Mirror Lenses


Today’s Question: I am sorry, but what is a mirror lens? It is a term and an item I have never come across, in film photography or in digital. Are there any such lenses currently available?

Tim’s Quick Answer: A mirror lens (also called a reflex lens or catadioptric lens) is a lens that employs a convex mirror in place of one or more lens elements. These lenses were smaller and lighter than the more common models, but they don’t offer an adjustable lens aperture, and out of focus areas could create circular artifacts that many photographers found objectionable. Mirror lenses are still available from some manufacturers, such as a 500mm model from Opteka you can find here: https://amzn.to/2QNoNqE

More Detail: When I mentioned mirror lenses in a previous Ask Tim Grey eNewsletter about bokeh, the thought crossed my mind that some readers may not be familiar with these lenses. It also made me realize I might be perceived as a “dinosaur” for making the reference. After all, these lenses were most popular in the 1970’s and 1980’s.

Mirror lenses are commonly used in telescopes, and have also been available as photographic lenses. Many mirror lenses for photography were telephoto, because that is where the key advantage of a mirror lens has the greatest impact. Because a convex mirror is used in place of one or more lens elements that would generally be made of glass, a mirror lens can be significantly lighter (and smaller) than a “conventional” photographic lens.

However, mirror lenses also have some issues that contributed to their lack of popularity today. As noted above, there is no adjustable aperture on a mirror lens. That means you can’t adjust the depth of field with a mirror lens. In addition, if the shutter speed doesn’t provide enough control over the exposure, you may need to add a neutral density filter.

In the context of out of focus areas (as noted in my previous answer about bokeh), mirror lenses can produce ring-shaped artifacts that many photographers found distracting and undesirable. In other words, while a conventional lens would result in bright highlight artifacts in the shape of the lens aperture, a mirror lens would create “donut” shaped highlight artifacts.

So, mirror lenses do have some advantages, but I would say the disadvantages are more significant, which is why they are not in common use by photographers today.

Bokeh Perspectives


Today’s Question: Much has been written since the term “bokeh” was first introduced 20 years ago. As I understand it, it is based on the design of modern lenses to create a certain effect of the background or shadow. Photography has been around far longer that 20 years. What is your take of the artistic element of bokeh? Is it a real compositional element or just another device by the techies in our art.

Tim’s Quick Answer: I think of the bokeh quality of a lens as an additional creative decision the photographer is able to make. Sometimes you might choose a specific lens because of the bokeh quality (or other behavior based on specific lens attributes). In other cases, that bokeh may simply be a “side effect” of other intentions you had as a photographer.

More Detail: In many respects “bokeh” is just a fancy way of describing the visual appearance of out-of-focus areas of a photo. In particular, when photographers refer to bokeh they are often referring to how relatively bright highlights in out-of-focus areas are rendered, which in turn is impacted by the shape of the lens aperture.

There are many reasons you might choose a particular lens for a given photographic situation. For example, you might choose a lens with a short focal length because it has a wide field of view. Coincidentally, that same lens might have a lens aperture with nine blades, but that might not have any effect on the photograph you are currently capturing.

In other cases, the fact that there are nine blades on the lens aperture for a given lens might be the specific reason you choose to use that lens for a given photo. For example, when including the sun in the frame I typically opt for a lens with an odd number of aperture blades so I get a sunburst effect with more rays than I would using a lens with an even number of aperture blades.

To me the bokeh quality of a lens is similar. Some lenses have very pleasing bokeh quality, and others render out-of-focus areas in a way you might be indifferent about. In other words, sometimes you might not be all that concerned about how blurred areas of the scene will look. In other cases you might want to choose a specific lens based on how the background will appear.

I think a good example here would be a mirror lens. Many photographers find they do not like the way out-of-focus areas are rendered with a mirror lens, so they might avoid such a lens altogether, or at least for certain situations. This is the type of creative decision you might make about which lenses to buy and which lens to use in a specific scenario, based on the bokeh quality of that lens.

So, while the term “bokeh” may get a little over-used, and might seem a bit cliché, I do think it is worth being familiar with how a lens will render out-of-focus areas. In other words, as always it is important to understand your equipment, so you can anticipate the results you’ll get, and so you can choose the best gear for achieving your photographic vision.

Finding Photos by Location


Today’s Question: I’ve been geotagging my shots for three years, and now I need to find one photo among scores of folders in my Lightroom catalog. I know exactly the intersection at which I shot this photo. Is there a quick way to locate all pictures within a block or two of that point?

Tim’s Quick Answer: You can locate photos based on location very easily in the Map module within Lightroom. For example, you could browse the “All Photographs” collection, and then navigate to the applicable location on the map in the Map module to locate the specific photo you’re looking for.

More Detail: When you want to find photos based on their map location, the first step is to make sure you are browsing the group of photos that includes the photo you’re looking for. For example, if you knew which folder the image was located in, you could navigate to that folder. If you’re not sure where the photo is located, simply choose the “All Photographs” collection in the Catalog section at the top of the left panel in the Library module.

Next, switch to the Map module and navigate to the position on the map where the photo you’re looking for was captured. Note that you can use the Search field at the top of the toolbar above the map to help you more quickly navigate to a particular location on the map.

You can then zoom in to the specific area on the map where the photo was captured. The pushpins on the map will indicate the number of photos in each location, and you can click a pushpin to view the photos in that location. You can also choose the “Visible On Map” option on the toolbar above the map so the Filmstrip will only show thumbnails for photos that have location information for the current map area.

Once you’ve found the photo you’re looking for, you can right-click on the image on the Filmstrip and choose “Go to Folder in Library” to navigate to the folder that contains the image you were looking for. You could then turn off (or change) the filter settings as needed to help you locate other photos captured at around the same time.

Metadata for Raw


Today’s Question: You said: “That means that by using keywords (and saving metadata for my photos out to the actual files on my hard drive) I can still have access to that information even outside of Lightroom [or Photoshop].” Would this apply to RAW files?

Tim’s Quick Answer: Yes, Lightroom is able to save standard metadata (including keywords) to raw captures as well as other image file formats (such as JPEG and TIFF). The difference is that the metadata is written to an XMP “sidecar” file in the case of a raw capture, compared to the actual image file for other file formats.

More Detail: Today’s question is a follow-up to a previous answer related to saving metadata to the actual files, rather than only in the Lightroom catalog. I had indicated that saving metadata to the actual image files provides a backup of most of the information in your Lightroom catalog, and also makes it possible to view your metadata with other applications (such as Adobe Bridge).

Lightroom can save metadata to files for all supported image formats. The only difference is where the actual metadata is saved. For “standard” image file formats (such as JPEG, TIFF, and even Adobe DNG), the metadata updates will be written to the image file itself. For proprietary raw capture formats, the metadata will instead be written to an XMP sidecar file.

It is important to keep in mind that all metadata from Lightroom is not saved to the image files when you use the “Save Metadata to Files” command from the Metadata menu (or enable the automatic writing of metadata in the Catalog Settings dialog). Lightroom-specific features such as pick and reject flags, collections, and virtual copies will not be saved to the image files.

Only standard metadata values and the Develop adjustment settings are saved when you use this option. That said, I’d rather have most of my information backed up and available to other applications, as opposed to having that information only available in the Lightroom catalog.

Multiple Catalogs


Today’s Question: You say ONE catalog is best [in Lightroom Classic], but I am struggling with this due to my personal situation. I am wondering if it would be better for me to have three catalogs. One would be for personal photos, one for my business (including events from the school), and another for stock photos. Is that crazy to do? If you still think I should only keep one catalog for everything, how would I keep that organized in Lightroom? Would you suggest setting up some sort of Collection structure? I would love your opinion on my situation.

Tim’s Quick Answer: In this particular scenario (and in fact for most scenarios) I would still recommend using a single Lightroom catalog for all photos. You can then use a folder structure, unique keywords, or collections (or a combination of all of these) to help keep your photos organized by categories.

More Detail: The reason I prefer (and recommend) using a single catalog for all photos to be managed by Lightroom is that it streamlines the process of actually locating photos when you need them. In other words, when you need to find a photo, you simply launch Lightroom to get started, without having to figure out which catalog the particular photo might be in.

When a photographer feels that they need to have multiple catalogs, there is generally a solution that enables them to maintain the ability to filter photos by different categories, while still streamlining their workflow by having a single catalog.

For example, you could create parent folders that represent those categories. In the case of the scenario outlined in today’s question, for example, you could create master folders for “Personal”, “Business”, and “Stock”. When importing photos, an appropriate folder could be created within the applicable master folder for the photos being added to the catalog.

You could also use what I refer to as “fake” keywords, meaning keywords used for a purpose beyond the “standard” approach. This could include a keyword based on the category for each photo. I prefer to identify the keywords as being unique in this context, so I might use a category-based keyword of something like “CATEGORY-Personal” as that keyword.

Collections can also be used for this purpose, potentially with category-based collection sets, which could contain individual collections for the photos you want to manage in this way. The one caveat I recommend considering when it comes to collections is that they only exist within the Lightroom catalog. If for any reason your catalog was lost or you decided to switch to different software for managing your photos, the collections would likely be lost. Keywords, on the other hand, could be preserved.

The point is that Lightroom provides a variety of ways to organize your photos, and I feel it is best to make use of those various options rather than dividing photos into multiple catalogs.

Cloud Backup Strategy


Today’s Question: What do you think about offsite cloud storage for backing up the laptop computer with home back up drive?

Tim’s Quick Answer: I think a cloud-based backup solution can be a very good supplemental backup solution, with a few caveats. Good options include Backblaze (https://www.backblaze.com) and Carbonite (https://www.carbonite.com), among other options.

More Detail: Among the key aspects of a good workflow strategy is that you retain multiple copies of your important data (such as photos), and that you store a backup at a separate physical location from your original data. An online (cloud-based) backup solution can help meet both of these goals.

Of course, an online backup solution isn’t without its challenges. To begin with, you don’t have any control over the storage being managed by the company providing the online backup service. In most cases you won’t even have any idea where the computers storing your online backup are actually located.

In addition, by its nature an online backup solution requires an Internet connection for your ongoing backup updates. As you add or update files, the backup will update via your Internet connection. Thus, if you add or update files (especially large files) on a regular basis, the actual backup update can take considerable time if you don’t have a fast Internet connection.

It is also worth noting that while many online backup services offer unlimited backup data storage, in some cases when you reach a certainly threshold your connection (and therefore your backup) may slow considerably. If the delay in backing up your latest data is significant, you could find that you are missing recent files in the event you need to recover from an online backup.

For these (and other) reasons, I recommend only using an online backup as a supplement to a complete backup solution. In other words, I recommend having at least two full backups of your data (plus the source data that is being backed up), in addition to any online backup you choose to make use of. I also recommend storing at least one of your backup copies at a separate physical location from the source data, even if you’ll use an online backup solution.

Ultimately, that means an online backup solution would provide a non-critical backup that serves to provide additional peace of mind at a relatively modest price. But I would never recommend using an online backup service as your only backup solution.

Avoiding Lens Flare


Today’s Question: You talked about how you could figure out where lens flare would be positioned in a photo [in a recent Ask Tim Grey eNewsletter]. But how can I avoid lens flare altogether?

Tim’s Quick Answer: To avoid lens flare you need to ensure that the source of light causing the flare (such as the sun) is positioned behind the front lens element, or outside of the field of view of a lens shade. It is also possible to avoid (or minimize) lens flare by creating a composite image.

More Detail: Lens flare is caused by having a bright light source reflecting back and forth among the lens elements in a lens. A common cause of lens flare that is difficult to avoid, for example, would be having the sun in the frame of a photo.

You can mitigate the appearance of lens flare by changing your position, as noted in a previous Ask Tim Grey eNewsletter. Changing the zoom setting and lens aperture setting can also alter the lens flare, helping to minimize the adverse impact of the flare.

The best way to ensure there is not any lens flare in your photo is to ensure that any bright light source is behind a line parallel with the front lens element. In other words, having the sun more or less behind your position as the photographer. In addition, with the use of a lens hood, you can ensure the light source is outside the field of view of that lens hood, so that the hood effectively shades the front of the lens relative to the position of the light source.

Obviously either of the above approaches don’t provide ideal solution when then intent is to include the light source in the frame. In those cases you could create a composite image to minimize (or eliminate) lens flare in a photo, while still including the sun in the frame.

The approach involves first capturing the scene as you normally would, with lens flare included in the photo. Then capture a second capture of the same scene (ideally using a tripod to ensure the framing of both photos is a perfect match). For this second capture, use some object (such as a finger) to block the sun. This photo will not include any (or much) lens flare.

You can later combine the two photos into a composite, replacing the areas where lens flare is visible with the same areas from your second photo. This approach can alter the overall appearance of the image when there is scattered backlighting, for example, but does provide an effective means of minimizing lens flare in a photo.

Tone Curve Modes


Today’s Question: When I switch between the two presentations [parametric and point curve] for the Tone Curve in Lightroom at the bottom left is the title “Point Curve”. Should the title change to parametric when I am in the parametric mode or does it constantly stay as Point Curve? When I get the four sliders at the bottom, is that the parametric curve function or am I still in point control?

Tim’s Quick Answer: When you see the four sliders below the Tone Curve, you are in parametric mode. When you don’t see those sliders you are in point curve mode. These two options simply provide different ways to interact with the Tone Curve adjustment.

More Detail: The curve is always defined by points “behind the scenes”. In other words, the shape you’re defining is a series of Bezier curves, which require points to define the various changes in the shape of a curve. For example, an “S” curve can be defined by two points in addition to the end points. A simple arc could be defined with one extra point (in addition to the end points).

So, in a sense, you are always working with a “point curve”. And you always have the preset curve shapes available from the Point Curve popup regardless of which mode you’re currently working in.

The only difference between working in point curve versus parametric mode is how you interact with the curve. In point curve mode you are actually adding or moving anchor points directly on the curve. In parametric mode you are instead working with sliders (Highlights, Lights, Darks, and Shadows). Note, by the way, that you can still use the curve directly to adjust the slider values (by clicking and dragging directly on the curve), but you aren’t able to actually add or move anchor points directly in this mode. The sliders are simply intended to make it easier to manipulate the shape of the curve to achieve the desired effect in the photo.

Ultimately you are always refining the shape of the curve in order to change the appearance of the photo. The only question is how you are interacting with the curve. You can use the more simplified approach of using four sliders, or you can create and adjust multiple anchor points directly on the curve. The former is simpler, and the latter provides more control.

Website or None?


Today’s Question: With many other ways for a photographer to represent their work online, do you think it is important for photographers to have an actual website? Or would just social media pages or other outlets suffice?

Tim’s Quick Answer: While having a website is certainly less important than it might previously have been, I still think a website in some form can be useful to serve as a virtual business card for the photographer interested in promoting their photographic work. A very simple solution would be to use a platform such as Wix (https://timgrey.me/wix).

More Detail: The whole concept of a website has changed a bit, I think. What I mean by that is that many photographers can simply use a Facebook page or Instagram account as the foundation of promoting their photography. However, I do think there is value in having a central information point that is easy to point others to. A custom website address provides a good solution, in my view.

Many photographers simply use a Facebook page as a replacement for a website. And Instagram provides a platform for sharing your photography. For example, you can find (and like) my Facebook page at:


But if someone doesn’t use Facebook, I can redirect them to my Instagram feed, suggesting they follow me at @timgreyphoto. But if they aren’t an Instagram user, then what?

That’s why I think a single “landing page” with links to all of your applicable pages and content makes the most sense. This provides a simple and universal way to direct people to information about you and how to contact you.

For example, I maintain a simple website at http://www.timgreyphoto.com that exists simply to provide a central repository for the various information about me and ways to follow or contact me.

Having your own website doesn’t mean you need to hire a website developer or go to a lot of trouble. There are many platforms that enable you to create a customized website complete with your own custom website address. A couple good options for this type of site include Wix (https://timgrey.me/wix) and SquareSpace (https://www.squarespace.com).

Presets Disappeared


Today’s Question: What happened to the “Classic” Presets in Lightroom Classic 7.5 [for the Develop module]? There used to be a pretty extensive list of so-called “Classic” presets that included the AI-based Auto Toning feature that evaluated each image and applied auto toning.

Tim’s Quick Answer: The “Classic” presets have been hidden but are still available. You can right-click within the Presets area of the left panel and choose “Manage Presets” to bring up a dialog that enables you to choose which presets to display.

More Detail: The presets in the Develop module were re-organized with a recent update to Lightroom. This caused some third-party presets to be lost, requiring that they be re-installed. It also caused some of the categories of presets to disappear, but they are still available.

To modify the list of presets, start by right-clicking in an empty area within the list of presets on the left panel in the Develop module. On the popup menu that appears, choose the “Manage Presets” command. This will bring up the Manage Presets dialog, which lists the categories of presets available.

In this case you’ll notice the checkboxes for the preset categories beginning with “Classic” are turned off. You can turn on the checkbox for any of those categories that you’d like to still have available on the Presets list. Then click the Save button to close the Manage Presets dialog, and the Presets section will now reflect the selected categories of presets.