Physical camera advantages?

[archkre]

Can anybody explain what is the advantage of using Physical camera

over regular Max camera?

And how do we use that Phy-cam related to Vraysun, etc?

Can you give a numerical example, please?

Let's say for an exterior render with Vraysun to multip.=1: what values would you give to the Phys. camera?

And can you explain in simple words what "linear space working flow" is ?

Thanks

[Ricardo Eloy]

In a nutshell, the new VRayPhysicalCam is a way to simulate a real camera. So, if you intend to use it, you gotta know exactly how a real cam works. It allows you to use real world values for lightning, which is really cool.

To find out about LWF, try the search engine on the top of the page. It has been discussed several times around here.

[Sawyer]

To really grock the physical camera you need physical camera experiance. There are limitations that a real camera gives you that you don't have in a 3d enviroment. A max camera was really just a place holder for a view. A physical camera recreates most of the limitations inherent with a real camera. One of the major features a real camera has is a light meter that is very different from how the eye sees (and the way the brain interprets information).

One of the trickiest things to photograph is an exterior in full light and keep the detail in the dark shadows. This is because the sun is a really huge value, interior lighting is exponentially lower level lighting. In the past we have been lighting buildings using simular values for an exterior sun and interior lighting. Now with a p.c. you have a film stock that is callibrated for a real world sun so you have to use real world units to record it. Now the sun is 100x times brighter than a "light". That is the way it really is and requires lots of tricks to compensate for certain situations.

Another really difficult situation is an interior lit by the sun - same thing the sun is so bright the shadows inside the house are so dark the camera will not record both extremes. In real photo shoots interiors are lit by really bright flash lights to bring up the shadows. So you may need to rethink your lighting setup to use a real camera.

 

Anyway I would not change the sun mult. from 1. Instead use film speed, fstop and shutter time. Using those is a pretty large topic. But of course there are great resources on the web.

 

http://www.robert-barrett.com/photo/exposure_calculator.html

 

LWF is a method to compensate the way the monitor incorrectly handles colors. Your monitor does not have a good gradation of grey working with LWF corrects teh incorrect grey scale.