What does the "Flux" effect of Instagram do?

Question

Whenever I'm done doing Post on my photos and share on social media, Flux from Insta always seems to magically make my photos "pop". No matter if they're portraits, landscapes - it seems like a very clever algorithm is used to amplify contrast while maintaining a healthy exposure.

What I'm wondering is - what exactly does it do? I want to reproduce this effect in LR but I'm not sure if it's as simple as a step-by-step (something maybe a preset could be made for) or if IG actually analyzes the photo and then generates an S-curve that the slider works with - something that would be a little tougher to replicate.

Here's a before/after to show you what I mean:

Before:

After:

I'm also totally open to any general pointers or resources for better post, as I know my attempt above is rather "flat".

Answer 1

The After photo has 4 main changes that I can see:

1. More contrast
2. Increased exposure
3. It has been Softened
4. Increased saturation/vibrance of the color (though the blue channel is now over saturated i think).

As a result there is much more detail in the dark areas like the man's shirt, the trees etc, the colours 'pop' more, the softening makes everything slightly nicer to look at as you lose just enough detail for things to look smooth, particularly skin etc.

Answer 2

It appears this is a simplistic filter that people that don't know how to properly post-process a picture, which is all Instagram users to first approximation, can throw crap at them and still get somewhat good results.

Except for unusual situations, the first thing you should do in your post-processing workflow is to make the blacks black and the whites white. At the very least, stretch the range to cover 0-1. Since your original picture was poorly processed, or not at all, this actually helps.

Here is the original:

Here it is with the ends of the range stretched to the full 0-1 range:

The black level in the original was (.031, .041, .038) and the white level (.896, .900, .904). Stretching those to (0,0,0) and (1,1,1) respectively fixed the blacks looking muddy and made the bright parts look brighter.

Most pictures will have areas where detail in dark areas appear to be lost once the black level is moved to full black. Instagram may be betting that this is the case, or maybe the algorithm even looks over the picture to see if there are large area that are quite dark, or that the picture is dark overall.

Here I applied what my program calls a "brighten" of .4:

This leaves the ends of the range alone, but brings up the dark values quickly while modifying the bright values less. This gives you better shadow detail and a overall brighter look.

There are various ways to do non-linear brightening. I can go into the math of this particular one if you want, but I am really just trying to show the concept. This is not exactly what the filter you show did. I could probably fiddle with the controls of several non-linear brightening filters to replicate that, but at this point I think the general method is clear enough.

Answer 3

I noticed that on most cases it can give a pop to your photo in a good way in my opinion specially on small screen size. It looks like it's a mix of increasing local contrast and vibrance and probably up the exposure little bit (not sure of this one though).