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trink408
3-Jul-2008, 11:04
Looking for some advice/tips on how you use photoshop to contrasty images.

I've following a technique I found on Luminous Landscape called contrast masking with varied results, wondered if there were other techniques??

Any advice is greatly appreciated.

Thanks,
Kevin

Peter Mounier
3-Jul-2008, 12:56
Here's a technique that works well for me. First make a Highlight mask. Do that by: #1) Click on the "channels" palette (to bring into view).
#2) Click on the RGB channel while holding down the "option" and "command" keys.
That selects just the highlights in the image. Click again (and again) to select more of the highlights in the image. The more times you click the RGB channel while holding down the keys, the more highlights you will select, until you've selected way more than just highlights.
#3) Select "Inverse"
Now you have just the shadows selected.
#4) Adjust the shadow contrast with levels or curves.

This works well if you have good highlight detail. You can't fix blown out highs.

Once your shadows are adjusted and deselected, you can go back to the channels palette and select the highlights again. With the highlights selected, add the shadow mask selection.
Then select inverse. Now you should have a selection that excludes the highs and the lows so you can adjust the contrast on the midtones.
Now your shadows and midtones are adjusted.
Select the highlight mask again and adjust just the highlights.

Peter

Donald Miller
4-Jul-2008, 08:16
Kevin, I am not sure what you are trying to accomplish. There are different tools for different reasons. Maybe if you could give a little more information, you might get more pertinant answers.

Normally masking (whether traditional or digital) is an attempt to rescue an image. I don't know whether this is what you are trying to do or not. There is one exception to this that I have found and that is luminosity masking. Luminosity masking allows one to optimize local contrast in specific tonal ranges.

Which version of PS are you using?

Brian Ellis
4-Jul-2008, 09:51
I very quickly skimmed the Luminous Landscape article so I may have missed something. But it looks like this article was originally written in 2000, before the Recovery tool in CS3 Camera Raw was around and maybe before the Highlight/Shadow adjustment was around (I forget exactly when it first appeared in Photoshop). In any event, the Recovery slider in Camera Raw does a good job of recovering detail in highlights and the Shadows adjustment in CS3 does pretty well with blacks. I seldom use the Shadows adjustment myself but you asked for other methods and that's one. My own preferred method of adjusting local contrast is to make a snapshot in the History palette, adjust the contrast with levels, curves, or whatever, and then paint it into the desired area with the history brush.

Ben Syverson
5-Jul-2008, 09:44
Are you wanting to increase or decrease contrast?

I usually find that a subtle "S" curve (in Curves) can solve any contrast issues one way or the other. I don't like to do localized dodging/burning/contrast adjustment, but that's just me...

Lenny Eiger
5-Jul-2008, 10:20
Looking for some advice/tips on how you use photoshop to contrasty images.
Thanks,
Kevin

I use masking on almost every image. There are many ways to make masks. Channel masking is a great start, Select by Color Range also. Then its great ( I think its essential) to have a Wacom tablet to refine the masks one makes. There are all sorts of techniques to add and subtract masks from each, etc., etc. It allows you to control specific areas of the image - with far more control than making a print in the darkroom.

It is a tool to use with adjustment layers to create a superb print. It isn't just to recover or fix things. You can fix blown out highlights sometimes, IMO, it just depends on how far you blew them out. You can't make up detail, that's for sure...

Lenny

Bill L.
5-Jul-2008, 18:17
I occasionally used a contrast masking technique similar to the one in the LL article. Since I've gotten a version of the PS with the shadow/highlight command (I think it was originally in CS?), this essentially performs the same functions, only with much more control. I suggest if you try it, use a duplicate layer to perform the shadow/highlight function on. That way you can vary the opacity of the layer to "season to taste", and put a mask on the layer so that you can paint in the areas you want the effect.

Cheers!
Bill

Kirk Gittings
5-Jul-2008, 19:00
Looking for some advice/tips on how you use photoshop to contrasty images.

I've following a technique I found on Luminous Landscape called contrast masking with varied results, wondered if there were other techniques??

Any advice is greatly appreciated.

Thanks,
Kevin

To keep it simple Try the "luminosity mask" actions of Tony Kuyper they are very effective and easy to use. I use my own version of them on almost every serious image that goes to print:
http://www.goodlight.us/writing/tutorials.html

trink408
7-Jul-2008, 07:10
Thanks for all the tips everyone, I have some things to read and test out.

I'm using PS CS3, so I will have to look at using the shadow/highlight tool and see what that does.

I'm still new with PS, so I have many things to learn. I'm not famliar with making a mask and painting it in. I do work with layers, but I'm sure I have things to learn working with those as well...

Kevin

Lenny Eiger
9-Aug-2008, 12:17
I'm not famliar with making a mask and painting it in. I do work with layers, but I'm sure I have things to learn working with those as well...
Kevin

Masking is the key to most of the control most of us need. However, I noted the Tony Kuyper site with the "luminosity mask" when I read this earlier in this thread and finally checked it out today.

It is way simpler than all that. This is just channel masking with a fancy name. All you have to do is duplicate a channel and you have a mask. Then you can work on it with Levels, Curves, paint it with a brush, paint using overlay, use a lasso to fill in large areas (without touching any edges), whatever you want. Make 6 of them if you like.

When you are ready, you command click on it and it makes marching ants. Then you create an adjustment layer (at which point you can toss the alpha channel). Its a great way to select things... it's the basics... you don't need an action, or a product from anyone to do this.

Of course, the fun part is adding and removing masks from each other to create one for the sky, one for the lower area, etc.

Lenny

Vaughn
9-Aug-2008, 21:16
Sandy King's article in the latest ViewCamera Magazine on two-bath neg development would be a good read for you. He outlines a method of getting good negs of high-contrast scenes specifically for scanning. Even with PhotoShop, starting with the best possible neg will give the best results (and be a lot easier to handle).

There is also a good article on various types of masks in the same issue.

Vaughn