Camera aperture parameters: Any clue what they are good for?
When I recently played around with the camera settings for depth of field, I came across three camera parameters that I never touched so far:
- Aperture Ratio (default = 1.0)
- Aperture Blades (default = 0)
- Aperture Blades Rotation (default = 0)
The Poser manual does not even mention these parameters (duh!) and even Google seems to fail.
What are these parameters for and how do they influence my render?
Aperture blades relates (I think) to the bokeh effect in photography; you'd need a background with a number of small bright highlights to test it.
@Oldenburg Well, I did google it and Aperture ratio is the lens or shutter speed of the camera. This is also referred to as the F-stop. Basically, it's how fast... or slow, the aperture blades open or close.
The aperture blades then are the thin metal blades that open and close to let light through the aperture. And Caisson's right about the bokeh effect. The number of blades determines how circular that light will in that effect. The more blades, the more circular. 5 blades or less will give you a square looking bokeh effect. Most high end cameras tend to have between 7 and 9. And you can get them even higher.
Here's two articles that may help you understand better.
@eclark1849 F-Stop is how wide the aperture is and does have an effect on DOF, generally the lower the number the greater the effect and the less depth that is crisp.
All these parameters are here for bokeh effect.
Ratio = power of the effect. @eclark1849 F-stop is the different parameter in Poser.
Blades = how many edges will bokeh have. 10 and more = circular bokeh. 7-9 most realistic, but for the kicks, you can go as low as three.
5 blades example
Rotation = rotate bokeh from the default position, so you can align it according to your plan. Meaningful only for low blades number. So I could make pentagons tips look exactly to the top, or slightly rotate it, as I had done.
You have DoF activated in the render settings for these parameters come to play.
So it's all about the bokeh. Thanks a lot for pointing that out!
I wonder why this isn't mentioned at all in the manual...
Ratio = power of the effect.
Nope. Ratio refers to the aspect ratio of the simulated anamorphic lens. An anamorphic lens is used to change the image aspect ratio projected onto the sensor, allowing a fixed size real-world film (such as 35mm) to take on various cinema-desired wide screen formats that don't actually fit the film. (E.g. go look up "cinemascope", https://en.wikipedia.org/wiki/CinemaScope)
When an anamorphic lens is used, the bokeh circles become ellipses. This was never the intention of anamorphic lenses - it's a side effect that we all now just expect to see. Simulating the effect reinforces the "photorealism" of a render, particularly when you're rendering a movie.
You can read lots more about this here: