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sully75
15-Mar-2012, 00:53
I have an image that I need to take the sky down on. The foreground is complicated but contrasts strongly with the sky. I can't remember how to make a contrast mask. Not the kind where you invert a layer, but the kind where you make a layer mask that you can overlay on a curves layer.

Can anyone remind me? It's been awhile.

Atul Mohidekar
15-Mar-2012, 01:39
There are multiple ways to create masks in PS. Here is a simple option for your situation:
Select the sky or the foreground (since they strongly contrast with each other) with any selection tool and then click on the new curves layer button in the layer panel. The selected portion will become the mask for the curves layer. If you have already created the curves layer (without the mask), select the layer and then click on the Create Mask button (the empty circle surrounded by dark area) to add a mask to the layer. If you hold down Alt button on Windows or Option on Mac while clicking on the Create Mask button, the new mask will be all black which will completely hide the effect of the layer until you paint on the mask with lighter shades of gray.


// Atul

Jim Noel
15-Mar-2012, 08:36
A faster and easier method:
Lith film + paper developer + hair dryer and I am through while you mess around with PS.

Greg Miller
15-Mar-2012, 08:59
One method that tends to be effective with complex subjects like yours is a Color Range (Select | Color Range). First create your curve layer, the in the Color Range panel, use the eye dropper to select the sky, then move the fuzziness slider to expand or contract the range of colors selected. Click OK and your curve layer mask will now show that selection. You can paint in black or white with a brush on the layer mask to fine tune it.

Brian Ellis
15-Mar-2012, 09:03
a faster and easier method:
Lith film + paper developer + hair dryer and i am through while you mess around with ps.

lol!

John Rodriguez
15-Mar-2012, 09:33
Another method -

If the sky is the only part of the image thats the luminosity of blue you want to edit:

- Create whatever adjustment layer you want to get the sky where you want it
- Option click the layer and select Blend If
- Set Blend If to blend if blue
- Use the blend-if sliders to isolate the shade of blue you want to allow. Option click the slider to break it into two endpoints. How far you place them from one another dictates the smoothness of the blend.

Daniel Moore
15-Mar-2012, 11:34
And yet another,
Switch to the Channels palette, hold down a Control key and click on the thumbnail icon for the RGB channel, this will select anything over 50% luminosity, then create a new adjustment layer, I suggest Curves. That will create the mask as the same time as you'll see. Then adjust the mask by choosing the brush tool, set the appropriate brush size, choose Black for brush color, click on the mask icon itself, and quickly paint on the mask over any foreground areas that may have been selected previously.

Further, while looking at the Channels palette, click on each individual channel to see if you already have a suitable mask, very often this is all you will need.

bob carnie
15-Mar-2012, 11:47
Hi John

I am aware of the Blend If option,,,, but I really never got the concept down and would like to know where you picked up
the knowledge on Blend If.
I believe it could be a very powerful tool in editing.

thanks

Bob

Another method -

If the sky is the only part of the image thats the luminosity of blue you want to edit:

- Create whatever adjustment layer you want to get the sky where you want it
- Option click the layer and select Blend If
- Set Blend If to blend if blue
- Use the blend-if sliders to isolate the shade of blue you want to allow. Option click the slider to break it into two endpoints. How far you place them from one another dictates the smoothness of the blend.

sully75
15-Mar-2012, 13:44
Forgot to mention...it's a black and white image. I'm thinking what I want to do might not be possible. I'd like to make a mask of the darker part of the image. Like if I were to make is super contrasty, so it's all the foreground objects as black and then the sky is white (including clouds), then I can use the mask to tone down the sky without touching the foreground. There's a chain link fence and a lot of wires, so it's not easily maskable otherwise.

I think this image (I had high hopes) might be going into the ol' shitpile.

Daniel Moore
15-Mar-2012, 14:34
How about posting a test jpg?

Greg Miller
15-Mar-2012, 14:51
Forgot to mention...it's a black and white image. I'm thinking what I want to do might not be possible. I'd like to make a mask of the darker part of the image. Like if I were to make is super contrasty, so it's all the foreground objects as black and then the sky is white (including clouds), then I can use the mask to tone down the sky without touching the foreground. There's a chain link fence and a lot of wires, so it's not easily maskable otherwise.

I think this image (I had high hopes) might be going into the ol' shitpile.

The color range selection method will still work with B&W as long as there is sufficient contrast in the tones you want to select (and not select). If necessary, you can copy your pixels layer and then add contrast to that copy layer, make your color range, apply the selection as a mask to a curve layer, then delete the copied layer.

John Rodriguez
15-Mar-2012, 16:49
Forgot to mention...it's a black and white image. I'm thinking what I want to do might not be possible. I'd like to make a mask of the darker part of the image. Like if I were to make is super contrasty, so it's all the foreground objects as black and then the sky is white (including clouds), then I can use the mask to tone down the sky without touching the foreground. There's a chain link fence and a lot of wires, so it's not easily maskable otherwise.

I think this image (I had high hopes) might be going into the ol' shitpile.

Super easy. Use the same Blend If flow I outlined but instead of using blue use the gray values.

John Rodriguez
15-Mar-2012, 16:52
Bob, the book that explained it to me best was Dan Margulis' Professional Photoshop: The Classic Guide to Color Correction. It's the only PS book I'd consider a must-have. It's not a cook-book, but rather explains the how and why of color spaces, contrast enhancement, curves, sharpening and blends.



Hi John

I am aware of the Blend If option,,,, but I really never got the concept down and would like to know where you picked up
the knowledge on Blend If.
I believe it could be a very powerful tool in editing.

thanks

Bob

Preston
15-Mar-2012, 18:15
I'd like to make a mask of the darker part of the image.

Tony Kuyper's Luminosity Masks will do this easily. They are Photo Shop actions. I use them extensively. They are not very expensive, and are worth every penny. Tony has also created excellent tutorials for these masks. Tony's Masks (http://www.goodlight.us/writing/luminositymasks/luminositymasks-1.html)

--P

sully75
16-Mar-2012, 07:04
How about posting a test jpg?


Here it is:
https://lh4.googleusercontent.com/-DxvZlkUE3RE/T2M5_aBDltI/AAAAAAAABIg/5SDhqephWQE/s912/img122.jpg

I had pretty high hopes for this image, but I think it's pretty much a piece of crap at this point. I have a backup negative...I'm thinking maybe more development? It's flat. Dead in the water.

John Rodriguez
16-Mar-2012, 07:42
Sully, I'm not sure exactly what you want to do with the sky, so I just added some contrast to it. However, you can use the same technique using any adjustment you choose. This took me about 30 seconds using a curves layer and Blend If, no masks or selections required.

http://i41.tinypic.com/vpyfpw.jpg

Greg Miller
16-Mar-2012, 12:39
Here's a version using a color range selection - your original on the left; my version on the right with the sky darkened. . It just took a few seconds. The chain link fence doesn't have enough resolution in the web file to woprk with, but should work fine with a full rez version.

70287

And that looked too flat so I added some contrast.

70289

Daniel Moore
16-Mar-2012, 12:43
I'm no expert, I don't even develop my own film anymore, but more development may help with the midtone separation a bit too. In the jpg there's no detail in the fence where it overlaps the sky, hopefully in your original there is and you can treat them individually. Just the same, I had a play, but mostly to get a more interesting tonal range.
70288

sully75
16-Mar-2012, 14:56
Thanks guys. I ended up with similar results to yours...it's just not the image I was hoping for. I'm not totally sure what that image was, but this is sort of reinforcing my need to get a little bit more control with film development. I don't think burning in the sky is going to do it. But...I'm glad at least I'm reminded how to make masks, as this was something I used to use a lot.

Thanks again
Paul

sully75
16-Mar-2012, 17:46
PS sorry for wasting everyone's time on this image.

What I was hoping for was a medium strong cloudy sky, and for a moderately contrasty foreground with excellent detail throughout. I did not want the image to be super contrasty, just contrasty enough to be super detailed, with a smooth range of tones.

I guess I got the smooth range of tones but it's super flat. If I try to boost the contrast it turns into some expressionist mess. So...I don't know. Longer development time?

Should I have used a red or orange filter to bring in the sky? I don't actually own one as of yet.

Daniel Moore
16-Mar-2012, 19:15
You probably have a polarizer, that's a very good start. Ken Lee has something to say on the matter (http://www.kenleegallery.com/html/tech/index.php) as well, read down to Polarizer + Yellow Filter for a Natural-Looking Sky.