While processing some images I took earlier this week, and going through some of the bracket sets I captured for HDR purposes, a question popped into my head that made me stop and think, and then write…

How Much Of  A Difference Is There Between A Three Frame and Five Frame HDR?

Well, naturally, that depends largely on what software you use to process your HDR images. For this exercise, I used Lightroom, HDR Efex Pro, and DFine2.0. I was curious to see the difference between a 3 shot, and 5 shot HDR image, and which one ‘looked’ better. So lets dig a little deeper into the workflow from capture to final image.

Capturing The Raw Data

Bay View Park on Coronado Island is where I captured the San Diego Skyline just after sunset, when the blues in the sky were at their peak. I set the camera to bracket at full stop increments, the three brackets were set to -2, -1, and 0. The five bracket set was -2, -1, 0, +1, and +2. At the time, I don’t know why I decided to do a 5 frame bracket, but I’m glad I did.

Cooling Off Period and Post Processing

Letting a full day’s worth of shooting cool down for about 48 hours is a recent addition to my workflow. This cooling off period lets my mind rest, and kind of marinate a bit on how I’ll process the images later. I’ve also found that when I go back to review the images, I’m much more efficient throughout the entire post processing session. I also try to remember to take breaks more often than I’ve done in the past. There aren’t any deadlines to worry about and taking a leisurely pace (for me) produces better results. The same is true while capturing images in camera also, slow down, compose, and shoot will often yield better images.

Once I got my images imported into Lightroom, I then exported the three image set into HDR Efex Pro, where I processed them to get the look and feel I wanted, then saved the settings so that I could apply the exact settings to the 5 image set. Once both sets were processed, I dragged them into Dfine 2.0 for noise reduction.

Histogram Comparison

Comparing The Results

I did a side by side comparison, at first glance, they were pretty subtle. A closer look at the histograms gave a better indication of what was going on. The first thing I found was the blue channel in the three frame bracket shows a definitive spike compared to the five frame image. Overall, the profiles have fairly different characteristics. Histograms are one thing, but what do the final images look like side by side? I’m so glad you asked.

Below is a side by side screenshot of the two images, the three frame HDR is on the left, and the five frame HDR on the right. The darks are softer, and gentler in the five shot version, and the range of color gradation from the horizon to the sky is more appealing (to me anyhow).

Final thoughts

This fun little experiment is not by any means a definitive answer to the question of how many frames should one use to create an HDR image. To answer that question, I’ll simply say take as many as you need to that make sense, and fit your own workflow. Whether you are using a single image, or a baker’s dozen, or more, it all comes down to the final image. Speaking of which, here is my final image for this post…enjoy.

San Diego Blue Hour – HDR

What is your HDR workflow like? How many frames is too many? Feel free to comment and share your techniques.