Web Sharpening

Hey Guys and Gals, I have been busily nerding out on a new web sharpening action for landscape imagery. (Not to say you couldn't use it on cat pictures, just that it is untested- and there is a small chance it would rip a hole in the spacetime continuum....)

What do you need to use this action? A semi-modern version of photoshop and a reckless sense of adventure should do. 

So what is it, and why is it better than what you are using now? 

First off, I didn't say it was better! It's just different. It is free, and the more tools in your toolbox- always a good thing, right? Long story short, I am very into editing, but not the repetitive, boring stuff like dust spot removal. With all the sharpeners i found online, getting rid of pesky halos around ridge lines, tree branches, etc is both necessary and very dull work. I wanted a "fire and forget" type sharpener, that could handle whatever I threw at it and still come back with natural results. 

Comparison of different modes at 100%. On the right, notice the prominent halos around every ridge. Next block to the left, halos are almost eliminated, but the image is still very sharp. Left of that, the haloing is gone, and the image is much sharper than the unsharpened image. Here is the image file if you want to view 100% on your own device, the web resizes these things sometimes. 

Comparison of different modes at 100%. On the right, notice the prominent halos around every ridge. Next block to the left, halos are almost eliminated, but the image is still very sharp. Left of that, the haloing is gone, and the image is much sharper than the unsharpened image. Here is the image file if you want to view 100% on your own device, the web resizes these things sometimes. 

Above is the halo mask that was generated. You can see it identified the ridge lines quite well. It works in concert with the luminosity mask and the spectrals mask. 

Above is the halo mask that was generated. You can see it identified the ridge lines quite well. It works in concert with the luminosity mask and the spectrals mask. 

 

In a very general overview, this action sharpens your image, and then hunts down and zaps any areas where haloing or over sharpening occur. If you thirst for more technical details, keep reading- if that's enough for you skip to the next section. Specifically, first it sharpens your image based on the popular method that I believe was invented by Alex Nail, and is also used in the popular TK actions. It involves resizing your image in different steps and sharpening at each point. It also resizes a completely unsharpened version of your source. Next, it runs analysis to determine areas with strong micro contrast. Then, it generates a mask to reduce or eliminate the sharpening in those areas. It outputs the result of the masked sharpened layer combined with the unsharp layer, then it runs the whole analysis/output process two more times to make sure all those pesky halos are zapped. The final, 3x analyzed mask is applied to the fully sharp layer. Next, the image is analyzed again on a broad scale to determine areas of overall lightness and darkness, and a sharpened layer free from the halo masking effect is allowed to bleed into the original image at 50%, to allow spectral highlights to appear in the darker areas of the image. (think water glinting on dark rocks in the foreground, stuff like that) Finally, a shadows luminosity mask is created, and applied to both of the previous layers, which are now in a group. Phew! 

It has 3 output resolutions- 1080 (instagram), 2048 (Facebook) and finally Retina, for high DPI displays. If you like it and you find it lacking in a certain resolution, message me and I'll see if I can add it for you. It also has 4 flavors- Strong, Mid, Light, and Natural. Natural uses full strength luminosity masking and no spectral highlights added for the most halo-free viewing experience. Strong has NO luminosity masking and full strength spectrals, for the most apparent sharpness. The other two fall in-between the Strong and Natural settings. Enjoy, and feel free to let me know what you think! 

Bright Sharpening V1

Thanks, 

Zach 

 

A few field notes on DOF stacking, and a free calculator thingy. Yay!

Perhaps you're familiar with a technique called focus stacking, or Depth of Field (DOF) blending- a multiple exposure technique where a series of images are taken with different focal points. This is done to create a final image with more in focus than a single shot would allow. The first use of this technique was in the sciences, for documentary shots of very small objects such as insects or microscopy. It has since become popular with macro art photographers, and as of late it's been popping up in landscape photography. 

With macro subjects of flowers and insects, depth of field is incredibly thin- even with small apertures. The benefits of focus stacking are pretty obvious for this sort of photography. Yet, with a wide angle lens, DOF is already quite large. So why would you want to use a complicated technique, when you can just back up a little and get everything sharp? The main reason is compositional flexibility. Sometimes in a technical art such as photography, your equipment can limit your creativity. DOF stacking can allow you more freedom. If you use a wide lens, you already know that position is absolutely critical to composition. Using DOF stacking and a 14-24 mm, I can get within inches of a mossy rock, stream, or icy pool, turning tiny details into leading lines or eye catching, interesting shapes.  If I get close enough, the entire bottom third of a vertical shot will be a patch of ground about the size of a magazine, with the background still able to include a good size mountain range! This allows an enormous amount of compositional variation. If you haven't tried it, give it a whirl. What's the worst that could happen? :) 

The basic method I use is as follows- first, I find my composition with a combination of either looking through viewfinder/live view or test shots. Next, I set up my tripod to accommodate the comp. (Don't be tempted to do the reverse- setting up a tripod and then looking for comps will make you miss a lot of great options with a wide lens!) By the time I find what I'm looking for, my tripod is often fully collapsed and my lens is quite close to the ground. Even a movement of a few inches completely changes the composition. I look for strong leading lines, repeating patterns, and subjects that will complement my background subject. Once I'm happy with everything, I take the series of shots. (Manual focus) The first shot is always focused to infinity. Next, I focus a bit closer, while leaving enough overlap of sharp areas to allow easy blending. I repeat this until every part of the composition is in focus for at least one exposure. I find that I can cover the entire possible focal range of the 14-24 2.8 Nikkor lens (at 14mm/f16) using 5 shots. Some pros use only 3 shots, but I'm not quite that confident in my manual focusing yet! :) Note that many lenses zoom out a bit as they focus closer, so allow a little wiggle room in your composition for cropping later. And finally, be aware that a flat subject such as rock or ice will lend itself to much easier blending than a bunch of flowers blowing in the wind- for reasons of both motion, and the added complexity of blending subjects that are separated from the background by a large distance. 

Once the images are in the computer, I make any RAW adjustments to all files simultaneously. I then stack all the images on top of each other in Photoshop. I use either auto or manual alignment to line everything up. The final step is hand blending with masks. (Personally, I haven't had much luck with the auto blend in Photoshop, or any other automated focus stacking software.) Manually blending the images can be quite easy and quick, or incredibly painful and slow- it mostly depends on your subject matter and proficiency with masks. A hard edged brush with 100% opacity is a good start. Take your time and check everything twice, it's easy to miss spots. 

DOF blend to capture reflection in a very small pool of water. Nelsons Ledges, Ohio. 

DOF blend to capture reflection in a very small pool of water. Nelsons Ledges, Ohio. 

When I started using DOF blending in my own photography, there was a lot of hit-or-miss experimentation. Every DOF stacking calculator was  for macro stuff and rather useless for wide angles. Having a bit of free time one day, I made an Excel calc that allowed me to put in desired aperture/focal length, and get a suggested set of images to take. Keep in mind that wide angle DOF stacking does not require the use of this, or any other calculator. Getting out there and learning how your particular lens  works in various situations is the best method for mastery. Still, if you'd like a general set of guidelines to use starting out, want to test out specialized nighttime configurations, or just want to see what 5 shots at 600mm/f11 will getcha- I hope you find it helpful.


DOF Calc V1


Some useful links- 


Alex Noriega

Master of DOF blending and dark overlord of editing in general, offers advanced online workshops that are in depth and incredibly helpful. Also kind of sassy, which I appreciate. 


Ryan Dyar

Another guy with painfully good photo skills, has a series of editing videos that cover DOF blending and a ton of other stuff.


Marc Adamus

As stated above, there is no substitute for learning in the field. Marc doesn't have any online vids, tutorials, blogs, or facebooks- but the tours he offers are unlike any others. I went and it was definitely one of the best things I have done for my photography. 


And final disclaimer- nope, none of these guys gave me any money. I recommend them because I've personally benefitted from their knowledge, that is all. :) 




The space between the ice on the left and right of the foreground is about 10 inches. The waterfall in the upper frame is at least 70 ft tall!

Unedited overview of the area from the first shot. This is from "standard" tripod height IE eye level. The foreground from this height didn't do much for me, but getting close allowed 3 or 4 interesting perspectives to choose from.