By Ian Lyons

A Computer Darkroom Review

PhotoKit SHARPENER is the brainchild of the Pixel Genius team (Jeff Schewe, Bruce Fraser, Andrew Rodney, Martin Evening, Seth Resnick and Mike Skurski). The following review should prove enlightening to even those who think they know all about sharpening digital images.


1. Introduction

As photographers we tend to under-sharpen our images, which invariably results in soft-looking prints lacking in fine detail. On the other hand our friends (okay I'm stretching the friendly part) in the prepress industry go the opposite direction and tend to over-sharpen; creating crunchy images that are effectively impossible to re-purpose. So what is it with sharpening digital images that causes both camps to get it so wrong?

Sharpening is one of those necessary evils that digital imaging seems to impose upon us. There are several, sometimes contradictory reasons for this, but basically they fall broadly into two areas of the digital workflow.

1. Capture

The process of capturing the image using a scanner or digital camera will result in some softening of fine detail. Film grain, imperfect optics, and the method of interpolating the missing colour data from one-shot digital captures are only but a few examples for image softening. This softening can't be avoided and in some cases may well be a deliberate ploy on the part of the hardware vendor. To overcome this we often find the scanner or camera software will include sharpening features. Alas, these tend to do more harm that good resulting in visual artefacts that get worse rather than better as we begin the process of editing the image.

2. Output

As with the capture process output devices will introduce some softness. Remember, we're turning pixels into dots of ink or dye will introduce further softness. Each output process or media will have its own limit on how much detail can be reproduced and so a fixed formula will likely result in poorly optimised prints.

In effect, we need to apply sharpening to overcome each of the problems identified above. No problem you say, simply apply the appropriate amount of Unsharp Mask (USM) in Adobe Photoshop and all will be well. Not so, because what's good for one type of capture is often very bad for another. Likewise the amount of sharpening required for an inkjet printer will be very different from that required for an offset press.

Unfortunately, the USM filter lacks the level of subtlety required by many images and can often result in over-sharpening. When applied globally it will help some areas and destroy others. Obviously there are also many other sharpening techniques designed for localised sharpening and each of them will have its niche. However, finding, understanding, and finally optimising them to the particular needs of our capture and output devices is easier said than done. Wouldn't it be great if we could have them all bundled together as a single solution? Well PhotoKit SHARPENER is that solution.

With PhotoKit SHARPENER we have developed a highly optimised Adobe Photoshop Automation Plug-in that provides for a 3-step sharpening workflow. The workflow is simple in concept and splits sharpening down into three easy to apply stages: Capture Sharpening, Creative Sharpening, and Output Sharpening.

The advantages of PhotoKit SHARPENER include: non-destructive sharpening with all effects being applied as Layers or Layer Sets, default settings are designed with automation in mind thus minimising the risk of user mistakes or oversight. Control is also provided via the Opacity slider and allows the user to increase or decrease the amount of sharpening at any time after the effect filter has been run.

2. PhotoKit SHARPENER Basics and Workflow

PhotoKit SHARPENER is compatible with Photoshop CS and higher and. It will not work with Photoshop Elements or any other third party image editing application. Furthermore, and as explained above the PhotoKit effects are applied as layers, leaving the original image untouched. Since Photoshop CS and higher fully support 16-bit layers and blending modes there is no need to convert 16-bit images down to 8-bit, which wasn't always the case.

PhotoKit SHARPENER comprises three menu options which are called from the Photoshop File>Automate menu (see figure 1).

Figure 1

3. Capture Sharpeners

Once the user has satisfactorily completed the larger initial colour and tone edits it's time to apply the first round of sharpening. Capture Sharpening is designed to apply gentle sharpening early on in the workflow and concentrates primarily in the mid-tones of the image.

PhotoKit Sharpener has a broad range of Capture Sharpener options covering both film and digital type capture devices. The film sets are resolution independent but it's still important to choose the correct film format. Likewise with the digital capture devices the correct device resolution should be selected. It's also recommended that pre-sharpening or resizing of the image before this step is avoided.

Choosing the Capture Device

Once the capture device type has been selected it only remains for you to choose from one of three sharpening effects. These effects determine to the extent to which edges are emphasised and the user manual provides ample examples of where and when each should be applied.

Since the sharpening effect layers can take the form of a single Layer or a Layer Set it's also possible to combine into multiple sharpening effects.

Viewing cumulative result of Medium and Wide Edge Capture Sharpening

4. Creative Sharpeners

The Creative Sharpeners are, by design, for localised sharpening or smoothing. There are three basic sharpening sets, two of which utilise brushes and the last a range of global sharpening effects. As with the Capture Sharpeners each of the brushes is based on wide, medium and narrow edges. The actual brush size, opacity and flow can also be adjusted to suit the specific requirements of the image. Portrait photographers will love the Smoothing Brushes. Likewise landscape photographers will probably find the "Haze Cutter" and "Depth of Field" brushes really useful.

Since the list of brushes and filters is too long to list here Ive included the following sample screenshots.

Sharpening Sets

Sharpening Brushes

Sharpening Effect Filters

If I was asked which of these special effects filters I like most then it has to be the "Super Grain" effects. With "Super Grain" we add the digital equivalent of photographic film grain whilst sharpening an image.

5. Output Sharpeners

Once you've completed editing your image, applied all the creative sharpening or smoothing effects, etc. it's time to prepare the image for your preferred output. First things first though resize your image to the "final" output size! A really cool feature of Output Sharpener is that it shows you the current size and resolution of the image in the actual units you've chosen in Photoshop (see below).

Selecting the Output Sharpener

The Output Sharpeners are divided into four different types of output device, with subsets for the various alternative print resolutions and media types. Good output sharpening is dependent upon you making the correct choice of device, resolution and media. Choosing a Contone Sharpener and then printing using matte paper on an inkjet printer will end in disappointment.

Output Sharpening Effects

Like the Capture Sharpeners, the Output Sharpeners use a Layer Set. This layer set will contain the Light and Dark Contour sharpening layers with the default opacity set to 100%. Obviously you can reduce the Layer Set opacity to suit the particular needs of the image being sharpened. The default opacity for the individual Light and Dark Contour layers is 50%, which enables you to independently increase or decrease the strength of each contour layer for even better control of the sharpening effect.

6. Conclusion

I think the biggest compliment I can pay the Pixel Genius team is not to simply say that PhotoKit SHARPENER produces finished images that look really sharp, but that they look very natural and display a level of detail that previously I've not seen in any digital print. That's not to say that I've not seen sharper prints, I have, but in one way or another they've always appeared overdone. With PhotoKit Sharpener there's no telltale signs of over-sharpening, halos or any of the other artefacts weve become accustomed to seeing.

At $99.95 PhotoKit SHARPENER is not cheap and no doubt many will baulk at the thought of spending so much on something as simple a set of sharpening actions, filters and brushes. However, to think it provides only tweaked versions of sharpening methods with which we're already familiar would be doing the folk at Pixel Genius at great disservice. PhotoKit SHARPENER and especially the concept of the sharpening workflow is vastly different to any I've seen or used before. It has changed my approach to sharpening digital images and my prints are much better for it. If you're serious about producing the best possible output from Photoshop you also owe it to yourself to at least try the demo version.

PhotoKit Sharpener can be obtained from http://www.pixelgenius.com and is supplied with a PDF format user manual that provides a detailed discussion on the sharpening workflow and methods.


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