Keen Graphics Blog » tips + tricks

creating faux HDR effects in Photoshop CS4

ramey — Fri, 21 May 2010 21:46:17 +0000

A designer friend of mine recently wrote to ask me what process was responsible for creating a certain “look” of an image she found on Flickr. I recognized it as a combination of HDR (high dynamic range) photomerge, and some other Photoshop filters and tricks. While I personally think the HDR craze is a little overdone, I’ll address the technique here.

Traditionally, an HDR image is created by merging 3 or more photos together that were taken at different exposures. By doing this, you maximize the details in all elements of the photo; underexposure to grab sky/highlight detail, correct exposure for midtone detail, and overexposure for increased shadow detail. However, taking three identical shots is not always possible, especially when your subject is moving. With Photoshop Camera Raw and a few other tricks, it is possible to imitate the HDR effect with a single photograph.

For this tutorial, we’ll take this photo I took of a dive shack in the Belizean Cayes last year (below).

Begin with a RAW image whenever possible. Open the image in Adobe Photoshop Camera Raw. This is the best place to make major changes to an image without losing pixel integrity. To artificially create the effects of a HDR photomerge, we are going to drastically alter some of the RAW settings. Begin by underexposing the image with the “Exposure” setting (in the “Basic” tab). Next, slide the “Recovery” button all the way to the right, or close to it. This will help retain detail in the sky/highlights. Then slide the “Fill Light” setting to the far right as well to fill in shadow detail. The “Blacks” slider can be adjusted to darken the shadows and give more contrast and depth to your image. The “Contrast” slider should be used to adjust the contrast and give your image a dramatic look. The “Clarity” slider should also be moved dramatically to the right – this helps to give exaggerated edges to your details.

Many HDR images also feature selective over-saturation. I use the “Saturation” and “Vibrance” sliders sparingly, and prefer to use the HSL/Grayscale tab in Camera Raw instead. Screen shots below explain the settings.

Next, open the image in Photoshop. We will now apply some filters to achieve even greater effects.

Start by going to Image>Adjust>Shadows/Highlights. Use this panel to lighten some of your shadow features, and enhance your highlight detail. This will also create a “glow” effect around contrasted elements of the photo, like the shack and the sky in our example.

Next, create a duplicate layer of your image in the “Layers” window. Select the top layer, and go to Filters>Other…>High Pass. Be careful not to overdo it on this filter, or your image will look grainy and too sharp. A radius of just a few pixels should do it, depending on your image size and quality. This will render the top layer into a sort of grey textured image. But we will use this layer to create a combined overlay effect with the background layer.

In the Layers window, go to the drop-down menu at the top of the window (default value is “Normal”). You will see a list of options for blending layers. Depending on the severity of effect you desire, select “Overlay”, “Vivid Light”, or “Linear Light”. You can play with these settings to see which one achieves the look you are after. Once you have applied this effect, flatten your image.

Next we are going to sharpen our image with Filters>Sharpen>Smart Sharpen. Again, a little bit goes a long way, so don’t get too crazy with this setting. But using it wisely will help to give that HDR-sharp look.

Once we do this, we will turn right around and use the Smart Blur filter by going to Filters>Blur>Smart Blur. This will help to soften the image just a bit, without losing detail. It will also help to eliminate any noise you created by sharpening and High Pass filtering.

Now let’s take a look at the final result! Without using 3 different images, we achieved similar results to an HDR photomerge. Ta-da!

Original image (above)

After our Faux HDR process (above)

more on correcting rich blacks for newsprint

ramey — Mon, 16 Nov 2009 15:31:28 +0000

I recently ran into another pre-press dilemma for one of my newsprint clients. Of course the phone call came in the day after my print deadline, while I was in the eastern Utah backcountry. So there I was, standing on a rock, trying to get enough cell reception for a 5-minute phone call. There wasn’t much I could do 1,000 miles away from my office, but the problem was this:

I often use colored boxes or gradient sidebars with black text on top of them. I find it helps give color to the page, and adds some visual interest to an otherwise monochrome copy space. I had never had a problem with these in the year and a half that I have been designing this particular publication. Yet, the printer informed me that this time the black text was overprinting, causing rich black text in the colored sidebars. As mentioned in my previous post on rich blacks, small rich black text is a big NO-NO. Even the slightest misalignment in plate registration can cause the text to become illegible. Below is an example of what the overprinted text came out looking like. In print, it looks blurry and over-saturated.

The first step to correcting this problem is realizing it is there. So, when you are checking your output PDF in Adobe Acrobat, go to Advanced>Print Production>Output Previewer. Hover the cursor over the overset black text. If you have exported incorrectly,it will look like this:

As you can see, the black text is actually built of 100%K, along with the ink blend of the color beneath it. In this case, the ink limits are 200% or higher, and the built blacks will cause my text to be fuzzy or illegible. Fortunately, it is an easy fix. In Adobe InDesign CS4, simply go to the Edit>Preferences menu and select “Appearance of Blacks”. A dialogue box will appear with all of the Preferences menu items on the left, and “Appearance of Black” as the active item. Make sure that the drop-down menu called “Printing/Exporting” reads “Output all blacks accurately”. Then, UNCHECK the checkbox below that says “Overprint [Black] Swatch at 100%”. As follows:

This will cause any overset black text to knockout the ink below it, instead of adding 100% to the existing color ink blend. Now simply export as you usually would, and double-check your ink in the Acrobat Output Previewer. Ta-da!

There you have it. A simple step you can take to make sure your overset black text comes out looking crisp and legible. Hope this simple tutorial helps you!

Photoshop brush tricks

ramey — Sat, 12 Sep 2009 12:52:15 +0000

Okay, I feel kind of silly.

I never really liked Photoshop brushes. I felt they were rather limited in scope, and it was difficult to get the effect I wanted. I ended up doing a lot of rotating of the image, a lot of copying and pasting and free transforming.

And now I find out all that work was for nothing.

Adobe, being the geniuses that they are, include an entire options window for brushes. I noticed it before, but never really explored it fully. So, I’m passing on this incredibly simple tip to you…

Window>Brushes produces the Brushes toolbox window. Click on “Brush Tip Shape” (the cleverly hiding option without a checkbox) at the top of the Brush Preset menu list on the left hand side of the window. And ta-da! Here’s what you get:

Using this option panel you can rotate the brush to acheive the effect you want, as well as edit the spacing of brush strokes. Pure gold. And so simple…

Amazing that a person can use Photoshop for 11 years and still learn new things every day. Ha.

Enjoy!