Helicon Focus is an application that allows you to create a completely focused image from several partially focused images by combining the areas in focus. Its main use is for macro photography and microscopic photography, but it does wonders to beat the diffraction problem on landscape photography as well.
Helicon Focus is developed by HeliconSoft, a small Ukranian company. Except for Helicon Focus, HeliconSoft also develops Helicon Remote, a utility that automates focus and exposure bracketing. The program sends commands to camera via USB to change focus distance in regular intervals. Finally, the Helicon Filter image editor and a couple of freeware apps round up the firm’s portfolio.
I was given the opportunity to test Helicon Focus. Helicon Focus offers:
- advanced interpolation techniques
- a 16-bit workflow
- Camera RAW support
- an unlimited number of images
- resolution capabilities of over 100 Megapixels
- 64 bit support
- a Windows and a Mac version
It is very fast on an iMac i5/3.1GHz with 12 MB of RAM. The app is multi-threaded, i7 compatible, and you can work in batch mode. Command line mode is also available. Except for two different rendering methods, the program also has tools for cleaning up the final image, including a brush to to pick up sharp areas from individual photos, a 3D model of the depth map, a dust map, the ability to create a limited 2D panorama, and support for Helicon Remote if your camera is on the supported cameras list (and Sony — as always with its proprietary, non-standard remote functionality — is not on it).
We were given the Pro x64 version to play with. This is the multithreaded, multiprocessor capable version. It’s the fastest and it includes all of the features mentioned above.
Shooting for depth of field
The actual multi-focal workflow starts before you have touched Helicon Focus. You first need to take a number of shots, each with a different focal point. The only way you’re going to get images that are usable by Helicon Focus, is by using a tripod.
In macro photography as in landscape photography you can’t get a depth of field that is infinite. The largest depth of field is obtained by closing the lens (using a large f-stop) to its fullest. In theory, this should result in sharp focus across the entire image and depth of the scene. In practice, a phenomenon known as diffraction causes some areas to be out of focus.
This is true no matter what type (or price of) lens you’re using. What Helicon Focus proposes is to take a relatively large number of photos with your camera set to manual focus. You take each photo with a different focal point. Best is to start with one end of the focal range of your lens and then work your way through small focal changes until you reach the other end. For example, for landscape photography — which I tested Helicon Focus with — you can start setting your lens at 0.35 meters (on my lens the closest that I can get) and increase the focal length in small steps all the way through Infinity.
Once you have all these images, you can offload them to your Mac and import them in Helicon Focus.
Workflow to get dramatic sharpness
The first thing you’ll notice when starting Helicon Focus is its large empty working space. You populate the working space with photos by clicking on the Add Images button, and selecting any number of images to import. I used my Alpha 700’s RAW images.
You can quickly browse through all the images to check whether every one of them has some area — however small it may be — in focus. Images that have no area in focus at all, e.g. because you stood too close by, can be turned off in the app.
As soon as you’re happy with the images that are selected, you render the ‘scene’. What you end up with is a combination of the sharp areas of the selected images. An algorithm is applied that either computes the weight of each pixel based on its contrast, or that finds the source image where the sharpest pixel is located, creating a ‘depth map’ from that information. The depth map can be loaded in one of HeliconSoft’s free programs, Helicon 3D Viewer.
The end-result is an image that has infinite depth of field — sharp from close by to far off. However, I noticed that the success of the program depends in large part on the quality and number of steps you took when shooting. In my studio I saw that with some lenses you need to take smaller focus steps the closer you get to Infinity in order to have all the objects the farthest away in focus.
When you get that right, the results you can achieve with Helicon Focus can be amazing, with every detail as sharp as a razor blade (well, depending on the quality of your lens, obviously). Additionally, you can experiment with the program’s algorithm settings (2 sliders) to achieve the best result.
As Helicon Focus was originally developed to help macro photographers get their tiny subjects sharp overall, the program does add artefacts in some circumstances. For example, when shooting a scene against a bright backdrop, the objects closest to the light source (in my case, a window) get a halo effect.
That looks disappointing at first, but Helicon Focus has retouching tools, and the one you’ll use the most will easily and quickly get rid of those ugly halos: the Brush tool lets you pick an image with the halo infested objects in sharp focus and ‘paint’ the part of that image into the rendered result. Obviously, the brush also serves to get rid of small artefacts that can show up in the rendered image.
If you had dust on your lens or sensor before you started your photo shoot, each speckle of dust will become more visible in the rendered end-result. To get rid of dust, you can shoot a dust map — it’s explained in the Help — and apply that to the rendered result, and gone is the dust.
Finally, Helicon Focus enables you to create a micro panorama. This feature is intended to stitch images made through a microscope, so it’s not a full-blown panorama functionality. I didn’t test it, but it should work fine for the usage it’s intended for.
Exporting the rendered image is a no-brainer. You can export to Photoshop, TIFF, JPEG, JPEG 2000, PNG, etc. The import capabilities offer the same sort of flexibility.
After having used Helicon Focus for about a week, I find the program to be addictive once you’ve started to create a “Helicon Focus image” you want to create another one, and another one…
Despite its ease of use and simple interface, Helicon Focus is a very powerful application. Much of the power remains unseen under the hood, but it’s there, and it can result in stunning images.
Helicon Focus is addictive because it challenges not only your technical skills — to set up your camera in the most optimal way, to change focus with tiny steps, to master your equipment — but also your creativity. The overall sharpness Helicon Focus is capable of generating, opens up novel usage patterns of a dSLR for landscape and architectural photography.
And if you should get bored with the landscape or architectural or similar uses for the program, there still is macro photography for which it ultimately was intended to start with.
The Pro x64 version of Helicon Focus costs approx. €220.00.