Have you ever asked yourself what the best focal length for your first (or your next) prime lens should be? If you use mostly zoom lenses, Adobe Lightroom may be able to help.
In Lightroom, select the top folders containing all your pictures. Then open the Grid view in the Library module and select Metadata in the Library Filter bar on top of the grid. This will show you a couple of columns with selected metadata that you can filter for.
Next, you might have to change the displayed metadata by clicking on a column’s header. In the end you should have one column displaying the lens model, and a second column displaying the focal length like in the screenshot below.
From the list of lenses, select a lens with a broad zoom range that covers typical focal lengths—typically your most used everyday lens. In the example here, I have chosen the Canon EF-S 15-85 mm IS USM, which is a great general purpose lens for APS-C crop cameras.
In the column displaying the focal lengths you see how many pictures were taken at which focal length for the selected lens; in my example, we see a few focal lengths that are assigned to a significant higher amount of pictures than other focal lengths.
Naturally, the lower and the upper end of the focal length range can be ignored. You hit the lower end each time you want to have more on your picture and would have needed an even wider lens; however, it was not available at your hand at that time or you just might have been too lazy to change the lens. Same for the upper focal length, where you would have zoomed in more, if more focal length would have been available.
Ideally, you would do this test with a lens that offers a focal range like 8-500mm… if this lens existed.
To visualize the distribution of used focal lengths with the selected EF-S 15-85mm I’ve created a chart that omits the lower and upper ends of the focal length range:
As you can see there are three obvious spikes at 24mm, 35mm, and 50 mm. Coincidentally (or not?) these are standard focal ranges for prime lenses. However we are still talking about APS-C, so let’s convert these focal lengths to their full frame equivalents:
So at full frame we see spikes at the most popular focal ranges I use are:
- 35mm, which is the standard focal length for street photographers.
- 50mm, which is considered as the perfect normal focal length and the focal length of the most popular prime lens, the nifty fifty.
- And, finally, 75mm, which is close to 85mm as a flattering focal length for portraits.
Still coincidence? Maybe not.
As a last step, click on the focal length you want to examine more and Lightroom will show you what kinds of pictures you’ve taken at this focal length.
Depending on your shooting style, your distribution of used focal lengths might look different than mine. That’s the point. It will help you determine the focal lengths you use most—a good candidate for your first (or next) prime lens.
About the author: Carsten Schlipf is a German software developer and amateur photographer. You can find his work and more of his musings on photography on his website. This post was also published here.