Unsharp masking & Iran (2007) revisited.

Posted by ciaran on May 20, 2009 in Blog, Editing & Workflow | 8 comments

Back in October of 2007, myself and two other photographers from my camera club travelled to Iran for a photography trip. I was shooting for almost 3 years so was at a stage where I felt reasonably competent in my abilities to get some shots and in the end I came back with some images that have done really well for me in club competitions, national competitions and salons.

But recently, since I haven’t been shooting that much, I’ve been dabbling some more with Photoshop and primarily looking at sharpening. Not just from the point of view of sharpening an image, but also looking using the unsharp mask filter, to really boost contrast. So I thought: “Why not revisit the images from Iran?”

Primarily, the main modifications were boost in contrast, but rather than using levels or curves, I used local contrast enhancement (what I call defog). I think other people refer to this as HALO sharpening (high radius, low amount). Effectively you set the radius to be approx 130 pixels and the amount to be 10 (threshold to 0). I performed this step twice. It’s important to note that this can push high light detail over and also block shadows, so it may be necessary to brush back in certain areas. What I actually do, is in the cases where high light detail is blown as a result of this step, I select the high lights via the “select colour range” tool, invert the selection and then use this as the mask. So no manual brushing or intervention is needed

I wanted a little more contrast and warmth, so the next step was to use the “Soft Light” blend mode. Duplicating the defog layer, I set the blend mode to soft light. As well as adding contrast, this also introduces a colour shift, which for these images I didn’t mind too much. But I did pull the opacity back to 35% so the effect was more subtle.

The next step was physical sharpening of the image. For these shots I used the “octave sharpening” method detailed in the book “Skin” by Lee Varis. Basically, working on duplicate layers, with blend mode set to luminosity, you progressively sharpen the image. Starting off by sharpening 500% with a radius of 0.5 pixels and opacity set to 100%. The next layer, you increase the radius to 1, but decrease the opacity to 50%. The next layer the radius goes to 2 (doubling again) and the opacity goes to 25% (halving again). Finally, another sharpening filter is applied, with radius set to 4, but opacity set to 13%. Personally, I added this as an action so it can be applied to all images, but I all set the layers to be smart layers, so I can adjust the sharpening amounts later if required.

So far, all the edits have been completely automatic, so no brushing or manual intervention is needed. But my final step required a certain amount of manual intervention. To draw attention to the subject, I decided burn in the areas of the shot which were of less interest. To do this, I used the lassoo/marquee tool with the feathering value set to 250 pixels. I then very roughly selected the areas I wanted to darken. (TIP: Hold down ALT key so you can select areas beyond the boundary of the image). Once selected, I copied the selection to a new layer (Ctrl-J) and changed the blend mode to multiply, changing the opacity as required. This could also be done a few times, to selectively darken different areas more than others.

It has to be said, that I haven’t printed any of these off yet, but on screen I’m pretty happy with the results. Due to all the printing needed for the recent panels, my love affair with my printer is not at it’s strongest point at the moment. But over the coming weeks, I’ll definitely print one or two off and see what the results are really like.