Shooting HDR Photos with a Drone & Quickly Editing Images
What is HDR? Why would I need to use it?
HDR stands for High Dynamic Range. The dynamic range is the difference between the lightest highlight and the darkest shadow in a photo. In certain lighting scenarios, usually during sunrise or sunset or shooting directly into the sun, no matter what your camera settings are, it is impossible to avoid having blown out highlights or completely black shadows. One solution for this is taking several photos at different exposures and compositing them together to make one, evenly exposed photo. Check out these examples from a commercial real estate shoot we recently completed in Draper, Utah.
How do I shoot HDR?
First thing’s first, always make sure your drone is set to shoot in manual, and it is taking RAW photos. Now we have a couple of options to choose from, depending on how much control you want to have over the final product.
1. The first option is to set your shooting mode to HDR. This is the simple and easy way to get a quick HDR photo. Your camera will automatically take bracketed photos and combine them into one HDR photo every time you click the shutter. But with this mode, you have no control over the processing of the image, you only get one already processed photo to work with, and not all drones have this option.
2. The next option is to have the camera take several bracketed photos at different exposures and process them into HDR photos later on. To do this, change the shooting mode to “AEB,” which stands for Auto-Exposure Bracketing. This makes your camera take take 3 or 5 photos in quick succession at varying exposures every time you click the shutter. These photos will be processed later on to make one HDR, and you can fine-tune each of the photos as you process them. The only issue with this option is that you cannot change the different exposures that your camera takes in AEB mode, it will automatically choose to take a photo one step above or below the correctly exposed photo.
2. The other option is to take several single-shot photos without moving the camera and manually change the exposure between each one. This allows you to decide how much to change the exposure between photos and gives you the most control over the final outcome. But manually changing the exposure increases the time between photos, and the longer the time in between photos, the higher the possibility of the camera moving, which can cause distortion in post-production. This is usually only necessary when there is a really large difference between the shadows and highlights in a photo and AEB mode cannot capture it all.
I recommend using the second option. AEB mode is very helpful because it captures several photos very quickly, eliminating a lot of movement between the photos, and in most lighting scenarios, it it able to get a large enough range of exposures to correctly expose for both the shadows and the highlights. This method gives the photographer enough control of the situation to get a good result, but also takes advantage of some of the drone’s automated functions that can help to eliminate human error.
How do I combine these photos into one HDR photo?
There are many different ways to process these photos into an HDR photo, but the most common programs used are Photoshop and Lightroom. Other programs include Photomatix, EasyHDR, Aurora, or many others, but each of these require a subscription and can get pretty expensive. Some programs that claim to “create stunning HDR imagery” just throw a filter on a regular photo and call it an HDR. I’ve found that the most reliable programs to merge HDR photos are Photoshop and Lightroom.
Import the photos into Lightroom. Select all 3 (or 5) and right click. Select “Photo Merge,” then “HDR…” and a dialog box pops up.
There isn’t a huge amount of options in this box, but there are a couple worth noting. The “Auto-Align” option can correct any small movement of the camera between the photos. Toggle the “Auto-Tone” option on and off to see which one you like better. If you don’t love what Lightroom comes up with, you can always edit the photo further after processing it.
Next, there are a couple options for deghosting. This can correct any movement of the subject of the photo. For example, in this photo, cars were driving across the bridge and shifted slightly between photos. The first photo has no deghosting, while the second photo has the highest amount. As you can see, the top photo has some blurriness in the cars, while in the bottom photo, they are much more clear. The deghosting amount you choose depends on the amount of movement in the photo.
Once you have decided on your settings, click Merge in the bottom right corner. Lightroom then adds your new HDR image to the end of the camera roll.
The process for merging HDR photos in Photoshop is very similar to Lightroom. To start, open all of your photos in Camera Raw. Select the ones you would like to merge, and right click. Select “Merge to HDR.” A similar dialog box opens up with options to deghost and align the photos. Once you choose your alignment and deghosting settings, click Merge, and select where to save this new image.
And that’s it! Now you have a brand new photo, separate from the ones you took, that you can edit however you like.
What if I have a large quantity of photos to process?
While Photoshop is valuable for producing precise HDR photos and fine-tuning them, it can be time-consuming to process each photo one at a time. One advantage to using Lightroom, as opposed to other software, is that Lightroom can treat groups of photos as “stacks” rather than individual photos. Once you have processed one, the settings can then be copied and pasted onto the rest of the stacks.
To do this, import all of your photos into Lightroom. Select all of the photos, and right-click on one. Select “Stacking,” then “Auto-stack by Capture Time.” The dialog box that pops up asks you how much time you would like between your stacks. Move the slider until you see the number of stacks you are expecting, or how many photos you took. If you shot in AEB mode, this should be pretty accurate because the bracketed photos were taken very quickly one after another.
Once you have your stacks, right click and select “Stacking” then “Collapse All Stacks” to make it easier to see the groups. A small white square with the number of photos will appear in the upper left corner of each stack.
Now make your first HDR like usual. Then select the second stack and press CTRL + Shift + H. This will paste the settings of the last HDR you merged onto thenext stack. Repeat this on all of your stacks, and Lightroom will process them all at once, rather than one at a time, and add them to the end of your camera strip, where you can edit them as normal.
I’ve found that this is the most efficient way to process a large quantity of HDR photos, with the most accurate results. Now go out and shoot your own HDR photos and share the results with us!
If you’d like to learn more, please check out some of our other drone photography tutorials, or simply follow dronegenuity on our social media channels, YouTube, and subscribe to our mailing list for regular updates.