@Tony_Kuyper recently posted a link to an article of his about using Linear Profiles in Lightroom.
@Kris_Smith posted an image where she used LR HDR Merge to blend exposure brackets for a high dynamic range scene, and she tried using raw files with a Linear Profile as the starting point.
I normally blend exposure brackets manually using TK luminosity masks, but I was interested in Kris’s idea about what profile to use for HDR Merge. Does it make a difference? So I played with it a bit using a 4 image bracket of a sunset from Cape Cod, and trying HDR Merge. I did this starting from raw files with LR profiles of Adobe Color, Adobe Neutral and Linear. I did this using the “Auto” option checked in Merge HDR.
Here are the same raw files under different profiles (I’m showing only the darkest and lightest brackets for each, there were two other intermediate exposures used for the merge as well).
The same raw files with different profiles
Adobe Color Profile
Adobe Neutral Profile
As Tony discusses in his article, Linear gives a flatter, darker starting point. My intent was to see how profiles affect an HDR Merge (including auto checked). Here are the DNG file outputs of HDR Merge with auto checked. No changes were made to any sliders, other than what Auto did.
Adobe Color HDR Merge with Auto
Adobe Neutral HDR Merge with Auto
Linear HDR Merge with Auto
Most people using HDR Merge would make further tweaks to the DNG files sliders, but for the purposes of this discussion I just wanted to see how the different profiles yielded different results as a starting point for further processing (rather than as a finished product).
My observations (and maybe I’m ignorant about how HDR Merge is supposed to work, but I don’t use it all that often, however Kris’s post got me curious intellectually).
Adobe Color profile adds a lot of contrast that risks blowing out the area near the sun, and adds contrast in the shadows that would need to be recovered with further processing. Using Adobe Neutral profile protects the highlights near the sun pretty well, while adding less contrast to the landscape. Linear produces the flattest file of all, but to my eye it does not have a huge advantage on highlight protection over Neutral (in the area near the sun). If you want the most control over further adjustments to the DNG file, then Linear gives you more latitude to bring in contrast where you want it. And after seeing this, I would never use Adobe Color for HDR Merge again, it doesn’t handle extremes as well as Neutral. If you didn’t want to spend the time to take more manual control over adjustments using Linear, Neutral might be a decent compromise. It depends how much work and control you want to put into it. YMMV
I think the biggest takeaway for me is that the profile of the raw files does matter in terms of how the HDR Merge starting point DNG file looks. It’s something that I probably failed to think about enough in the past. I do most of my blends manually with LM’s rather than with HDR merge, but I’m sure that what profile one uses as a starting point matters there too.
@Kris_Smith I did try an HDR Merge with Linear for the sky brackets, and Neutral for the land brackets. Here is that result. It didn’t handle the sky near the sun quite as well as Neutral.