Real Lens Flares

Core Projections

We pointed out earlier that core projections are the building blocks of lens flares. You’ve already seen how these projection types can exist on the projection strip and comprise the layers within a preset. Before we progress further under the hood with presets, it’s important to have a thorough understanding of each core projection type.

 

Note: The order in which core projections appear in the Real Lens Flares interface, from Light Ball to Gate Flare, roughly reflects (if you will) the progression of light from its exterior source through the lens surface and inward through the lens elements. You might think of it as an order of operations; the technicalities fall beyond the scope of this user guide. However, following that order doesn't necessarily make for the most intuitive user guide experience. Thus, we're going to explore these core projections slightly out of order, dealing with the usual flare elements on this page and the Schmutz core projection separately.

 

Light Ball

Light Ball is the odd duck in this group. It is the only core projection that only simulates a light source and not the artifacts generated within a lens by a light source. In the images below, we show both core projections on the left at 100% exposure. On the right, we turned the exposure way down. You can see how the light ball holds its shape, because there's a "real" thing there. The glow ball, on the other hand, gradually diminishes into nothing as exposure reduces.

We took a project setup from our ECP page section on Obscuration and used it to compare light ball vs. glow ball interactions in a real scene. In the following example, you can see how the glow ball (left) bleeds around those factory stacks differently than the same-sized glow ball (right). We worked to make the two effects as similar as possible, but it's clear how differently they behave when confronted with real-world physics. In fact, close analysis would reveal that the light ball, broken up by the foreground objects, creates multiple lens flares. Glow balls will not do this.

The Light Ball core projection offers a few controls in the inspector pane.

Starburst

The starburst accompanied by a lens reflection is probably the “look” most people associate with the term lens flare. However, starbursts are inherently tied to aperture. The graphic below illustrates how aperture size can reshape overall flare appearance.

Source: https://www.slrlounge.com/diffraction-aperture-and-starburst-effects

And here’s a fun fact: The number of blades in an aperture determines the number of spikes/points in the starburst. An even number of aperture blades yields the same number of spikes, but an odd number of blades will yield double the number of spikes.




Notice how, despite having the same number of points, the spikes for the aperture settings of 3 and 6 have different appearances.

This relationship between starburst and aperture is why the starburst, unlike any other core projection type, has two inspector pane sections: a starburst control set (shown below) and a detailed aperture control set (discussed in this User Guide’s lens pane section).

The starburst control set should look familiar if you read about the inspector pane’s light source group. Here, you have five attributes/features to control:

Glow Ball

As you see in the above image, the parameters in the Glow Ball control set largely match those of the Starburst control set. That leaves four new variables to explore:

Halo

You know how smearing grease, fingerprint oil, or some similar substance on a lens can create a hazy “halo” effect in lens flares? Sometimes, tiny scratches on the lens create a similar effect. VFX Real Lens Flares faithfully produces these artifacts with the halo projection.

Whereas glowballs are produced from circular seeds, halos derive from rings. And just as glowballs produce fascinating chromatic effects in their spikes, halos create beautiful rainbows in their rings.

After the usual settings found in prior projections, the halo control set has several unique options:

Ring

Specific lens and light source attributes can produce colored rings around lights. Adding a ring around your flare(s) can lend extra drama and realism to your scene, which is why it was an especially popular look in the 1970s and '80s. Due to copyright concerns, we can't directly show you one of the most brilliant examples of red ring use in modern cinema, Ridley Scott's 1982 masterpiece Blade Runner. However, if you're curious to see how Scott used red ring flares, maybe check out this educational video at 19:49. For another great example (and some ring flare discussion), see the shot from Spielberg's E.T. on Stack Exchange.

Ring flares are often subtle by nature, so Real Lens Flares defaults to values that reflect this. Keep in mind that rings may be tougher to spot in scenes with non-black backgrounds. In the following image, with that gray backdrop, we had to raise Exposure to 2.00 to make the ring detectable.

Enough subtlety. Let's crank up these settings and see what ring flares can do.

Size determines the ring's diameter, and Exposure controls the projection's brightness. At Exposure: 7, our ring is glaringly obvious, but it allows us to see the impact of other parameters.

Use Cone Angle and Feather only affects your flare when using a spot light as the source. Spot lights in AE have cone angle and feather controls, so this parameter allows you to determine how much of an effect those adjustments have on the ring.

Chroma Separation mimics the prismatic qualities of some lenses and their coatings, creating rainbow-like color bands. Conventional red ring effects show very little chroma separation. Of course, your ring doesn't have to be red, and the Colorize wheel makes it easy to fine-tune your ring to the scene's existing lighting.

Thickness adjusts the ring's width. You can think of Softness as the ring's blur, with 0% (minimum) giving clearly defined edges to color bands and 100% (maximum) yielding very natural blending from one band to the next.

Center Offset allows you to shift the ring's position relative to the flare's location in the image. In the following image pair, see how changing Center Offset from 0 (left) to 200 (the maximum, right) has a fairly inconspicuous effect.

Now, compare that to the same settings when we move the flare's source near the scene's corner.

Single Spike

The single spike, like the halo, is the sort of artifact you might witness from a lens smudge. Oils or other distortions on the lens create a linear flare that, especially when layered with a starburst or glowball, can create striking visual drama.

The single spike control set contains most of the same settings found in earlier projections, including the spike settings found in the glowball control set. The three new settings introduced with the single spike are:

Be sure to play with the possibilities of mixing spread with the chromatic effects of introducing spikiness. Compare the above default core projection to the variation on it created below.

Gate Flare

A gate flare mimics the effect of a light bleeding through an opening just off the edge of the field of view. To use the gate flare, set the light source position just outside the edge of the frame, then slowly drag to move it toward the center of the frame. In practice, this can be a bit tricky, so be careful and don’t blink.

The gate flare settings can be equally finicky. For example, in the image above, the flare is visible with a gate width of 105 percent. With no repositioning, the flare vanishes lower than 102% and higher than 109%, even though it remains visible in the projection strip thumbnail.

Maxon will be adding interface elements to help users more easily manipulate gate flares in an upcoming VFX Real Lens Flares release.

Reflections

Every lens flare preset contains a reflection on its projection strip. This may not be immediately apparent with core projections because reflections are hidden by default. VFX Real Lens Flares does this to help preserve the clarity of core projection forms when first viewed. You can see in the below capture of the Starburst – Kaleidoscope core projection preset why this might be advisable. The starburst gets a bit lost in its reflections. It’s better to work with a clean core projection first, then add in reflection effects.

© MAXON Computer - Impressum