View Full Version : Contrast Masking


DannyRaphael
04-21-2002, 08:45 AM
Easy Contrast Manipulation Technique

In a Photoshop book I was reading there was mention of using a contrast mask to solve a particular problem, but no further detail was provided on what a contrast mask was nor how to create one.

Hadn't heard of a contrast mask before, so I did a little surfing to see what I could find.

The Mother of all Contrast Mask Tutorials
After using the technique to create a CONTRAST MASK (http://www.luminous-landscape.com/contrast_masking.htm) detailed at this site, I was very impressed by the subtle-to-intense contrast results that can be achieved, plus some subtle sharpening as well.

The last step is a Gaussian Blur, which is used (in effect) as a tuning knob.

My only suggestion would be to duplicate the subject image beforehand to enable easy side-by-side comparison while tuning with Gaussian Blur.

Instead of the generic desaturate command, one might substitute a Channel Mixer adjustment layer set to 'monochrome' for added flexibility.

Will this technique replace Curves?
Of course not. To me it's (now) just another tool in the 'bag of tricks.' Since the effect is applied via a separate layer, in addition to opacity, one can further tune the results with a layer mask or additional adjustment layers of your choice.

Pictures worth 1,000 words
Be sure to check out the "Informative Report" (supplimental site) (http://www.vinberg.nu/photography/articles/contrast_masking.htm) mentioned at the end of the turtorial for some dynamite side-by-side effect-of-various-Gaussian-Blur-setting examples.

Actions, anyone?
This technique begs to be converted into an Action, so one I developed with PS 5.5 is attached in case that floats your boat. It should work with PS 5.x and above.

Happy Photoshopping! :pleased:

DJ Dubovsky
04-21-2002, 09:21 AM
I see what you mean. Big difference. I downloaded it to give it a try. Thanks again. You seem to find some neat stuff.
DJ

DJ Dubovsky
04-21-2002, 06:05 PM
I gave it a try and I really liked what I saw. At first I thought it wasn't anything I couldn't do with a layers adjustment of curves and the effects were similar but there are definate differences that you will see in this example. The first image is the original. The second I ran a curves adjustment and on the third I did the contrast mask action. Note the differences in the sky contrast details and the ground. Even some of the clothing has more depth than the basic curves adjusted image.
Very good tool and I found it is best used on scenic images rather than portraits. Also the finished product comes with a before version and the after version which has the mask on a seperate layer giving you added control over the finished result. You are also prompted to adjust the gaussian blur to eliminate any haloing that may occur and get the best blend possible. Love it!!
DJ

winwintoo
04-21-2002, 06:40 PM
Thank you so much for the tip. I had been working on a very dark snapshot and when I used a curves adjustment layer by itself, the whole photo looked faded to me. This technique fixed it.

I'll be sending in my contribution on May 21 for sure,

Margaret

jeaniesa
04-21-2002, 06:40 PM
WOW! I love what it did to that sky DJ!! I've got a few "washed out" scenery shots that I've been trying to figure out what to do with - wishing there were such a thing as an equivalent a "polarizing lens filter" in Photoshop. I found one technique on the web after an hour of searching, but now I'm going to try this and compare with the other technique I found. Can't wait to try it!

Thanks for the pointer Danny! :D

Jeanie

jerry
04-21-2002, 08:25 PM
DJ

Thanks for the examples. It is really interesting to see the differences between the curves and mask examples. I think we all should stick to the curves adjustment because " THE CIGARETTE MAGICALLY DISAPPEARED WHEN USING CURVES ADJUSTMENT" :D :D :D

Seriously, this is really useful to learn when everything is new to you.

Thanks Danny for sharing the fruits of your surfing.

Jerry :D

DJ Dubovsky
04-21-2002, 08:43 PM
Jerry
:lol: Now how did you see that little tiny missing ciggerette? Boy when you scrutinize you do a good job. :D I had fixed that photo a while back using a curves adjustment and then I decided to clone out the ciggerette. The contrast mask came from the original version. Boy I can't get away with a thing with you guys. :D

Jeanie, that is what the Contrast Mask action did to the sky. That's one of the features I really loved about the action vs the curves.
DJ

Sharon
04-21-2002, 10:41 PM
Danny

Thanks so much for posting the action your created from the Contrast Mask tutorial. It really brought out the shadowed grass in one of my photos. I know I will be using this action often.

Sharon:)

BigAl
04-22-2002, 04:22 AM
Hi Danny,
I was reading there was mention of using a contrast mask to solve a particular problem, but no further detail was provided on what a contrast mask was nor how to create oneYou forgot to search RetouchPro:glasses:

Check this one (http://www.retouchpro.com/forums/showthread.php?s=&threadid=1730#post12674). (And here I can also test linking to a specific post:) )

Contrast masking is really quick and easy, and once you've used it, you end up trying it in all kinds of situations. Luminous Landscapes is also in my Favourites list. :thumbsup:

DannyRaphael
04-22-2002, 07:39 AM
BigAl...

As usual, you're right on the $money$.

Considering I titled this thread "Contrast Masking," I have no idea why it never occurred to me to use "contrast masking" (or " contrast mask* ") as search arguments. That'll teach me to make search arguments a little more generic! :)

I learned something from the other thread and I expect others will too. Appreciate you pointing that one out.

BTW: The "direct link" to the specific post (vs. the thread) worked like a charm. A+ on using that recently debated (and debugged) method.

While messing [again] with the forum search engine trying to figure out how I missed your original post, I found several other interesting tidbits, so I'm itching to do more reading. If I don't get any work done today, it's all due to your inspiration! :D

Oops... Just noticed the clock just rolled past 5:30 a.m. locally. Must be time to put on a new pot of real strong coffee before I mine for more ReTouchPro.com gems.

Thanks again...Have a good one.

DannyR

DJ Dubovsky
04-22-2002, 08:22 AM
Oh that is so funny. :D Call it something else and it looks and works differently. What's that saying? "A Rose by any other name smells....like some other flower" :D I knew I liked that technique I just never seem to recoqnize it when I see it. :lol:
DJ

Stephen M
04-22-2002, 09:16 AM
I am an active member of this Photoshop email/web list:

http://sparky.listmoms.net/cgi-bin/lyris.pl?enter=photoshop

Over a year ago a similar thread was taken to extremes, it ran with the title 'coming out of the shadows' or something...

You too can have the power of masks, blend modes and curves in one edit!

Make your density mask how you like, either by looking for the best of 10 channels or just copy the colour file and paste it into a new alpha channel. Enhance the contrast, perhaps paint out uneeded detail in the mask and give it a bit of a small blur to soften the transitions.

Load a selection off this alpha channel contrast/density mask.

Make a new curves adjustment layer, hold down opt/alt when you click the shortcut icon on the layers palette to get the options up before you create the adjustment layer. Now you can add screen as the blend mode to lighten the shadows in the image - and the curves give more control added to the mask/blend. If the highlights are being lightened, then invert the adjustment layer mask so that it only affects the shadows.

Taken to the next step, you add a third layer...

As things stand there is the original background layer and the adjustment layer/mask/blend doing it's magic - you can then dupe the original background layer again and turn off the view icon for the true flat background layer...then merge visible so that the correction is applied to a dupe layer (now there are only two layers, both in normal mode with the upper layer being lightened in the shadows). Or layer sets could be used with no merge...Now you can change the upper layer/set from normal to luminosity blend mode.

As the screen blend and curves moves will affect colour and tone, when you may only want the brightness changed and not the hue/saturation.

Of course, this is all done after you have set endpoints and performed global corrections - as these are selective edits which may not be needed or may not be as strong when gloabal edits are first applied.

Regards,

Stephen Marsh.

Stephen M
04-22-2002, 09:25 AM
Oops, I forgot these links in my post (free rego required to view) - they are related to this thread and well worth the read, also go to the advanced search and select the Make Ready articles with Dan Margulis as the keyword for the search - there are many old and current articles to be found here, which are not listed at Dan's main site:

http://ep.pennnet.com/Articles/Article_Display.cfm?Section=Archives&Subsection=Display&ARTICLE_ID=130520&KEYWORD=dan%20margulis

http://ep.pennnet.com/Articles/Article_Display.cfm?Section=Archives&Subsection=Display&ARTICLE_ID=135763&KEYWORD=dan%20margulis

More links such as this can be found at my sites links page, listed below.

Have fun.

Stephen Marsh.

jeaniesa
04-22-2002, 09:42 AM
BigAl - What's so interesting to me is that your post came in the middle of a "making shadows lighter" thread, which was something I was familiar with, so it didn't have as big an impact. BUT, when I saw Danny's post - and then DJ's comparisons - in terms of "balancing contrast" rather than lightening shadows (which I realize is the same thing), it just hit me differently and gave me some ideas for photos that I'm dealing with right now. So, I guess that goes to show you that repeating info every so often isn't necessarily a bad thing (esp. with the way my brain works!) :D

Stephen - Thanks for those links. I don't have time to really look at them right now, but I've got your post and those links bookmarked to come back to later today!

Jeanie

sdubose99
05-08-2003, 12:51 AM
This is a super thread, thanks to everyone. I used this to pull detail from the shadows and improve the sky in the pic attached here...

Scott
http://www.pbase.com/sdubose