Please shed a little light on these layers of dark magic

NeilL

Below I have copied, from another forum, instructions for a sequence of processing steps with layers and masks. The description is so condensed as to be cryptic, and I get no more clear a notion of what is being described than a blind man can get of an elephant with his fingers!

Thanks very much to anyone who can help clarify.

If I put it here as I found and extracted it (btw its context was a thread discussing the tailoring of noise/grain for use in taming the artifacts created in interpolation in enlargement) could someone have a go at unpacking it and making it comprehensible, in particular what is meant by "grain masks" and where they come from? I understand that 2 new layers have been created and each one contains a different curves adjustment (of the target image I suppose???). I understand that another layer contains the grain/noise. But how this grain layer becomes a mask, normal and inverted, for the curves layers is where I go off the tracks! (Or perhaps the two curves layers are adjustments to the noise layer????) I have recently come across similar descriptions for applying effects through layer masks, and all of them similarly opaque. I just know there is some very valuable magic here.

Here it is:

Clearly these two curves annihilate each other (which is mandatory) without layer masks.
One needs some appropriate layer masks. Appropriate means here that the mean luminosity value of the layer mask must be around 127. You can take scanned grain, artificially created etc.

Now just put the grain mask to one and the inverted grain mask to the other curve.

So now you have total control over the responding behavior of your artificially created film; you can add further control points, put the two curves in a layer set and control the strength etc.
All non destructive.



Neil

basflt

mayby this helps

http://photoshoptutorials.ws/photoshop-tutorials/photo-effects/natural-film-grain.html

NeilL

basflt wrote: »

mayby this helps

http://photoshoptutorials.ws/photoshop-tutorials/photo-effects/natural-film-grain.html

Thanks Bas. Good link, however pretty straightforward. Where I'm getting baffled by the instructions I quoted is in the use of layer masks. Layer masks are used for editing the info in layers, I didn't think they brought new data to a layer, which seems to be what is being described.

Neil

basflt

if one uses very difficult words to explain something simple , then , he is not explaining


the layers act the same as masks ; whites are used , blacks not
with two opposite layers [ one was inverted ] you can adjust in both directions

the only part that confuses me , is All non destructive
changes made never destruct the original , until you merge and save

btw
cannot try myself ATM , as im rebuilding my pc

Richard

Neil,
If the original thread is in a public forum, perhaps you could post a link to it so we could get a better idea of the context. I understand masking fairly well, but what you quoted seems incomprehensible to me.

NeilL

basflt wrote: »

if one uses very difficult words to explain something simple , then , he is not explaining


the layers act the same as masks ; whites are used , blacks not
with two opposite layers [ one was inverted ] you can adjust in both directions

the only part that confuses me , is All non destructive
changes made never destruct the original , until you merge and save

btw
cannot try myself ATM , as im rebuilding my pc

Thanks bas, I understand what you are saying.

How to create and drive 2 curves layers, a grain layer, normal and inverted layer masks, in order to fine tune the effect of the grain in the image is just bogglingly inaccessible in the guy's post.D

Neil

NeilL

Richard wrote: »

Neil,
If the original thread is in a public forum, perhaps you could post a link to it so we could get a better idea of the context. I understand masking fairly well, but what you quoted seems incomprehensible to me.

Thanks R. Yeah, it calls for sympathy, that's for sure!

It seems to me what this grossly inarticulate incantation is mangling is a manual way of doing blend-if.rolleyes

Here is the thread in question:

http://www.luminous-landscape.com/forum/index.php?topic=24521

Neil

Richard

OK, I looked at the thread but I'm afraid I still don't grasp all the mechanics. There used to be an attachment, but it's gone. Maybe it was a screen shot of the layers palette, which would have been quite useful.

It looks like he's trying to control the highlight and shadow components of the noise independently, but his method seems a little convoluted. I think you can accomplish much the same thing by applying a copy of the noise layer as a mask in the noise layer, then (if you have CS4 or above) fine tune the effect with a combination of the layer opacity and the mask density.

NeilL

Richard wrote: »

OK, I looked at the thread but I'm afraid I still don't grasp all the mechanics. There used to be an attachment, but it's gone. Maybe it was a screen shot of the layers palette, which would have been quite useful.

It looks like he's trying to control the highlight and shadow components of the noise independently, but his method seems a little convoluted. I think you can accomplish much the same thing by applying a copy of the noise layer as a mask in the noise layer, then (if you have CS4 or above) fine tune the effect with a combination of the layer opacity and the mask density.

Thanks for your interest and help, R. Much appreciated!

Mmmm... you have given me food for thought. I'll have to take that for a spin!

Neil