Post Processing Tutorial, 2 – Quick Overview, Color Contrast Adjustments

Overview, details to follow in a later post

Previous post processing (PP) tutorial overview posts –

Here, we’re looking at step #3 in this sequence of PP adjustments

  1. White Balance
  2. Highlight & Shadow Recovery
  3. Color Contrast
  4. Tonality

(click any image to enlarge)

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Thus far we’ve considered the following steps –

Our image as captured in-camera (RAW),

followed by the next image which shows the effect of  a PP white balance (WB) adjustment,

followed by the next image which shows the effect of  a PP shadow/highlight recovery.

It’s important to realize that the result shown in the final image could have been achieved in-camera at capture if we had taken the shot –

  • Nikon only – Active D-Lighting on and set to Extra High, or
    • Any camera – with an exposure compensation 2/3 stop higher than actually used,
  • Set our WB very slightly cooler (most cameras offer a fine-tuning option for each preset)
  • There will be some minor variations from camera to camera due to differing white balance processes, but the end result would be essentially the same.
  • Take-away message – get it nearly right in camera and a few post-processing tweaks is all that it takes.

It’s equally important to realize that none of the actual camera settings (WB & exposure) can be changed directly in PP (to achieve the same result as would have been had at capture) if we did not shoot in RAW. The improvement in this image was relatively minor because I strive for perfection in-camera – but make a mistake leading to a bad capture and you may be in trouble if you didn’t shoot RAW. A word to the wise….

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At this point we have achieved an image with nearly perfect colors, as a result of the initial WB step, and nearly perfect exposure as a result of the previous shadow/highlight recovery step. This was all done by simply changing our camera settings in PP to what they might have been at capture. What’s next?

Most digital images suffer from a lack of contrast in two areas (depending on the subject matter and the camera make/model) –

  1. Color (think hue)
  2. Tone (think brightness)

So why’s that a problem? Images that lack contrast are flat. They lack life (or as some say, Pop!). In the extreme, in a flat image colors within an area (sky, surface, etc.) appear to have been painted with a single uniform color from a can instead of the natural variations and gradations that reflect reality.

In this post we’ll look at color contrast adjustments, and do the same with tone in the next. These adjustments do not depend much on whether you shot in RAW. Start with an image that has correct color and good exposure – RAW, JPEG, TIFF, whatever – and you’re set to go.

Although there are many ways to tackle the contrast issue, since this is an overview post focused on showing the effect and not the mechanics of “how” I’ll use Nik Software’s Color Efex Pro (CEP) plug-in for NX2 – specifically the “Contrast Color Range” filter. Note that this adjustment is also available in NX2 without the plug-in.

I discussed the programs I’d be using, and the rationale for using them, in this post in case you missed it. As an additional note specifically about the CEP adjustment I’m about to demonstrate, recognize that anything shown here can be done in Photoshop. CEP is available as a PS plug-in. As such, even without the plug-in, the CEP result can be done directly in PS – assuming you have the time and knowledge.

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This is CEP control panel for color contrast adjustments. The main (starting) control is the top one labeled Color. It has a range of 0 to 360. Its effect depends on the image & its colors. The effect for our image is as follows –

Set to 0 we get the next image (washed out colors)

and set to 360 we get this next one (over saturated)

And twiddling the Color slide and settling on 229 give us one where the color contrast is almost “just right”

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When I say almost, there are shadows & highlights that aren’t right. Since we spent the entirety of the previous step (post) fixing just that, we need to do something about it. The problem is illustrated in this next view of the Color Contrast control panel which includes a histogram. It shows the extent of the problem by specifying the % of pixels with

  • 0.2% Highlights with no detail (specular = pure white)
  • 0.2% Highlights with detail
  • 2 % Shadows with no detail (pure black)
  • 2.4% Shadow with detail

and we want to correct the “no detail” problems at a minimum.

and we can make the corrections directly from the above panel simply by moving the “Protect” slider to the degree necessary.

Doing that, plus reducing the Opacity via this same panel to reduce the strength of this adjustment, we have the next control panel followed by the resulting image. Note, that I chose not to protect everything (make all problems = 0%). The are actually white and black area in the image and I wish to retain them – but with a slight amount of detail.

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So there we are after three steps. To recap our efforts thus far, here are the images beginning with the original capture and ending with the one above.

Our image as captured in-camera (RAW),

followed by the next image which shows the effect of  a PP white balance (WB) adjustment,

followed by the next image which shows the effect of  a PP shadow/highlight recovery,

and finally, the results of the Color Contrast adjustment step –

If you’re interested in the histogram progression for the same four images (you should be), here they are –

Original>>

After WB>>

After shadow/highlight recovery>>

After Color Contrast improvement>>

In the previous step, shadow/highlight recovery, I noted that at the end of the step some red highlights were slightly blown – as shown by the next to last histogram. Further, I noted that it wasn’t a big deal at that stage and could be corrected easily later. This is one of the possible “later” steps – note the change in the final histogram where there’s no more red climbing the right hand wall..

From step to step the changes are mostly small and subtle, but the cumulative difference is noticeable as shown in this side by side image (click to enlarge) – and we have further improvements that can be made. The top image is as captured in camera and the bottom shows the cumulative effects of the adjustments made thus far – WB, Shadow/Highlight Recovery, and improved Color Contrast.

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A final thought – although the color contrast changes in this step were applied throughout the entire image, this didn’t have to be the case. In fact, later adjustments work best when applied selectively. There are many approaches & techniques for applying things only to some areas and not others. We’ll look at some of those in later posts. We see that many require features not available in all PP programs, or they require a skill set that is hard to learn and to apply, or the results aren’t realistic – or all of the above. Selective application of adjustments is a feature that sets NX2 above almost every other program out there. They use a patented feature called U-Point which allows you to do in seconds what will take minutes to hours (if it can be done at all) in other programs. This feature alone is worth the price of admission IMO – even if you shoot non-Nikon and use NX2 just for the post processing required after RAW conversion. You can read about U-Point here or Google U-Point.

Here’s an example of the mask that is generated in a second if I had decided to apply the Color Contrast adjustment only to objects in this image that shared characteristics of one of the foreground orangish leaves. The control point has been applied to a orange leaf on the foreground rock (it’s above the cursor pointer that I left as a marker for you to see – click to enlarge and see this detail). It was applied simply by pointing at the leaf and clicking – thus U-Point. More pointers can applied (both + which adds the adjustment and – which protects against the adjustment). This mask is what you’d need to create yourself manually in any other program  (assuming the program even provides mask options) – good luck in doing that.

White areas in the mask will have the adjustment applied full strength (as specified by my settings), black will have no adjustment, and shades of gray will be affected in proportion to their lightness/darkness. Total time to make this mask 2-3 seconds (automatically, done for every adjustment with no special tricks or options – it’s just there). Time in Photoshop – many, many times this long and it won’t be this sophisticated.

2 thoughts on “Post Processing Tutorial, 2 – Quick Overview, Color Contrast Adjustments

  1. Very interesting so far. I’ve always been a bit scared of Contrast Color Range, mainly because I never really understood what it did, or how to control it. But it can certainly make an image “pop” when used appropriately.

    • I started using it regularly about 6 months ago. I now do the 4 steps outlined in this overview with Color Range in the number three position just as shown here. I don’t normally add much “pop”; it depends on the image and how drab/flat it is. Usually not much is needed and too much looks like, well, too much.

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