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Asking you photoshop experts for advice - Normally I advise MYSELF to RTFM, but searching through online tutorials and PS books has not provided much specific help.
I frequently want to separately adjust exposure in distinct regions of the image, for example when there is an overexposed sky/ underexposed foreground:
My attempts generally involve using quick selection or magnetic lasso to select the foreground, followed by adjustment of foreground levels and/or apply curves, then invert the selection and repeat for the background:
However, as seen above, there are usually unwanted edge effects. I have experimented with various ways to improve this, feathering the selection edge, shifting the selection edge, etc, but not achieving what I want. I have also played around with layers, but did not produced anything better.
This SHOULD be a FAQ - doesn't EVERYONE need to do this? But so far I find tons of tutorials on bulls--t stuff like replacing your "bad" overexposed sky with a nice uniform blue!
Any advice or pointers appreciated.
To soften the edge effects you need to use a small blur tool and go over the edge areas. I would also suggest you look into a fuzzy select tool for the first step.
Here is how I do it:
Try the highlights, shadows, blacks, and whites sliders. You may need to adjust the brightness a bit to get the overall effect you want. Here's a quick'n'dirty example I just did using NX2 on a JPG (a scan from B&W film). It's not perfect but you get the idea.
Hope this helps
Try a luminance mask on a curves layer, check out You Tube for some great tutorials, also you can invert for shadow regions
Similar to Dave R, I use one or more curves adjustment layers with shadow masks to ensure the curves only affect the area to be treated. When painting on the shadow mask, use a soft, wider radius brush and perhaps several brush strokes using different brush transparencies so there is a gradual transition. I haven't yet looked at Chris's explanation, perhaps that is better.
I understand you can only get pressure sensitive brush strokes if you use a graphics tablet instead of a mouse. Photoshop applications are input-device aware and the tools available change once you start using a graphics tablet. I use an Intuos 5x7.
However now I use LR4 for this sort of processing as I find it easier and better. Still have to do extra pp in CS4 occasionally - but not very often.
Hope this helps,
I will use layers, layer masks, and a color overlay style.
I dupe the image, apply a white layer mask, hide the original layer, and start painting black into the mask, to remove elements I want to remove from the duped layer. Because I'm using a mask, it's non-destructive.
When it comes to tricky borders, I'll use layer styles to apply a color overlay to the duped layer: some dramatic color like bright red or green, something that stands out. I'll apply it as a color dodge or screen or something, at a low enough opacity that I can see the layer details, but the layer as a whole is still quite distinct from the background.
Then I turn on the original layer, and start painting in the duped layer's mask again. Now I'm seeing the background, and the foreground, and I'm using the color overlay style to see them distinctly. Now I can paint in the layer mask very accurately, to achieve perfect borders between the two layers. The layer style can be turned on and off at will, of course, if you need to see things better.
Then come the adjustment layers to do what I want to do to change the actual image.
Depending on selection tools is often tricky: borders are seldom awesome, and it can be annoying to clean up the bad choices selection tools make. Sometimes I will use selection tools to help with the mask work.
There are always some nice tricks in PHotoshop. Here is one for reducing contrast in an image .....try the following.
1 Duplicate the layer
2 Pull the saturation slider to zero on the duplicate layer so it becomes black and white (do not use convert to monochrome - this does not work as it gets rid of the color channels totally)
3 Invert the duplicate so it becomes a negative image
You now have a mask of the original.
4 Now you need to experiment a bit. Apply a Gaussian blur - the strength depends on the size if the image. Experiment between 8 up to 35 pixels. 15 is not a bad place to start. Be aware that you cna get some odd artifacts if you use too much or too little so be prepared
5 Now apply a blending mode - the best ones to try are overlay or soft light. Other do not work as well or at all.
6 Adjust the opacity of the duplicate layer as desired (if the effect is a bit too strong) and when happy, flatten to a single layer if you wish.
This sequence of steps will reduce contrast in an image to a considerable extent. It will make lighter areas a bit darker and darker areas a bit lighter. But I have found it struggles where the contrast in the original image is extreme. Never the less its an easy way to mask so as to reduce excessive contrast in many situations but you do need to experiment a bit.
The main variable is the amount of Gaussian blur so apply this last in the sequence (before the blending mode) so you do not have to back track too much if you need to change it. If you are not happy with the result you can just backtrack to the Gaussian blur stage and try a different blur strength. Another trick you can try when you desaturate the duplicate image is to increase its contrast so that the mask is more contrasty. This will give a stronger effect in the final image.
Once the image has an acceptable amount of contrast you can apply other edits to the image in photoshop.
cheers Good luck
GLOBALLY: First you try to get the right exposure range using Highlights, Shadows, Contrast and Curves in Lightroom. Shooting raw, the latest sensors have a huge dynamic range, so you have a lot of room to get the overall tones mapped the way you like. The D7000 and K5 raw files are extremely malleable. Raw files from previous generation sensors are usually good, but you don't have as much leeway if you didn't expose well.
LOCALLY: Artistically, you frequently want to make local adjustments to darken or lighten certain areas. Ansel Adams didn't just snap a picture of storms over Yosemite, he used dodge and burn extensively. The great thing with Photoshop is using layers so your original file is not changed.
Chris Crawford's tutorial shows a non-destructive way to choose an area and selectively modify lighting.
Search for Google Dodge Burn, and you will find many tutorials. This one is pretty straighforward: Markus Hartel (http://www.markushartel.com/blog/learn-from-markus/non-destructive-photoshop-dodgeburn) . Bair Art (http://www.bairarteditions.com/pages/tutorials/photoshop/exdandb.html) is also very clear:
To do this go to Layer/ New/ Layer. When the New Layer pop-up window appears, select the Mode and choose "Overlay" Then check the box: Fill with Overlay - nuetral color (50% gray) and click "OK." ...
Begin by setting the color palette to the default colors of balck and white. This can either be done by clicking on the default icon, or by typing "d" on your keyboard.
Now select the brush tool (also accessed by typing "b"). For burning use black as your color, and white for dodging. We suggest you lower the brush's opacity down to 20 - 60% depending on your taste (remember that you can always lower the opacity of the entire layer later, and you can erase the paint whenever you want).
If you have the brush's opacity down to around 20%, each pass of the brush will be almost inperceptible, and no matter how many times you pass over the same area, the paint will not increase until you let up on the mouse and depress it again.
I like to go a little heavy and keep my opacity above 50%. This way I can really see where I have painted. Then I go into the layer's opacity and bring it back to the level I want. My coworker, however, likes to use 20% and make fine-tuned passes. Find your comfortzone and paint away!
NON-DESTRUCTIVE LAYER MASKS ARE EXTREMELY USEFUL.
Local adjustments via masks can be done with many photoshop tools, not just dodge and burn. For dozens of very complete and interesting video tutorials on local adjustments, see Craig Tanner's weekly critique (http://www.tmelive.com/index.php/articles/3.html). He might do five or ten layers to adjust levels, contrast, color casts. He also discusses composition, and why you would do the adjustments. THIS ONE (http://www.tmelive.com/index.php/articles/view/715/3.html) is very good on color adjustments.
Folks, thanks so much for the collective wisdom, especially Chris's very helpful online tutorial.
While the photo is still not to my liking (and may never be!), the edge issue is much improved, and I expect could be made better adjustments to the blur radius:
nice & good technique in your post.
Many interesting ideas, always useful to know something more. Thanks.
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