Cinematic Depth of Field

Shot by Jim2point0

Cinematic Depth of Field, or 'Cinematic DOF' is a state of the art Depth of Field shader for Reshade and is available in the OtisFX repository. The OtisFX repository always contains the latest version.

This guide assumes you have properly set up the depth buffer in Reshade. Cinematic DOF is a depth of field shader which works with lens aspects for focusing and blur control. This might at first be confusing and this guide should help you understand what the various values mean and what to adjust to get the most out of this shader.

All settings in the Cinematic DOF shader are drag sliders, which means you can click them, hold the left-mousebutton and drag the mouse left or right to resp. decrease and increase the value. By holding shift while dragging the increase/decrease will go faster. When holding ctrl while clicking gives you the ability to type in the value you want.

Info

The screenshots below are taken with Cinematic DOF v1.2.5, released on March 28th, 2022.

Focusing

One of the most important parts of a depth of field shader is to focus on the right element in the 3D world. By default, the shader has its focusing mode set to auto-focus and mouse-driven auto-focus. This means that if you mouse the mouse over the scene, the element that's below the mouse pointer will be the element the shader will focus on. Everything in front of it and behind it will be blurred.

This works for some situations, however if you want to set up the shot and alt-tab to a tool to increase the resolution of the screen for instance, you'll lose your focus point. For those situations it's better to switch to manual focusing. To do so, simply uncheck the Use auto-focus option in the Cinematic DOF settings in the Reshade menu.

When you switch to manual focusing, the shader will focus on a certain distance away from the camera. What that distance is, is specified in the Manual-focus plane slider. To change the value, simply drag in the textbox till it has the value you want.

Distance to the camera

The element you have in-focus has a certain distance to the camera. The closer it is to the camera, so the closer the focus plane is to the camera, the stronger the blur will be in the out-of-focus areas.

Focusing overlay

Cinematic DOF has an important focus helper, its out-of-focus plane overlay. When the Show out-of-focus plane overlay on mouse down is checked, the shader will show an overlay every time the left-mousebutton is pressed and held down. The overlay consists of three colors: white for far plane (the area behind what's in focus) out of focus elements, red for near plane (the area in front of what's in focus) out of focus elements and a blue line for what's exact in focus.

It also displays the hyperfocal area without any color, right next to the blue line. This area is considered 'in focus' but transitions slowly to 'out of focus'. When auto-focus is enabled, it will display a crosshair when the left-mouse button is pressed, with the auto-focus point at the center of the crosshair.

It's recommended you use this option when setting up what to focus on.

Focal length and aperture

Cinematic DOF's focusing system is based on three elements: distance of focused element (focus plane) to the camera, the lens length (focal length) and the aperture. The distance to the camera is controllable by moving the camera closer to the subject (and with that re-focusing on the element in the 3D world you want to focus on). That leaves the focal length and the aperture.

For lens length, it in general means the longer the lens, the narrower the Field of View (FoV) and the more blur you'll get in out-of-focus areas. For aperture in general it means the lower the value, the more open the lens will be, so the more light will come into the lens/camera, and with that the more blur you'll get in out-of-focus areas. For the Cinematic DOF shader, the two parameters are basically doing the same thing, as the shader itself doesn't control the amount of light coming into the camera.

So what values should you pick? To get started, let's look at the defaults the shader comes with: 100mm for Focal length and 2.8 for aperture. If you'd use a 100mm lens on a modern camera with aperture 2.8 you'd get nice portrait shots with a nice shallow depth of field and nice background blur.

Here's the default setting in action:

100mm/2.8

100mm with 2.8 aperture

Look carefully at the blurring on the wings of the statue, and the thick blurring in the background.

If we change the lens and aperture to the values of a lens that's often sold with a modern camera, a 50mm lens with aperture 5.6, the results are a bit different:

50mm/5.6

50mm with 5.6 aperture

You can clearly see there's way less blur in the background. The focus is still on the statue, camera is still on the same distance. Also the blurring on the wings is gone, they're cleanly in focus.

Here's the same scene with a lens of 100mm and aperture of 5.6:

100mm/5.6

100mm with 5.6 aperture

And with a 50mm lens with aperture 2.8:

50mm/5.6

50mm with 2.8 aperture

There's subtle more blur than with a 5.6 aperture. You're free to choose what will give you the right blur factor. It's often only necessary to change one the two, either lens length or aperture, but not both. To get started, leave the aperture on 2.8 for now and only change the lens length to a lower value for less blur and a higher value for more blur.

Tip

Moving the camera closer to the focused element also makes the blur be more prominent (and you have to change the manual focus plane if you're using manual focusing)

Blur tweaking

After you've set up the focus, the lens length and aperture, you can now tweak the blur of the near plane (in front of what's in focus) and the far plane (what's behind what's in focus). Additionally you can change the quality of the blur and apply a post-blur smoothing factor to iron out any undersampling artifacts you might see.

Let's see what these look like. We'll use the defaults of 100mm and aperture of 2.8

Far plane blur

First we have Far plane max blur. Here you can tweak the blur strength given by the lens length + aperture + distance combination. A value of 1.0 gives the default blur for that combination. A value of 0 totally switches off bluring for the far plane. If you set the value to a high value, e.g. 3.0, you get excessive blurring as seen in the shot below.

Far plane max blur set to 3.0:

far plane blur 3.0

Far plane blur with blur set to 3.0

If we change the blur to a lower value, e.g. 0.5, we'll get the result below:

far plane blur 0.5

Far plane blur with blur set to 0.5

This might look the same as using a shorter lens, like 50mm, but that's not the case: with a 50mm lens the blur starts later, deeper into the 3D world, farther away from the focus plane. With 100mm the blur starts already on the wings of the statue. Because the blur factor is set to a lower value, the blur is very subtle.

Near plane blur

Additionally you can tweak the blur for the near plane. The near plane is blurred with a soft edge to make it realistic. The same applies to the near plane blur as for the far plane blur: setting it to 0 switches it off, setting it to a high value makes the blur extremely prominent.

Below an example shot where the focus is on the statue and far blur has been disabled, using the default near plane blur factor of 1.0.

near plane blur 1.0

Near plane blur with blur set to 1.0

Overall blur quality and smoothing factor.

The overall blur quality is by default set to 5. This is the # of rings the shader will use per pixel to produce the disc-based blur. The higher the number, the more rings and therefore the more samples it will take per pixel to blur the areas in the near and far plane. The value 5 gives overall good quality results and high performance but if you want higher quality, you can, the range goes to 12. The higher the number, the more performance the shader will take.

A high quality number is in general only needed for highlights. In normal blurred areas without bokeh highlights, you won't notice much difference between e.g. 4 or 9. However with a scene with a lot of bokeh highlights, you'll notice dots with low quality settings in highlights, if the blur factor is high enough. This is a side effect from a phenomenon that's called undersampling.

See the following scene:

Blur quality 5

Blur quality set to 5

It has the quality set to the default, 5, and a high blur factor and no undersampling mitigation. The focus is on the metal pillar in the from right. You can see some dots in the bokeh highlights in the middle-left, so the highlights are undersampled here. We can increase the blur quality to a higher value to get rid of this side effect, or check the 'Mitigate undersampling' checkbox in the Advanced section.

Blur quality 5 with undersampling mitigation enabled

Blur quality set to 5 with undersampling mitigation enabled

We can also achieve that with another option, the Post-blur smoothing factor. This setting applies a gaussian blur on the near and far plane to smooth out the highlights. It's a less subtle option than the quality setting, but the performance is better.

In the shot below the undersampling mitigation is switched off, and the smoothing factor is used to get rid of the undersampling artifacts instead.

Blur quality 5 smooth

Blur quality set to 5 with smoothing enabled

Not all artifacts are gone though: bokehs with low brightness are skipped to avoid blurring non-highlight areas. It's a trade-off and it's up to you what to use in a particular scene.

Highlight tweaking

A depth of field effect creates bokeh highlights, of which we've seen an example of in the previous section. To help the shader get proper bokeh highlights, Cinematic DOF has a variety of settings which can help you create the bokehs you want.

Busy Bokeh factor

A bokeh highlight is a typical round highlight with an even color. However you can change the round highlight to be a circle which is more transparent in the center than it is on the edges. To do this, increase the Busy bokeh factor to a value bigger than 0. The example below shows the highlights with a factor of 0.5.

Busy bokey factor 0.5

Busy bokey factor of 0.5

Highlight boost factor

There's a Highlight boost factor setting for boosting the highlights a bit.

Highlight boost factor off

Highlight boost factor of 0.0

However if we crank the Highlight boost factor to 1.0, we get a totally different scene:

Highlight gain 1.0

Highlight boost factor of 1.0

There's also a gamma factor which boosts all pixels a bit. In general you should leave it at its default value, 2.2, but it could help in dark scenes.

Anamorphism control

There are various lens effects known from cinema, one of them is anamorphic bokeh shapes, which means the bokeh shapes don't form perfect round circles around edges but ellipses. This effect is caused by using a lens to project a wider image onto a narrower lens opening, resulting in vertical ellipses. Cinematic DoF offers this feature and adds additional options to distort the ellipses to mimic edge distortion as well. These three settings are combined in the Anamorphism control section in the shader controls.

Anamorphic factor

The first factor is the factor to control the amount of the anamorphism of the bokeh shapes, the Anamorphic factor. By default it's 1.0, which means all bokeh shapes are fine round circles. Moving the value down to 0.0 will make them appear more and more like elipses. Below is an example of a scene with an anamorphic factor of 0.7. It shows slight deformation around the edges, but close to the center the shapes are still round. This can be used to mimic edge distortion in fisheye lenses.

Anamorphic factor

Anamorphic factor of 0.7

Anamorphic spread factor

The default spread factor makes the anamorphism appear to the edges, not in the center. To make it show up evenly everywhere, you can increase the Anamorphic spread factor to a value higher than 0.0, with 1.0 being the factor where the anamorphism is applied everywhere evenly. An example of that is given below.

Anamorphic spread factor

Anamorphic factor of 0.7 with spread factor of 1.0

Anamorphic alignment factor

The Anamorphic alignment factor is the factor that gives us the classic anamorphic effect of vertical ellipses: using a value of 1.0 the ellipses are aligned vertically like with a classic anamorphic lens. If you use a value lower than 1.0, the ellipses are rotated around the center, with a value of 0.0 being the alignment we've seen in the previous shots. An example of having the setting set to 1.0 to get the classic anamorphic lens behavior can be seen below.

Anamorphic spread factor

Anamorphic factor of 0.6 with spread factor of 1.0 and alignment factor of 1.0

Go wild

You can get vortex swirlies if you want:

Go wild

Anamorphic factor of 0.01 with spread factor of 1.0