the best solution.

In effect, enlarging the subject involves cropping so the subject represents a larger portion of the frame and then enlarging to the intended output size. Instead of cropping after the capture and resizing, you could simply crop at the time of capture so that less enlargement is necessary (or perhaps no enlargement is needed at all).

To increase the size of the subject we are photographing within the frame we could simply get closer to the subject. If you cut the distance to the subject in half, the relative size of the subject in the frame would double. Of course, moving closer to the subject would also alter perspective within the frame, which may not result in the composition you prefer. If so, using a longer lens focal length provides a solution.

If you double the lens focal length you would also essentially double the relative size of a subject in the frame. This would enable you to maintain the desired perspective for the scene, since you could stay in the same position. Of course it also means generally purchasing a more expensive lens.

To be sure, you can most certainly get very good results from cropping and then enlarging an image, especially with some of the more advanced enlargement tools available in today’s software. However, you’ll maintain better image quality by not needing to enlarge as much. Therefore, getting closer to the subject or using a longer lens focal length are the best options for having the subject take up more space in the frame at the time of capture, rather than having to crop and then enlarge the image in post-processing.

Today’s Question: Does cropping an image in Photoshop, and especially cropping multiple times, degrade the quality of the image?

Tim’s Quick Answer: While aspects of cropping in Photoshop can be performed non-destructively, if you rotate or resize as part of the crop that will slightly degrade the image. Rotating or resizing by cropping multiple times would compound that issue.

More Detail: Today’s question was a follow-up to a recent question about cropping multiple times in Lightroom Classic. As I noted in my answer to that previous question, there is no degradation in image quality caused by adjusting the crop settings multiple times in Lightroom Classic. In effect, only the final settings that are established when you export or otherwise share the image count, as though you had only made one change to the crop settings. This same concept applies when making multiple updates to the crop setting when processing a raw capture in Camera Raw.

In Photoshop things are a little more complicated because you are working on actual rendered pixels rather than a raw capture that has not yet been full processed and rendered.

You can use a non-destructive crop in Photoshop by making sure the “Delete Cropped Pixels” checkbox is turned off on the Options bar when using the Crop tool. When this checkbox is turned off the pixels you crop won’t actually be deleted from the image, but instead will be hidden outside the image canvas area. You could later reveal those cropped pixels by choosing Image > Reveal All from the menu.

However, it is also possible to resize and rotate an image as part of the crop in Photoshop. Those adjustments would alter the actual pixels in the image, which causes at least a minor degradation in image quality. If you resize and rotate multiple times by cropping multiple times with the Crop tool, that degradation will be amplified.

It is important to note that the degradation in image quality here would generally be very minor and difficult to see in the image. I think it is also important to keep in mind that rotating to fix a crooked horizon, for example, is more important than avoiding the very minor degradation in image quality that the rotation might cause.

Considering all the above, however, if I realized I didn’t get the image rotated perfectly with the first crop in Photoshop, I would prefer to undo that crop and apply a new crop with a better rotation setting, just to try to preserve image quality as much as possible.

Today’s Question: I process all my RAW files to DNG when I download them. I would like to revert some of my old files to the original DNG without edits. How do I do I revert the file?

Tim’s Quick Answer: You can revert the DNG to the original default settings by using the Reset option in either the Develop module in Lightroom Classic or in Camera Raw if using Photoshop. Also, as long as you had enabled the option to embed the original raw capture in the DNG file, you can extract the original raw capture using the Adobe DNG Converter.

More Detail: An Adobe DNG file behaves essentially the same as any other raw capture format, in terms of being able to apply adjustments with software such as Lightroom Classic or Camera Raw (in Photoshop). With raw processing software you can reset the settings back to the defaults. In Lightroom Classic you can reset the adjustment settings by clicking the Reset button at the bottom of the right panel in the Develop module. In Camera Raw you can hold the Alt key on Windows or the Option key on Macintosh, which will cause the Cancel button to change to a Reset button. Simply click the Cancel button while holding the Alt/Option button to reset the adjustment settings.

If you embedded the original raw capture in the DNG upon conversion to DNG, you can also extract that original raw image, which won’t have any adjustments applied to it. The free Adobe DNG Converter software can be used to extract the embedded raw capture.

After launching the Adobe DNG Converter, click the Extract button at the bottom-center. In the dialog that appears first select the folder containing the images you want to extract the raw captures from in section one. Then select the destination folder for the raw captures in section two. Click the Extract button to process the images, extracting the raw captures to the designated folder.

You can download the free Adobe DNG Converter from the Adobe website here:

https://helpx.adobe.com/camera-raw/using/adobe-dng-converter.html

Today’s Question: As a follow-up to the question about browsing only the photos in a parent folder [in Lightroom Classic] is there a way to browse the photos in only the several subfolders without seeing the photos from the parent folder? Sort of the opposite of the option to not show photos in subfolders?

Tim’s Quick Answer: You can easily browse only the photos in a group of subfolders without seeing the images from a parent folder by simply selecting the multiple subfolders within the Folders list in Lightroom Classic.

More Detail: Selecting multiple folders in Lightroom Classic is quite simple, but I find it is a feature that many photographers overlook. You can select a group of folders within the Folders list in the Library module in Lightroom Classic in the same way you can select multiple files or folders through your operating system.

For example, if you want to browse the photos within several folders in a range, you can click on the first folder in the range and then hold the Shift key on the keyboard while clicking the last folder in the range, and all folders within that range will be selected.

You can also toggle the selection of multiple folders that are not in a contiguous range using the Ctrl key on Windows or the Command key on Macintosh. While holding the Ctrl/Command key and clicking on a folder, the selection status of that folder will change. So, for example, if you had selected a range of five folders and then held Ctrl/Command while clicking on the middle folder, only four folders (the first two and last two) would be selected.

Once you’ve selected multiple folders you will be browsing the photos in all of those folders. You can even use the filter criteria on the Library Filter Bar to only view photos that meet specific criteria within the selected folders. Note, by the way, that these same options are available for selecting collections in addition to folders.