It was clear in the previous post that a two-stop overexposure using expose-to-the-right (ETTR) was not recoverable. Is there enough headroom in the Lightroom/D4 pair for a one-stop overexposure? Let’s find out. Here it the correctly-exposed image and its histogram: Here is a one-stop over image and its histogram: Here’s what I could do in… [Read More]

Since this is a discussion that started out to be about raw image processing, it’s reasonable to ask what happens to the 14 bit images typically used in this workflow. At this point, I will switch from synthetic images to real photographic ones, with a Nikon D4 as the test bed. I set the camera… [Read More]

Now, let’s look at Lightroom, and make sure it works the same way as Photoshop. Because Lightroom does some default processing on images, we see histogram depopulation when we first bring an eight-bit image into the program: But we can’t see histogram depopulation if we bring a 16-bit image in: Here’s what we get if… [Read More]

In the previous post, I described histogram depopulation in images encoded with eight bits per color plane, as was the standard until about ten years ago. Nowadays serious photographers use image codings with 16 bits per color plane, which makes an immense difference. Here, in compact form, is what happens when we darken our test… [Read More]

In 1991, I noted the phenomenon that Wells calls combing, came up with a few ways to artfully trade off image resolution for reduction or elimination of the effect, and submitted a patent disclosure to my employer. They weren’t interested in patenting the ideas, but instead published it in order to keep anyone else from… [Read More]