How to realistically brighten shadows in GIMP - Mantiuk and Retinex in G'MIC

@sguyader Works for me on @partha’s standard build for win7.

image

image

My Gimp comes from the “gimp-git” package in Arch Linux AUR repo. Maybe there’s something to set in configuration before compilation.

My new Nikon by default takes photos like the resulting image here. I call these types of photos or images great for evidence purposes! As far as my taste, I prefer to see or preserve some (realistic) shadows.

As such, I set my Nikon D5600’s defaults to “Exposure Compensation -0.3” and “Flash Compensation -1.7”.

However, every now and then we do have to work with a poorly exposed photo, and will certainly try to remember this write-up for my next encounter! I have yet to be able to get adequate desirable realistic lightening of any poorly exposed photo/image, hopefully this will help. It’s more of a question as to whether resolution has been permanently lost in the darker shadows/areas of the image.

My 2.9.6 came from Arch (I’m using manjaro) and those options are there.

I’m using Manjaro too. But Gimp 2.9.6 is from the “gimp-devel” package, it’s a different one.

Hi Sebastien, Screenprints attached

Screenshot_20171119_122938,

hope these help

Now I feel really dumb… I just didn’t look in the right place. I looked in “Filters” and “GEGL operations”…
It is there in Color > Tone mapping. Thanks @afre and @bminney.

2 Likes

Good strobemansship will always* lead to more natural light than good postprocmansship. Even if there are multiple light sources and can’t see any of them in the photo, the light is still bound by the laws of nature. When brightening shadows in postprocessing you’re only increasing pixel values with complete disregard for reflection, refraction, scattering, etc.
e.g. Speedlite Interior | Larry Lefever Photography

* My “never” and “always” have a 3 year expiry date.

2 Likes

Here’s my take on it

It’s not quite perfect as the bottom right chair has certain problems. Done with Krita with only filter layers. I could import this file as a file layer in Krita and apply LAB adjustment for finalization. The red are overblown.

Did a little bit more fix-up in Krita.

And finally, with a duplicate of a layer, and converting layer color space from RGB to LAB with color adjustment applied, and make the layer to saturation blending mode, and you get this.

I been looking at these pictures more, and this raise a question. Who has the correct color calibration here? I noticed some looks better and worse in different devices.

Very late to the party but had to play with that image too.

shadows

Mostly curves used a very simple guided filter to protect some of the highlights and add a bit more local contrast. :slight_smile:

3 Likes