Depth of field

[joaopaulotc]

Re: Depth of field

Hi
I've also been having some trouble with DOF.
I can get some kinda DOF with the physical camera, but instead of a REAL DOF I just get a blurry image...
If you set the override focal distance to a low value it means that the DOF starts closer from the camera (I think), but I still just can't make different focusing for different planes like it should be. What am I doing wrong?

One other thing...
what is Center Bias, Anisotropy, Subdivids, Sides and rotation for?????

thanks in advance

J.

[dalomar_cg]

Re: Depth of field

As far as why your stuff just comes out blurry, its an issue of setting the right focal distance. That will determine what is sharp and what isn't...unfortunately I don't know a good way to retrieve this in SU (sorry not much of an SU guy).

As far as the "other thing", I'll go with the first pair...Anisotropy and rotation...Anisotropy adds essentially a directional affect to the DOF (think of brushed metal, or a more DOF example, motion blur). Rotation is simply a means to control that direction.

Sides and Center bias are a way to control the quality of the DOF in terms of real world camera simulation. By default, DOF works of off a perfectly circular and perfectly balanced DOF model. This is not how cameras work in the real world, since there are sides to the aperture and the distribution of light is not the same from the center of the frame to the edge. All of this contributes to whats called Bokeh effects, in which the shape of the aperture become very apparent. Sides will control the number of sides (think polygon instead of circle) and center bias will change the light distribution (kinda like vignetting, but only as the DOF increases).

Lastly subdivisions is the means to control the smoothness of the DOF. Keep in mind that the smoothness will also be affected by the antialiasing, so I wouldn't fool around with this too much and leave it at the default 6.

[kc.rkitek_cg]

Re: Depth of field

Funny, dalomar...you said DOF isn't supported w/ physical camera, but I swear I see it! ??? Maybe I'm loosing my mind.

To get the focal distance in SU, download this free ruby plugin for SU:
http://www.smustard.com/script/CameraDistance
Save it to your SU Plugins directory and restart SU.

Next, select the object you want to focus on, go to the camera pull down menu, and select "Distance to Object"...As long as theres a clear line of sight, you'll get a popup that states the distance from the SU lens to that object. In the Vray render options, under Depth of Field, check "Override Focal Dist." and enter that number (in imperial units, this must be in inches. metric, i'm not sure).

Then, depending on the strength of depth I want to show, I try some variation of the following 8 settings to the physical camera. I have to make adjustments to film speed/shutter speed per your lighting and the F-stop, but it's a good start. They go in order from strongest visible depth to almost no visible depth:

F-number = 1.0 , Shutter speed = 8000
F-number = 1.4 , Shutter speed = 4000
F-number = 2.0 , Shutter speed = 2000
F-number = 2.8 , Shutter speed = 1000
F-number = 4.0 , Shutter speed = 500
F-number = 5.6 , Shutter speed = 250
F-number = 8.0 , Shutter speed = 125
F-number = 11.0 , Shutter speed = 60

can anyone else confirm they can achieve DOF w/ physical camera?

[dalomar_cg]

Re: Depth of field

Again, I'm not much of a SU guy, so I've never come close to going through the process of DOF with the physical camera in SU. I know that it wasn't working in Rhino for the longest time, but now it is. Its possible that it was always there in SU, and I assumed it wasn't working everywhere (sorry).

I guess I'll take a look at the script and see what I can find.

[thomthom]

Re: Depth of field

DOF with physical camera works here.

Though, I had some problems at first. I used the ruby to return the distance of the object. It would not give me correct distance unless I deleted the objects around it. Hiding the objects around it didn't seem to work.

Once I had the distance, in mm since I work metric I still had problems. Turns out that the V-Ray dialog requires inches and doesn't use the model units. Once I converted the metric units returned by the plugin I got it working fine.

P.S. I really wish that the VfSU manual would be properly updated. I find it confusing reading references to Rhino and older settings. Some times the wording is different in V-Ray from what the manual claims.