Photoshop intuitively adjusts the reverse negative processing effect

In fact, there are many tutorials on adjusting photos to reverse film negative processing effects (you can see it in the "Related Articles" below), why do you need to write this tutorial? In fact, I think what they wrote is also very good, but some processes can be better. I think this process allows you to choose your own parameters instead of always accepting the parameters they say, such as "check 'Invert', blend mode Use 'Multiply', Opacity 50%, OK".

In fact, we don’t know why we chose 50%, but the parameters they chose have good results, but not every photo is the same, so we have to find a method that is specific to the image itself. I feel that the examples I saw are not intuitive, so I hope to tell you an intuitive method. The parameters of each photo are different, so we need to feel the process.

To sum up, the main process is :

1. Blue channel: Apply the image, select Invert, use Multiply as the blending mode, and adjust the opacity yourself. 2. Green channel: Apply the image, select Invert, use Multiply as the blending mode, and adjust the opacity yourself. 3. Red Channel: Apply image, no need to invert, use color deepening in blending mode, adjust opacity yourself

Blue and red should be inverted and multiplied, while red should be darker.

The process is the same for every image, but opacity is the most critical element that affects the effect.
I am not very satisfied with the process in the tutorial, so I hope to give you a better explanation of the process. Let’s take Lin Chiling’s version of the picture as an example. I will ignore the color levels and curve adjustment. Here are the screenshots:

1st original picture:

The main screen for selecting a channel in the second picture will be grayed out:

In the third picture, click on the eye of the RGB layer, and the picture will be normal, but in the channel editing state:

For the fourth picture, select the blue channel, Image->Apply Image, Invert, Multiply:

The fifth picture deals with the transparency value and feels the changes in the picture:

For the 6th picture, select the green channel, Image->Apply Image, Invert, Multiply:

The seventh picture deals with the transparency value and feels the changes in the picture:

For the 8th picture, select the red channel, Image->Apply Image, Color Burn:

The 9th picture deals with the transparency value and feels the changes in the picture:

The 10th picture is completed:

The best thing about this process is that it allows you to feel the changes in the image and adjust it for each image. I hope it helps!

Additional thoughts :

The "reversal negative charge" simulation in my concept is the following process:

• First, we need to simulate the visual feeling of a reversal film: the color saturation and density of the reversal film are greater than that of a normal photo, so we can: copy the original image layer and overlay it at 50%.
• Next, treat it as a reversal film as a "negative film", that is: Ctrl + I, invert.
• Put it into the LAB shared space to convert it once, that is, map it as a negative.
• Ctrl + I again to invert. Convert back to RGB
• Then adjust the curve tone appropriately, and this is what it looks like.

Maybe the color is different from the "reverse negative charge" done above, but this is the most explainable "reversal negative charge" simulation process.

Original picture:

After completion:

Additional thoughts :

Adjusting in RGB mode will make the colors of the image lighter and flatter. After all, RGB mode is additive blending.
So I tried adjusting it in CMYK mode, and as expected, the colors became very vivid, close to the effect of a real reverse film negative process.

The following are pictures adjusted in CMYK and RGB modes:

CMYK

RGB