P: Add Layers to Lightroom

>You claim they are "NOT non destructive", but clearly they are non-destructive.

Clearly? Think about the process and I think you'll see it's quite clear layers are destructive. What do you think happens when you print the document, the layers somehow disappear? That the edits are NOT applied? Of course they are. And there IS data loss. No way around that (and as I said a year ago, moot in high bit but data loss none the less).

The ONLY time adjustment layers are NOT destructive is when you view the image in Photoshop. Flatten, what happens? The edits are applied. You can't edit pixels and change their values and not lose data to rounding errors. The second you do anything like print, flatten, save as a different color space etc, the edits IN the layers ARE applied to the underlying data. There's no other way around this fact you find so unclear!

>>The adjustment layers of PS "create" pixels just like a step in the LR image pipeline "creates" pixels.

No, they don't. You seem to misunderstand not only the processing of the data in these two applications, you seem to not realize that LR cannot alter pixels, it has to render them from sets of instructions. Rendering is the process that takes original data, instructions and creates a new set of pixels from both. With a raw file, that's non destructive. You are (for at least the 3rd time), creating pixels. IF you take a rendered image (TIFF) run it though LR.'s engine, the original is untouched but the rendered iteration is not a non destructive action if you take this edit and compare it to the original data. But we want to alter pixels so you either do so an end up with some data loss or you leave the pixels alone. Adjustment layers alter the pixel value (or you'd see nothing happening).

>This is what parametric editing is about; that you can always revisit your decisions and change them without losing any edits you have done after you made your initial parameter choices.

Yes, ONE part of the process. But look what you wrote and think about it with what I've written: you can always revisit your decisions yes, and since you must render a new iteration, it's original data + instructions equals new iteration from a rendered image and a new creation from raw.

>It exactly corresponds to the "export" step in LR.

No it doesn't. Not even close. Export is a rendering where again, new pixels are created from two possible data sources. In Photoshop, you're directly altering pixel values. Whether you do it without a layer or with a layer, the net results at any time expect just viewing the image in Photoshop is the same.

Alter existing pixels= data loss. Creating pixels is completely different. In high bit, the data loss isn't visible but the data loss is there and one can view the differences between the two easily using the Subtract command with both docs.

Andrew, my sincere apologies for forgetting about the long debate we had. I would not have asked you any questions, had I been aware of the debate.

However, my points stand and you are mistaken on the nature of adjustment layers. You claim they are "NOT non destructive", but clearly they are non-destructive. The reason is that you can revisit the parameter settings of each adjustment layer at any time and any changes to the parameters will be reflected in a new rendering.

Imagine a layer stack of five adjustment layers, each controlling some different aspect (such as hue, levels, posterisation, etc). You can change any of the layer parameters at any time and the overall effect is exactly like the LR experience. You can change sharpness, levels, colour, etc. at any time in any order.

The adjustment layers of PS "create" pixels just like a step in the LR image pipeline "creates" pixels.

This is what parametric editing is about; that you can always revisit your decisions and change them without losing any edits you have done after you made your initial parameter choices.

The non-destructive nature of adjustment layers is their raison d'être. Before adjustment layers, you had to bake in any adjustment (such as a curves adjustment, for instance) into your image and you couldn't go back, change the parameters (e.g., the curve) and enjoy the different result (without losing, for instance, hue adjustments you made subsequently to the curves adjustment).

The fact that the effect of adjustment layers has to be applied once you export a file ("...do anything with the image outside of Photoshop...") is completely immaterial. It exactly corresponds to the "export" step in LR. Are you saying, just because LR can export images and therefore "boom" has to become "destructive? makes it lose its non-destructive status?

P.S.: I should perhaps add that PS adjustment layers are only non-destructive as long you do not combine them with regular destructive layers. The latter will of course be able to override the pixels the adjustment layers "created" (to use your terminology) or create copies of them that won't be updated anymore upon further changes to the adjustment layer. But if you stick to only using adjustment layers, you can replicate a non-destructive LR experience in PS. Again, has this been made possible by a person/team who does not truly understand the difference between the -- according to you so fundamentally different -- "processes"?

I already told you nearly a year ago that layers are NOT non destructive. Well if you decide you want to do anything with the image outside of Photoshop or print it, or convert it to another color space the layers (edits) ARE applied and boom, you've got a destructive edit.

Parametric instructions are just that. They tell a raw processor HOW to CREATE RGB pixels. That is non destructive. You're not editing pixels, you're creating them. But in the year since we last talked, you don't see to have moved past the differences which are rather significant.

Andrew, do you have a technical argument as well?
How do you counteract the technical arguments I've made?

The differences between "the two processes" are current de-facto differences that are historically rooted and are only weakly justified by technical arguments.

Are you rejecting adjustment layers in PS because they are not "pushing pixels", but are an example for parametric editing? Why are adjustment layers in PS not an inadequate mixing of "two processes"? Have adjustment layer been added to PS by someone who does not "understand the difference between the processes and the results each produces"?

>>I frequently wonder why "pundits" push this pixel pushing vs parametric editing idea.

Because we actually understand the differences between the two processes and the results each produces. We actually understand the role of differing applications as tools and use them on the data they were designed to process.

An excellent summary TK. I frequently wonder why "pundits" push this pixel pushing vs parametric editing idea. Andrew must have been having a bad day when he "took umbrage".

Forked to re-merge into a more appropriate thread. Please reference the new topic here: Lightroom: Preserve PSD Layers in LR to allow back and forth editing

I recently replaced our Express Digital Software package that we used to organize, show clients, sell, and print from with Lightroom 3. I has been wonderful. The one thing that it does not have is the ability to do quick collages with a overlay. Do you think Lightroom will be able to import files with transparencies and/or do layers. This would give a studio the ability to create cards and collages quickly. We are in the process of creating a training video directed at the professional portrait studio on how to use Lightroom in the studio.

In addition to the resize option I mentioned earlier, I would like to see an overlay option so that I can combine two photoes.

I just downloaded perfect layers for lightroom.
I find this little plug in amazing, for the ease of use and the power and possibilities it offers
1 thing though is lacking, and i think if lightroom would finally come out of the box and give us such an important tool would be AMAZING!!!

Having the possibilities to work with 2 different pictures like in perfect layers, but at the same time being able to change for each picture any slider of the develop tool.

this function i think would really give to lightroom an edge to any other program out there, and give to user such a huge control and great way to improve quickly images, without the tedious way to have to work the image in an external editor like photoshop

PLEASE
PLEASE