Image editing for beginners

Thanks romke for putting in the time and effort to make this excellent tutorial. A very clearly written and illustrated contribution

Thank you very much, Romke, for all the effort!

It is well written and pleasure to read, as your articles (and comments) usually are. It is interesting even for someone who is not totally novice, and I also learned few things and tips while reading it (and while discussing with you).

Congratulations and thanks. A lot of work.

Just one remark.

There are at least two views on non-destructive editing.

1. The oldest one, before the introduction of Lightroom, was the remark that you could loose tonal information in each color channel bij editing your picture.

Each color channel, R - G and B, has only 255 color values in 8-bit mode. By adjusting levels it is possible to clip values at both ends of the histogram loosing information. By adjusting the contrast and stretching a histogram the resulting picture will have hard tonal transitions leading to solarization effects in a print.

Reducing each color channel to 200 values from 255 will already result in a reduction to 8 million tones from 16,7 million possible tones.

In the oldier versions of Photoshop up to version 7 most if not all adjustment tools are destructive. For that reason the pioneers of digital pp developed their own techniques of non-destructive editing, working in 16 bit-mode and based on the use of layers.

Adobe introduced in later versions non-destructive commands, adjustment layers and finally smart objects and smart filters to allow non-destructive editing in the meaning of not loosing information.

2. The second opinion of non-destructive editing was introduced by Adobe with the first introduction of Lightroom. Maybe as a result of the criticisms on the destructive editing tools they argued that Lightroom was a non destructive editing program because the original raw file remained unchanged.

In this article described as parametric editing, keeping the adjustments as a separate set of intstructions only applied with printing the raw file or by converting it to a jpeg-file.

This view however is irrelevant for these reasons:

- Working in jpeg you can avoid destructiveness in this meaning, changing alteration of the original, simply by using a duplicate file. For that reason Photoshop has a duplicate command and it is recommended to use it.

- The final goal of pp is to create an optimised result, either for viewing on screen or for printing.
The second view on non-destructiveness, in the meaning of not changing the original file, does not avoid that the converted jpeg or the final print are destructive.
Despite the fact that the original raw file is not changed you can destruct your final result by loosing information in the RGB channels during the conversion or printing.

For that reason it is recommended to edit in 16-bit mode and in the wider Prophoto RGB colormode.

It would be better to restore the original meaning of non-destructive editing in the meaning of not losing tonal transitions. The second meaning leads to confusion and ensures that people are not aware that editing can lead to information loss in the end result.


I apologize for any unusual or wrong expressions. English is not my native language.

PS A long time since my last post here. Over a year I have fought against ME. A very scary and life-threatening disease. But I'm getting better now. Greetings.

Some clarification.

The current ongoing meaning on non destructive editing is:

1. Destructive edits change the original image data.

2. Non destructive edits do not change the original data.

But you can change (edit) the original data also in a non destructive, reversible way. If I have enough room in the histogram and I shift my tonal values of the red channel to one side of the histogram without clipping values then the original data is changed. But without any loss of information and totally reversible.

Changing data is not the problem, but loss of data. The original meaning of non-destructive editing was to prevent loss of information. Changing a tonal value is not a problem as long as it is reversible. But loosing a tonal value is a problem.

If my parametric set of instructions leads to loss of information and solarization in my final print then my result is the result of destructive editing. It is reversible in the sense that I can use the original and redo my pp work, but with other non destructive instructions to avoid the solarization in my final print.

Greetings

Brilliant!! 5 starz!

Awesome post! Still reading through it, but I'm excited to practice some of these techniques.