I am pretty sure this is a dumb question but bear with Photoshop beginner.
 

If I want to paint a particular area of an image I can make a selection and the strokes will not flush outside of the selection. Good. But isn't there an easy way to change the transparency of the selection? Without having to create a mask I mean? After all is much easier to draw a slider than vary the greyscale of a mask.

What I do is right click on the selection and select Layer Via Cut. That cuts selection out of layer making a new layer. You can then use the slider to adjust transparency of the new layer.

Yes, that seems the best way. That can be a workaround for "Paste in place" too. I am sure there is a shortcut for "Paste in place" but I have forgot it. :(

Another way of doing this is to make your selection of the area you want to paint, then create a new layer (shift+ctrl+n).  Your new layer should be now active with your selection still in place.  Now when you paint , your strokes are going onto the new layer not your original layer.  Now you can adjust the transparency slider of the new layer without affecting the original image underneath.  You can now perform any function on the new layer to get the effect you want (blur, erase, levels etc).

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If I’m not misunderstanding the question, after selecting an area of an image you can press Ctrl + X. This will completely extract the selected area from the image to clipboard memory. If you then press Ctrl + V, this will paste the selected area on its own new layer where it can be manipulated at will without disturbing the surrounding image area. If instead of pressing Ctrl + X you press Ctrl + C then the selected area will merely be copied to clipboard memory unaffecting the original. Then pressing Ctrl + V will paste a copy of the selected area on its own new layer. On the other hand, if you have selected an area of an image and you just press Ctrl + J, this will automatically copy the selected area unto its own new layer as well saving you the extra step.
 

Okay if I sum up what you all say I need THREE new layers to manipulate an area of the original image.

1. One new layer UNDER the original for the bump map or material or what you call it.

2. One new layer OVER the orginal with the cut-out (made with control J  = the same as Layer Via Cut)

3. One additional layer OVER the original to paint on (in case you make a mistake)

Then I can adjust the transparency of both layer 2) and 3), making the bump map/ material l/texture shine through exactly as much as I want to.

It is never easy is it?

(Layer 3 should be a clipping mask of course, made by right clicking and selecting  "Create Clipping Mask)

Looking at your image of your layers it looks to me like you are wanting to create your own texture map for a 3d model.  If that is the case then here is how I do it.

Firstly before you do anything else duplicate your original layer then turn its visibility off.  This preserves your original image so you can return to it if you mess things up.

I then make a 'flats' layer which is a flat coloured layer that allows you to make instant selections with the magic wand of any of the parts of the texture map.  I do this by using the magic wand and clicking on the white part of the copy original texture map and then inversing the selection.  I then create a new layer (shift+ctrl+n).  With the selection still active I paint a flat coloured layer on the whole selection.  This now becomes my selection 'template' for all texturing work.  I then move this layer below the copy original.

Next using the magic wand on the texture template I select the part of the map that I am going to work on.  I then make a new layer from this selection (shift+cntrl+n).  I then paint on this layer.  Any corrections that need to be made to levels, clour balance, contrast/brightness etc are then done with an adjustment layer>clipping mask.

Keep repeating the above instructions for any other changes to the copy original texture map using the selection template for quick selections.

A bump map needs to be saved out as a separate image file if it is to be used in something like Poser.  Your bump map only needs to be in grayscale to get the high/low information.  I usually create the bump map exactly the same way as described above using the selection template, then turn off the visibility of all other layers when it comes time to save it out to a new file.

In dreamer101 and Quests post above the Layer via Cut and the shortcut cntrl+j are the same thing.  The reason that I don't generally use this method is that if you make a selection on your original image and cut this selection to a new layer and only partially paint on this new selection layer then if you make any level, curve, colour balance etc changes to your original image then the un-painted part on your new layer will not reflect those changes.  Correcting this by erasing can be difficult if you used a soft brush in your texture painting.

These tips work for me, others will have their own way of doing things.  Try the suggestions of the other responders here and find the one that best suits your needs for your current project.

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I gathered that what Tess_Linn was asking was if it was possible to work solely on her selected area without the need for a mask to implement transparency options. Not knowing what the intended use was I simply offered up possible options and methodologies for area selecting which could work just as well and even if you are working on different layers you can always provide an adjustment layer at the top of the stack where all the lower layers can still benefit from the use of curves, levels, hues & saturation, etc. Or you can just isolate one layer. Please note that I was not offering a work flow process and my examples here should not be interpreted as such. As I’m sure has already become evident is the fact that there are many ways to achieve the same results in Photoshop. As you become more experienced and proficient using the software you will no doubt develop your own way of doing things. In that respect the program is just beautifully that flexible. As a side bar Tess_Linn, you can also create a clipping mask by holding down the Alt key while placing the mouse cursor between the layers and clicking when you see the cursor turn into a double bubble.

My fault, pardon me for using the wrong terminology. Texture and bump maps are 3D speak. In Piranesi they use the terms “texture” and “grains”. Texture can be color, grains is always greyscale. When I mention texture in Photoshop I mean an image that is under the original image shining through because of the (partial) transparency of the layer above. “Grain” I understand as a greyscale image added to a brush. I never need to export a “bump map to Poser or any other 3D program because the workflow is always going the other way, from 3D to Photoshop. In short, I want to render the 3D image in Photoshop.

 

So with the information I have now the workflow for a fictive house house will be thus,

 

1)      In My 3D program I colour all the different parts of the house, wall, front side, and so on with different  (temporary) colours. The colours are only for so it will be easier to pick out the selections with the magic wand in Photoshop.

 

2)      Then in Photoshop, I cut-out all the different parts to separate layers, using dreamer101 and Quests method Layer via Cut, collect all in a group. (+ and backup I actually made a mistake in 1983...), Now the original image is no more, all shopped up.

 

3)      Then I can go through all the parts in turn, put a texture map under and a clipping mask over (thank you I didn’t know about that.:) over each object.

 

The advantage of this is that I am the whole time seeing the whole finished image + any texture or “grains” added to it. And I can easily correct mistakes or try a different approach.
 

tess_linn,

I  now see that this post relates to your other "Challenge" post.  The image you posted above of your layers in photoshop was not large enough to see detail and it looked to me like your layer titled 'Original' was a texture template that would have been created from UV mapping your 3d model.  Having a layer titled BumpMap also indicated this.  Thats why I gave a workflow suggestion as I thought it may be helpful.   I can now see that it is actually parts of your 3d house that you have selected out of your rendering.   My suggestion to create a flats layer was to assist in painting a texture template to apply to the 3d house within your 3d program before rendering.  If you are working on the final rendered image of your house then photoshop has good selection tools to extract exactly what parts you want to separate onto different layers.

If you did want to try the method you mention in point 1. of your post above I would suggest that you render out of your 3d program two images.  One with the textures such as roof tiles, brickwork etc applied and the second one with the flat colours for easy selection in photoshop.  Just make sure that for the flat colour rendering you turn shadows off otherwise this would create shading in your house parts making selections with the magic wand harder.   So long as you don't move your camera between renderings you can then combine both renderings into the one .psd file.  To combine the renderings open both in photoshop.  Press ctrl+a to select the whole of one image then V to select the move tool.  Then hold down the ctrl key as you drag the selected image onto the other one.  This will place the dragged image exactly in the center of the second one so that selections you make on the flat colour layer match the textured layer.

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keppel,

 

It was my fault entirely as I was confusing things, unable to

"think or express my thoughts in a clear or orderly manner"

 

But anyway, getting that right I find that we are thinking in the exact same tracks, namely =

"Now that I know what to do with the flat version why waste the rendered version?"

?

 

As you say I need to render two versions from my 3D program, one with textures, bump maps, gloss and the whole enchilada, and one with flat colours for easy selection. The two versions need to have the same camera angle and be aligned perfect to the pixel. That will give a lot of possibilities in photoshop.

 

Didn't mama told us never to waste anything? :)

tess_linn,

To line up your two images as I described in my last post hold down the shift key as you drag one image onto the other, not the ctrl key as I  wrote.  I didn't have Photoshop open when I replied and got the two keys mixed up.  Also if you aren't familiar with the Extract tool yet (Filter>Extract) read up on it as it is a good selection tool that will help with cutting your images up, especially the flats image.

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Shift key ok no problem I knew about that. I don't know what happen to the extract Item it has disappeared from the filter menu in my CS4 extended. Perhaps in disqust by being maltreated by a beginner? :) Or is it a result of installing Mask Pro? Should I reinstall?

?

I'm still using CS2.  Don't know if the tool has been moved or removed in CS4.

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