Oct 16, 2017
What is HDR photography? How do you do it? Why do/should you do it? When do you use it? I'll answer these questions and more in this week's blog post on this special process photographers use to bring out more detail in high contrast situations, like when I made the image above.
The way our eyes see light to dark is different from the way our cameras see, mainly because of the way our retinas work. The rods and cones in our retina work together to help us see a wide range of detail, and adjust to the light levels around us. Typically, in brightly lit situations, the cones are used exclusively and read the equivalent of about 10 stops of light. In dimmer conditions the rods activate as well, and as things get even darker the rods take over completely. Once our eyes adjust to the dimmer light, their dynamic range increases to around 20 stops of light for most people. This allows us to see a wide range from dark to light that our cameras have a harder time keeping up with. The best digital cameras out there currently have a dynamic range up to about 12 stops of light, and even then you must shoot in RAW format at the lowest ISO's to record that amount of information. In high contrast situations, it's really hard to capture a full range of detail from dark to light in one image. Typically these moments can also be some of the most dramatic, so how can you capture them effectively?
When you are in the field, there are a few ways you can attack this. Using a graduated neutral density filter on your lens can sometimes help, by darkening in highlights by two or three stops, or sometimes more. This only works if you can get the dark area on the filter to line up right however, so it's not a catch all solution. If you're shooting with the intent to process using HDR later, you can do this two ways. You can bracket in the field by shooting multiple exposures to blend after the fact, and if there is nothing really moving in your frame between shots this will be an effective solution. If there is something moving to much between shots, you can try to capture as much as possible in one image, typically favoring saving the highlights, and then using exposure compensation in your editing software to create multiple versions of the same photo at different lighting levels. I've used both methods depending on the situation. The goal is to have a range of exposures to work with, ranging from one dark enough to capture all or as much as possible of the highlight detail, up to one that has as much shadow detail as you want to bring out, and maybe a little more just for good measure. You'll also want to make sure you're shooting in RAW format to capture as much detail as possible. From here the finishing work is done on the computer.
Full versions of Adobe Photoshop have a built in HDR tool that works decently well, but there are also quite a few third party PS plugins that work even better. The one I've been using is from the Nik Collection, called HDR Efex Pro. While Google has chosen to no longer update the Nik Colllection of plugins going forward, it is still fully compatible with all versions of Photoshop and still works well. You pull all the versions of you image into the software, make some adjustments for whether you want it to come out lighter or darker, and then are given some options for how you want the final image to come out. Often once I bring the image out of the plugin and back into Photoshop, I'll tweak it slightly to bring contrast back into line, as HDR processing tends to create images that are kind of flat. Once completed, you should have an image with much more detail than you could have captured in a single frame in the moment, and is probably closer to how your eyes interpreted it at the time. This allows you to bring those dramatically lit moments to life in your photos in an equally dramatic way. Enjoy one more HDR image I made this year below.
For a limited time I'm still offering all of my autumn images at 25% off, including new photos I have added from this fall like the one above, so visit my special autumn seasonal gallery and choose some special fall season artwork before this special discount runs out. If you're enjoying following my posts here on my blog, don't forget to follow me on Facebook & Instagram as well. You'll often see my newest photos there first. Thanks for following along!