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View Full Version : New User: XSI Default Focal Lenght

Ariel
04-07-2003, 05:52 AM
I am starting to use XSI, coming from Maya and I've noticed something quite strange. The default perspective camera in XSI has a Focal Length of 4mm, which in a standard 35mm camera would be an extreme wide angle lens. The problem is that the viewport does not show signs of perspective distortion, so i guess XSI doesn't use a 35mm camera preset. What would be the best way to set up my XSI camera so that it works like a traditional 35mm cameras?
Felipe
03-12-2005, 11:44 AM
Bumping this old thread cause I'm having the same problem now.

I have to match the camera position and lens from a Maya scene. The camera is static so I thought it won't be difficult. In Maya, camera has a focal length of 35 mm and Angle of View 54.43 degrees, which make sense to me. If I set camera focal length to 35 in XSI, the angle of view is 7.66.

Please, someone could enlight me what is going on ?

Thx in advance,

Felipe
SatoriGFX
03-12-2005, 01:17 PM
I am no expert but, if you double click on the camera in your Explorer and on the Primitive page under Format select "Slide 35 (24x36)" as your Standard you get pretty well what you are asking for. If you look on the Projection Plane tab you will see your Focal Length of 35mm (or very close, a little above that) and on the Primitive page your FOV is 53.43. Of course, you could tweak the Focal Length to make it exactly 35mm. Is that what you need?


Adam.
Felipe
03-12-2005, 01:40 PM
Thanks very much Adam.
Using the format you said I had to readjust pic and pixel ratio to match my background image (DV 720x480) and it worked out pretty well.
I would like to understand why using "NTSC DV 720x480" format I have so different values.
Saturn
03-12-2005, 01:48 PM
well Speaking about focal length without the size of film aperture mean nothing.
a 50 mm Lens on a 24x36 camera, or a 6x6 camera or in your case 35 mm camera don't give you the same angle.

You have to set correctly your Film aperture first then your lens length. Just be careful because Film aperture are in inches. For a 35mm Full aperture the size is : 0.98x0.735

You have put it on the advanced tab of camera property.
Felipe
03-12-2005, 02:26 PM
Thanks Saturn
SatoriGFX
03-12-2005, 05:17 PM
Thanks very much Adam.
Using the format you said I had to readjust pic and pixel ratio to match my background image (DV 720x480) and it worked out pretty well.
I would like to understand why using "NTSC DV 720x480" format I have so different values.

So would I. I am very confused when it comes to Camera settings in XSI (I have little experience with actual photography).

Anyhow, time to search out some good tutorials on camera setup before my brain explodes.

Adam.
Memodin
03-13-2005, 01:44 PM
Bumping this old thread cause I'm having the same problem now.

I have to match the camera position and lens from a Maya scene. The camera is static so I thought it won't be difficult. In Maya, camera has a focal length of 35 mm and Angle of View 54.43 degrees, which make sense to me. If I set camera focal length to 35 in XSI, the angle of view is 7.66.

Please, someone could enlight me what is going on ?

Thx in advance,

Felipe

I have the same problem.
From switching lightwave to XSI, objects seems to me a bit distorted because of this "angle" problem (i think). This makes me uncomfortable when working in XSI.
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03-13-2005, 01:44 PM
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