v1.45 v1.46 Frischluft Lenscare OFX

Depth of Field: Depth of field effects (dof) happen in all real optical devices to a certain extent. It is heavily used in photography and film as a style element. In computer graphics dof is usually generated using ray tracing techniques which increase rendering times considerably. With Lenscare plugin depth of field effects can be generated fast as a post process. It uses a depth buffer for its calculations.

Out of Focus: ‘Out of Focus’ is a fast Version that creates a blur with constant radius over the complete image. It is a good complement to ‘Depth of Field’ and offers some extra functionality. It is possible to use a custom drawn lens in addition to the generate able ones. ‘Out of Focus’ also offers background distortion for semi transparent areas.

General: A cameras blur looks substantially different from what common blur filters look like. Lenscare offers some features to help adding realism:

Lens Aperture: A cameras lens aperture greatly defines the look its blur. Therefore they offer the possibility to alter the lens apertures form to simulate several kinds of real cameras. This is important if you want to comp cg elements into real footage or just want your cg shot to fit in with the rest. A wide range of apertures can be simulated. The Out of Focus plugin provides the possibility to completely replace the aperture with a custom image. The aperture’s form is most apparent in a picture’s highlights.

Highlights: In reality very bright image parts are predominant when being out off focus. Unfortunately common graphic formats cut of bright parts. Therefore Lenscare plugins offer the possibility to select parts that are supposed to be brighter and give those parts a brightness boost.

Background distortion: Only available in ‘Out of Focus’. When looking through a blurred object the background is distorted due to the blurred object in the foreground. Most of the time this effect is not very apparent. But slight distortions help adding to the believability of your comp. To experience this effect try holding your finger in front of your eye so that it is out of focus. Now look through the blurred region on whatever is behind. Move your finger around slightly to see the effect better.

Advantages over other solutions: Apart from its speed and quality, an important advantage of a depth of field post filter is that you are able to test various focus settings easily without re-rendering the whole scene. That way you can quickly get an impression what settings work out best for your shots.

Speed: ‘Out of Focus’ effects is a speedy 2d blur and can compete with any existing solution. ‘Depth of Field’ is very fast for what it does. In a lot of situations you can save hours of render time for just a couple of seconds per frame in post processing. This is a big advantage especially with high quality global illuminated renders. Imagine what you can save on animations.

Issues: There are common unavoidable problems that all post processing depth of field solutions have. It’s not possible to blur reflections or objects behind transparent objects. This is obvious when you see that the depth buffer can only hold one value per pixel. But the biggest problem is with no doubt the missing information. Depth of Field tries to compensate for missing information but of course there are situations when this is not enough. An example to illustrate the problem is a fence in front of the camera that is so much out of focus that it’s hardly noticeable in the resulting image. Now our plugin would have to make up what’s behind that fence completely. Obviously this is not possible. In such situations we advise to render in layers and apply several blurs.

Quality: Plenty depth of field and out of focus solutions are available. Unfortunately for us most don’t simulate camera effects properly. Most depth of field solutions don’t do their names justice because their algorithms are not physically based. They are just methods that look nice in some situations but fail in others. A common mistake for ‘depth of field’ filters is to ‘blur’ all the surrounding pixels without regards to their depth values. Usually this results in ugly glow effects in regions with great differences in depth.

Stochastic or super sampled ray traced blurs suffer from artifacts if not enough samples are used. Frischluft filters don’t have these problems, and do not produce any such artifacts. Both filters support 16bit image format.