Layers Question - CS6 or any version

[photos4fun]

I'm likely missing something very simple about layers in PS.

Basic question: how do I create a second (or third or fourth) layer and not have it cover up the work I just did in the first layer?

Context: Let's say I copy the background so I have created my "first layer." I change the mode to screen, create a layer mask and fill with black. All I have to do now is paint with a white brush in the areas where I want my photo lighter - nondestructive dodge.

Next I want to create a "second layer" in order to darken part of the photo (by they way, these are just examples of anything I could do on different layers). If I copy the "first layer" I am just doubling the effecty of the screen changes. If I make a second copy of my background layer, I must move it to the top of my layers pallete in order to see my work, but then the work I did on the first layer is hidden.

I have Matt Kloskoski's book on Layers, but I can't find the answer. I know I can press flatten or merge down and continue, but I want to be able to go back and adjust the layers later by saving in PSD format.

Thanks so much!!

[SpeedGraphicMan]

Uhh... I am a little confused by your post. But let me see if I can make a stab in the dark and answer what I think you meant.

Ok..

You have opened your image...

It says background layer.

You make a duplicate layer and you set the blending mode to screen...

You should create a blank layer with the mask <in between> the background and first layer, Is that what you want?

If so, just hit Ctrl + Shift + N to create a new blank layer above the highlighted one.

I hope I understood what you are trying to do.

Cheers...

[photos4fun]

I'm likely not explaining it correctly because I don't know enough to really understand... When I create the second layer and put a mask on the top layer, it is blocking the work I did on the first layer (with mask).

[Steven G Webb]

Hold down the "Alt" key when you create the mask layer?

[mistermonday]

There are a number of ways to keep your layer stack non destructive and workable.
The 1st thing I would suggest is to make use of Adjustment layers where you can. In the example you presented above, instead of duplicating the background and setting it's blend mode to Screen, add a Levels or Curve Adjustment Layer, do not adjust the Levels or Curves but just change the blend mode to Screen. This will give you the exact same effect and these adj layers automatically come with masks. You can simply type Ctrl+I to invert the mask and make it black.
At some point as you are building up your stack you may need to work on a composite of what you have already done. To do this, click on the top layer to make it active and then type CTRL+ALT+SHIFT+E which merges every visible layer below and puts that merged layer into a new layer on top of the stack. This merged layer is also maskable. You can also group layers into layer groups and set the blend mode of the group to pass-through. Then there are Smart Objects which you can use to create fully editable layer stack.
I suggest you work on some real projects and when you get stuck post a specific roadblock that you hit and people will be happy to post suggested solutions. In PS, there are almost always more than 1 way to do the same thing.
Cheers, Murray

[keithdewey3]

This makes me realize how much I don't know and still have to learn about photoshop. I bet I am not using 1% of the software's capabilities and I think I know a lot.

[mistermonday]

Originally Posted by keithdewey3

This makes me realize how much I don't know and still have to learn about photoshop. I bet I am not using 1% of the software's capabilities and I think I know a lot.

It's an ongoing learning experience. I've been using the program now for just shy of 20 years and learn something new every time I use it.
Cheers, Murray

[Sailor Blue]

Originally Posted by photos4fun

I'm likely not explaining it correctly because I don't know enough to really understand... When I create the second layer and put a mask on the top layer, it is blocking the work I did on the first layer (with mask).

No.

[photos4fun]

Originally Posted by mistermonday

There are a number of ways to keep your layer stack non destructive and workable.
The 1st thing I would suggest is to make use of Adjustment layers where you can. In the example you presented above, instead of duplicating the background and setting it's blend mode to Screen, add a Levels or Curve Adjustment Layer, do not adjust the Levels or Curves but just change the blend mode to Screen. This will give you the exact same effect and these adj layers automatically come with masks. You can simply type Ctrl+I to invert the mask and make it black.
At some point as you are building up your stack you may need to work on a composite of what you have already done. To do this, click on the top layer to make it active and then type CTRL+ALT+SHIFT+E which merges every visible layer below and puts that merged layer into a new layer on top of the stack. This merged layer is also maskable. You can also group layers into layer groups and set the blend mode of the group to pass-through. Then there are Smart Objects which you can use to create fully editable layer stack.
I suggest you work on some real projects and when you get stuck post a specific roadblock that you hit and people will be happy to post suggested solutions. In PS, there are almost always more than 1 way to do the same thing.
Cheers, Murray

Thank you mistermonday, that is good advice about changing the blend modes of adjustment layers. I have been "merging visible" with CTRL+SHIFT+ALT+E, but when I do that, I lose the ability to go back to one of the previous layer masks to make additional adjustments. THAT is what I am trying to prevent. I just haven't been precise enough in my description to say it that way.

Thanks again everyone for taking the time to respond.

[mistermonday]

Originally Posted by photos4fun

Thank you mistermonday, that is good advice about changing the blend modes of adjustment layers. I have been "merging visible" with CTRL+SHIFT+ALT+E, but when I do that, I lose the ability to go back to one of the previous layer masks to make additional adjustments. THAT is what I am trying to prevent. I just haven't been precise enough in my description to say it that way.

Thanks again everyone for taking the time to respond.

As you work your way up the layers, try to think of how you can maintain a non destructive, "pass-through" workflow. Sometimes and adjustment layer, other times a blank layer (for example to do cloning of imperfections). Most of the time you can get away without adding a "blocking" layer. If you have to perform an action that requires merged or rasterized layer (like the Shadow/Highlight command) try to do those at the very beginning or end of your workflow. Remember also that you can always add a "hide all" mask to the blocking / merged layer. A bit of planning in advance plus some ingenuity will get you to a point where the problem is minimized.
Cheers, Murray