645 PRO’s Photo Filters

Jag.gr’s iPhone photography app 645 PRO comes with a feature called Photo Filters. These emulate, in software, the effect you get from putting a glass filter in front of a camera’s lens. Photographers have been using glass (and gelatin-based) filters for years, as a way of modifying the quality of the light that hits the film in their camera.

The rise of digital photography has seen there use wane to a degree—although some, such as circular polarizers and neutral density or ND filters remain popular—as sophisticated editing software such as Adobe Photoshop CS6 makes is comparatively easy to recreate a filter effect after the image has been taken. With 645 PRO you get the option to do just that “in-camera”.

With 645 PRO Release 2.0 Photo Filters are toggled on and off by swiping left and right on the camera’s Viewfinder. Swipe up and down on the left-hand side of the Viewfinder to switch between different filters, and on the right-hand side to adjust the filter intensity from 0% to 100%.

While you can use any filter at any time—whether you’re shooting color or B&W, some filters are really designed for 645 PRO’s color Film Modes, while others are conventionally aimed at the B&W Film Modes.

Color Photo Filters

Four of the Photo Filters are specifically designed for use with color photography:

  • Warm #85 filter
  • Warm #81 filter
  • Cool #80 filter
  • Cool #82 filter

These four filters are designed to modify the color temperature of the scene, also known as the white balance. Each pack of color film is configured for specific color temperature (most commonly the relative warmth of tungsten lighting or the cool of a generic “daylight” setting). But digital cameras including iPhone can adjust the white balance as the color temperature of the scene itself changes. So why are these filters needed in 2012, the era of Auto White Balance AWB?

Well, while recent iPhones’ white balance correction is pretty good (although that of iPhone 3GS and iPhone 4 less so), it’s not always perfect. These filters allow you to correct the image to get the color temperature of the image to match what you’re seeing. Equally, iPhone’s white balance may be technically correct, but artistic considerations cause you to want the scene to be cooler or warmer. Again, these filters come into play.

For a natural effect, you should generally use these filters at a level of 25% and under; push them beyond that for special artistic effects.

B&W Photo Filters

Five of 645 PRO’s Photo Filters are particularly aimed at photographers shooting B&W. These are:

  • Red filter
  • Green filter
  • Blue filter
  • Yellow filter
  • Orange filter

These are designed to alter the color balance of the monochrome image. It’s easy to think of color as not being a key element of a B&W photograph, but the differing balance of red, green and blue light that is combined to make the various shades of gray that make up the picture can change its character quite dramatically.

Different films have different color balances (something that is reflected in 645 PRO’s B&W Film Modes) and the use of colored filters can be used to customize this further on a shot-by-shot basis. By changing the color balance, they can make different colors in the original scene appear darker or lighter in the photograph. Here’s how to use them:

Red filter

The Red filter can produce a very dramatic effect, especially with its level above 50% (for some, the effect is too dramatic). There will generally be a sense of greatly increased contrast, blue skies will get very dark—almost black in some cases. Where similar levels of red and green are side by side—such a red poppies in a green field—a red filter can make the two colors stand out against each other when an unfiltered shot would have them both appear as a similar shade of gray.

Green filter

The Green filter really comes into its own when shooting plants, as it can “lift” flowers and other differently-colored elements from the green foliage. It should be used with care, however, as it can also have a tendency to bleach out skies, so it’s best used—especially at the higher levels—with tight shots rather than big landscape vistas.

Blue filter

The Blue filter mimics the effect of early 20th Century orthochromatic film (which was only sensitive to blue and blue-green light, unlike later panchromatic films). This has the effect of darkening many colors while making skies look uniformly overcast. It’s a look that many photographers avoid but, used carefully, it can create interesting—even dreamlike—moods in the right shots.

Yellow filter

The Yellow filter generally delivers a subtle effect—so subtle that many film B&W specialists shot everything with a medium yellow filter on their lens. It’s at its most useful when shooting portraits, as the shift in color balance can help many skin tones appear warmer and more natural than they do in unfiltered monochrome—try a setting of about 20% to start with. The Yellow filter can also help separate different shades of green, so is another useful tool when shooting foliage, especial at higher levels.

Orange filter

The Orange filter sits—unsurprisingly—between the Yellow and Red filters in the effects it delivers. It can help smooth out some uneven skin tones, making it a favorite for portraits, especially if the subject has freckles! It can also, especially at the higher levels, be used to add some punch to skies that may be a bit pale. Finally, it can help to enhance bricks and stonework when shooting buildings.

Universal Photo Filters

The final two filters are for use equally with color or B&W. They are:

  • Neutral grad #1
  • Neutral grad #2

While these do not exactly emulate the use of glass graduated neutral-density (ND) filters—you just can’t do that in software, unfortunately—they do serve a similar purpose. Neutral grad #1 has a “soft” gradation, with its effect moving evenly from the top* of the image to its mid-point; Neutral grad #2 has a “hard” gradation, with a more clearly defined line between the filtered top half of the image and the unfiltered lower half.

Both have the effect of increasing the contrast of the filtered area, making them ideal for adding life to landscapes which might otherwise have skies that seem too pale. The “hard” gradation is ideal for situations where the visible horizon is a crisp line, such as the sea; the “soft” is better when the horizon is broken by objects such as trees and buildings.


With Neutral grad #1 @ 100%

Filters are fun

You can have a lot of fun—and create better photographs—using 645 PRO’s Photo Filters. But do remember that it’s possible—easy, even—to over-use them. Unless you’re after special effects (and there’s nothing wrong with that!) the best filters are often the ones that only you knew you used!

* Enhancements to the Neutral grad filters are coming in later updates to 645 PRO. In development are the rotation of the filter to reflect iPhone’s orientation (allowing for its use in portrait-format shots), as well as greater intensity at 100% (allowing for more usable variations at lower levels).