The best technique for realistic highlights?

[norolim]

Hi guys. I've seen some Photoshop masters of photo manipulation, like Benny productions for example, that use blend-if functionality to make the highlights blend better with the object. Here is an example in tutorial: https://youtu.be/2dpWkJeU7TM?t=370, and this is from Benny - https://youtu.be/yUPIChL7_x8?t=427. Is it possible to achieve this in GIMP? Maybe with Color to Alpha? I tried to do it like this:





With color to alpha applied to the first layer (also mask to selection to affect only the area of the highlights)but the results are not very good.

This is the source image in pexels. (I also decreased the temperature and exposure.)

[PixLab]

Indeed it's color to alpha, may be you don't have a complete understanding of Color to Alpha, it works a bit differently than blend if, but it does quite a good job
Here you go > https://www.youtube.com/watch?v=YQCE2_tMcN4

[rich2005]

DM video 16 minutes - too long.

I found this comment about blend-if 
In a nutshell, Blend If does pretty much what Luminosity masks do: It masks out part of a layer based on the luminosity of pixels.

There are several luminosity mask scripts for Gimp available, some just give basic masks, sometimes as a selection, often multiple layers for the user to choose, which can be over-kill.

This plugin allows the user to choose just one (or more) luminosity mask. luminosity-mask-drive-though from github.com/gummycowboy
Just the plugin attached. Unzip put LMDT.py in your plugins folder

It is still up to the user to adjust the result. Using layer modes is one way. 50 second animation example: https://i.imgur.com/QdC51oy.mp4

Note. The posted image is 16 bit. For that example, I recommend reducing to 8 bit

[Krikor]

Tim came up with a version that would try to replicate Blend-if with Gimp. He created the Mask-If plugin.

Always good to try new options.

Read on:

https://gimplearn.net/viewtopic.php?f=18...t=blend+if

https://gimplearn.net/viewtopic.php?f=3&t=2922

[norolim]

Thanks! Those are some interesting plugins to play around with. For the luminosity mask, I used G'MIC's "Slice Luminosity", but now I'm going to try this one.