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View Full Version : A question of perspective ? LW/MAX



F1Racer
06-03-2006, 02:39 PM
Hi

Im part of a team that makes F1 season car mods for games and I make the renders of the cars that are made.
Up until now ZModeler was used to create the cars, this season the modelling guys are using MAX7.
Of course I render in LW so I convert the car when they are finished making it.
The problem Im seeing is that when I render the car it looks kinda long an stretched. We are banging out heads trying to work out why this is. I keep the camera settings I ususally use (40mm focal length).

When placed against a side photo of the real car, the measurements are pretty much dead on.

Anyway my colleague rendered the car in MAX and I did one in LW and there is a difference in the result if you view one after the other (such as with ACDSee) or layering them in PS and sliding between them.

What Im wondering is, is this a quirk of LW ? The MAX render seems more accurate somehow.

Ive enclosed the pics to demonstrate. Anyone any idea why this occurs ?

The shot with the wheels on make the car look like a stretch limo :)
I think the front wheels are a bit too far forward so this may exaggerate this effect though.

Pic1 (blue bg): LW render
Pic2 (yellow bg): MAX render
Pic3 : LW testrender

toby
06-03-2006, 04:09 PM
Is your Aspect Ratio the same in both cameras?

Also, the Apeture Height can effect the zoom that your 40mm gets you in LW.

We have transfered cameras from Max to LW where I work, so I know there is a way. But it was done by someone who understands cameras better than I do -

F1Racer
06-03-2006, 05:54 PM
Hi toby,

Yeah aspect ratio was the same in both at 1.333 (800x600)

Both of these sideview shots were done at 36mm focal length (Max's default I believe).

toby
06-03-2006, 06:51 PM
I'm actually refering to the Pixel aspect ratio, which should be 1.0 unless you're rendering for television. It's right under the width and height fields in LW's camera properties. Any other setting will stretch the image.

Try to find the aperture height in Max and match it in LW - if you change this in LW, you'll notice that your Lens Focal Length value will change. So if you can match the aperture, then put the Lens at 40mm, it might do it.

F1Racer
06-04-2006, 03:16 AM
The pixel ratio is indeed 1.0.

I will get my colleague to have a look for the aperture height in Max.
Thanks