Add Two Steps

Recently, we have seen an increase in photographers using the High Pass filter in Photoshop to add edge contrast and texture detail to their images.  This is a cool technique but when you use the filter remember to add two more steps; desaturate your layer before applying the High Pass filter and always target your filter effects with a mask.

Capture3.jpg

You may have seen or heard many photographers talking about how they sharpen only on the Lightness channel in L*A*B* or they make sure to change the blend mode of their sharpening layers to Luminosity or they use the Fade option with a Luminosity blend mode change.  There are many good reasons to make these switches and we suggest you use them in your sharpening or contrast boost workflow.  For the same reasons, when you use High Pass desaturate.

It is a common misconception that when you run the High Pass filter you are left with an image that is baseline 50% gray and only shows brighter or darker tonality at the edge contrast and texture detail.  Instead, High Pass may retain color information from the original image.  This can lead to color shifts or colored fringe along a high contrast edge similar to haloing.

Capture4.jpg

Notice the

remaining color.

Our workflow is to copy the background layer or stamp visible if you have a multi-layer document and then desaturate via Image>Adjustments>Desaturate this can also be executed with the keyboard shortcut of CTRL+Shift+U for Windows or CMD+Shift+U for Mac.

Capture2.jpg

For those who want to play or have more control you can

  • Run a Black and White adjustment instead and modify the tonality of the color arcs.
  • Use multiple layers of High Pass set to different radii.
  • Leave the color in your layer in order to generate a color boost. Watch out for fringing!
  • Use the filter on a Smart Object so you can make changes.
  • Invert your filter layer to decrease contrast and texture detail.

The second misconception is that areas that appear to be smooth after running the High Pass filter are not. Make sure to use a mask and target the filter effect to only those areas that you want to modify. In general, LIGHT does not recommend enhancing the edge contrast or texture detail on the following:

  • The sky especially blue sky.
  • Areas of constant color or tone.
  • Flowing water.
  • Out of focus areas.
  • Human skin especially female skin.
Capture5.jpg

Fiat Lux!

How to Get Rid of Chromatic Aberration / Jane Conner-ziser

Chromatic Aberration, in simple terminology, is when the colors in a digital file do not line up correctly and you can see colorfringing” around the edges of objects in your picture, mostly in places where a dark object is next to a light one. This is caused when the lens fails to converge all of the colors to a single focal point due to different wavelengths – and it can be exaggerated if there is movement during the capture process.

Sometimes chromatic aberration occurs only in specific areas of a file, but sometimes, like in this sample, it occurs throughout the image and correcting it can become a big job!

Img_01.jpg

SO, in this article I will share with you the most common options for getting rid of chromatic aberration, starting with the easiest; Adobe Camera Raw or Lightroom.

Both ACR and Lightroom have options in the Lens Correction Panel that address chromatic aberration.

Img_02.jpg

If the aberration is slight, all it takes is some visual adjustment of the sliders and choosing the defringing option that provides the best visual correction. Finite. Done – but it didn’t work on this image because the aberration is too severe.

Img_03.jpg

The next option is to consider that the problem is that the color channels are not lining up correctly and perhaps there might be an adjustment that can be made in Photoshop to realign them. There are two options for this. The first involves opening the Channels Window, clicking on a color channel plus the visibility icon (eyeball) on the RGB channel and using the Move Tool to realign the color channels, matching the edges of your image.

Img_04.jpg

This worked well in some areas, but not in others. It is possible to distort (transform) the separate channels … but you must keep in mind that image clarity is easily affected – which brings us to the second color channel option, changing the Image Mode to Lab Color first (Image / mode / Lap color) in order to separate the luminosity (detail and value) of the file from the colors. Once the adjustment has been made, return the file mode to RGB.

Img_05.jpg

Unfortunately, this option didn’t do very well on this file either! We will be forced to take care of this the old fashioned way – correcting it by hand, one edge at a time. It’s going to take longer but the results will be perfect – here is how you do it:

Make a New Layer and change the Layer Blending Mode from Normal to Color. Choose the Brush Tool and set the opacity to 50%; use a small sized brush (this image was done with the brush size at 5 pixels, just large enough to cover the discolored edges). Hold down the Option (Alt) key to choose the neighboring color, then simply color over the one you want to change. Apply a few coats, reselect, and continue throughout the image. It is faster than you think and the results are worth it!

Img_06.jpg

I dropped in a neutral gray layer under my paint and am showing the color layer in Normal Mode so you can see my work:

Img_07.jpg

The total of my work looks like this:

Img_08.jpg

And the detail looks like this:

Img_09.jpg

The job took just under an hour once I decided upon my strategy, and you can see how important it is to know your software! Options are important when you’re doing real world retouching because you want to get your work done as quickly as possible, but no two images are alike. Always start with the quick option, but learn a variety of ways of doing things so you won’t find yourself stumped on an important image that just has to be better.

This image was going to be printed as a 6 foot mural, part of a three image display with two other images that did not have the same problems as this one so it was really important that the work was perfect and would hold up to the enlargement. I’m so happy to say that everyone was pleased! Awesome!

Thank you for letting me share this project with you!

Jane Conner-ziser is an internationally recognized expert in ACR, Lightroom, Photoshop and Painter. She is an author, portrait retouching artist, painter and instructor living in Ormond Beach, Florida. She has been actively involved in professional photography for over 25 years. Contact Jane at Light Workshops lightworkshops.com or through her websites www.janeconner-ziser.com and www.jczphotographics.com

The Dreadful Banding, Bane of the Photo Printer and How to Get Rid of it!

by Lee Varis

Most photographers who print their work encounter this sooner or later. It often rears its ugly head in clear sky gradients – the dreaded banding, posterized tonal gradients that break into discrete bands that destroy the smooth appearance of the sky. This is a "digital" artifact that is mostly blamed on 8 bit files! The fact is that banding in a print can often result even with high-bit depth files during the conversion to the printer profile for output. The problem is hard to predict or pre visualize and this can result in wasting expensive paper to discover that you have to "fix" something in the file.

The following image demonstrates the nature of the problem.

sky

It looks smooth doesn't it... but, if we look at the individual channels maybe we can spot the problem...

sky red channel

The green and blue channels don't really show anything but here in the red channel we can just barely see that there might be an issue. It's subtle though so we can't really be certain that there will be a problem. The issue of banding in skies, or any smooth gradient for that matter, has been around as long as digital imaging has existed and there have been numerous attempts to solve the problem. Back in the day, when real high-end imaging was only possible using Scitex and Quantel Paintbox systems the solution was more or less the same as it is today - one has to add noise in some fashion or another to break up the bands. Outputting a file only to discover that there were bands was quite expensive so many shops resorted to adding noise as a standard procedure before outputing anything. However, adding noise often resulted in a gritty appearance and if it wasn't necessary it wasn't desireable.

One of the original Quantel Paintbox engineers, Ed Manning, invented a technique to pre visualize the bands and old timers like myself will still refer to this as "Ed's Curves" – Now its mostly referred to as "solar curves." This technique is still useful as part of our strategy to eliminate bands. Begin by duplicating the background to a new layer...

Layer Panel with Curve Adjustment

To setup "Eds Curves," make a new Curves Adjustment Layer at the top of the layer stack and, once you are in the Adjustments Panel, place multiple points on the Curve...

Points on Curve

Now, pull the points up and down so that you end up with an extreme sine wave sort of thing like this:

Extreme Wavy Curve

The result puts all the tone transitions on a mostly vertical segment of the curve so we have a lot of contrast between tones – we also have a fairly psychedelic image...

psychedelic sky

Despite the rainbow color the image shows very obvious sharp ridges running through the sky. We can leave this temporary Curves adjustment on to help visualize just how much noise we need to eliminate the ridges. Select the duplicate layer and run the noise filter: Filter->Noise-> Add Noise...

psycho sky with noise

The idea is to use enough noise to completely hide or obscure the ridges. This is the traditional approach that most prepress professionals use. The problem with this approach is that often quite a bit of noise is necessary and it can lend the image a harsh look...

Noise in sky

Sometimes this will not look as bad in a print but there is a better approach. Instead of using the standard noise filter, use: Filter->Brush Strokes-> Spatter...

Brush Strokes

The large filter dialog allows you to select multiple artistic filters intended for creating painterly effects.

Filter Dialog

For our purposes, we want to have a high "Spray Radius" and a Smoothness setting of "1"

Spatter Settings

This filter is much more effective in smoothing out bands in a gradient than simply adding noise. The only trick is in masking off the dark "spatter" of the non-sky elements at the horizon. For that we can turn to the Blending options dialog...

Blending Options
Blending Options dialog

Setup the "Blend If" sliders for the Blue channel as shown above - the idea is to blend through the dark, non-sky tones to reveal the "un-spattered" image in the Background. Sometimes you can get away with only using the slider in the top layer – here I've used both to get a cleaner image. Often you'll have to do a little bit of masking for final cleanup – add a layer mask to the "Spatter" layer and mask out the dark speckles with black.

The final result is smooth with less obvious noise...

Smooth Sky

Compare this with the original and with the noise version! Spatter breaks up the bands with diffusion instead of adding light and dark noise so there is no grittiness and no bands. At this point you can throw away the Curves Adjustment layer and print with full confidence that you have vanquished the dreaded bands forever!

Remember "Ed's Curves" and use them whenever you have the slightest suspicion that banding may be present and you can clearly visualize the 'bands" before they bite you in the butt...

Learn more incredible digital imaging techniques from Lee Varis at the California Photo Festival, October 12-16, 2011! Lee will be teaching all 5 days during the festival, discussing topics like The Digital Zone System, Mastering Exposure, High Speed Camera Techniques and more!

Click here to see Lee's full festival schedule.

Embrace the Group

As many of you know the power of Photoshop is found in the layer.  Taking that a little further, it is found in the combination of many layers to achieve just the look or design you are going for. 

Some users are hesitant at first but soon find themselves adding layer after layer in order to perfect an image.  As I walk around the classroom looking at people's work it is not unusual to find images with 25+ layers! 

With all those layers, things can get a little bit confused and cluttered.  We recommend two simple tips to help keep everything logical and organized.

A mess of layers.

1) Name every layer.  Of course, Photoshop does this for us but the auto generated layer names do not always tell us exactly what the layer is doing.  Try to name each layer with something simple that tells you immediately what the layer does for your image.  The simpler and more meaningful the better as you might revisit the image a day, a month, or a year in the future and will want to know quickly what each layer does. To rename a layer just double click on the current layer name and an editable text box will pop up.  If you happen to click in the wrong spot and the Layer Styles dialog opens, no worries.  Just close it and try again.

Layers with meaningul names but still cluttered.

2) Use groups!  Groups are like parent folders on your hard drive.  A parent folder may contain dozens of files.  When you want to see them all you expand the folder, when you don't collapse.  A group works the exact same way.)  When the layers start piling up see if there is a way to group them together.  For example, if you have five layers to optimize the sky put them into a group.  To create a group, highlight the layer or layers you want together and then position your mouse over any of the layer thumbnails.  Click, hold, and drag to the Group icon at the bottom of the Layers panel.  The group icon is the one that looks like a small folder.  It is the third from the right directly next to the create new layer icon.  Once you have a group remember to give it a meaningful name.  You can easily expand or collapse the group by clicking on the small triangle to the left of the group thumbnail (a folder icon.)

With properly named groups it is much more logical and organized.

You can have as many groups as you need or want.  Once you have a group you can also add  a layer mask to selectively reveal or conceal the effects of the entire group.

Try these two techniques and see if they help manage the possible confusion and clutter that comes with a multi layered document.

Fiat Lux!

Hal Schmitt is Coming to Las Vegas!

Hal is bringing his new seminar The Dynamic Duo: Lightroom 3 & Photoshop CS5 to Nevada!

In this one day event Hal will demonstrate the tips, tricks, and techniques of Lightroom revealing a streamlined but effective process to execute all stages of the digital workflow from import to output. Transitioning seamlessly from Lightroom to Photoshop (via the built-in functionality) Hal will demonstrate the beauty and power of the world’s finest image optimization software.

The course will be held at:

Morgan Stanley Smith Barney
701 North Green Valley Parkwa
Henderson, NV 89074
Admission is $50 at the door, but pre-register before March 11th and pay only $39! For more details call the office at 805-528-7385 or go online to LIGHTWorkshops.com

Fiat Lux!