nospam
In article <5b5n1aps0r91vq2jjdshpfj3e6dt82ckhk@4ax.com>, Eric Stevens <eric.stevens@sum.co.nz>wrote:

Sandman
All image effects in Photoshop are 100% reversible.

nospam
image effects in photoshop *can* be reversible, but they are not always because photoshop is at its core, a pixel editor. you have to take additional steps for something to be non-destructive.

Sandman
True - but the undo function in modern software is the perfect definition of a reversible process. It can reverse any effect done by anything in Photoshop.

nospam
undo only exists while you're using the app and it's within its undo history. at some point, it won't be undoable, generally when the file is saved but sometimes well before that, depending on the app. that's the whole problem with a traditional workflow.

with a non-destructive workflow, anything can be reversed at any time because the original data remains unaltered, including long after the app has been quit and even archived and later worked on with a different computer.

the difference is very important, and one which floyd and eric do not fully understand (or at all).

Eric Stevens
Of course I understand it!

nospam
based on what you've written in this thread and in others, no you do not.

Eric Stevens
You should stop and think a little about what you are actually doing. You are NOT editing the image until you export it in some way.

nospam
proof that you do not fully understand it.

Eric Stevens
Then you explain what happens.

nospam
i have many times. go revisit the thread from a month ago about files.

or peruse adobe's documentation and/or books/videos on lightroom.

the information is out there.