Forum: Poser - OFFICIAL


Subject: Question about P5 Depth of Field

amon_g opened this issue on Jan 15, 2003 ยท 26 posts


amon_g posted Thu, 16 January 2003 at 8:12 AM

Ok, here's an update and a possible theory...

I was able to achieve the effect I wanted, which was having the foreground and background objects out of focus while having the center object sharp. As you can see, I did it:)

The blue stick man is at the default 0,0,0 position, red is +10 (and a little positive on the X tran) and yellow is -10 (and negative on the X tran). My camera is +10 on the DollyZ and set to a focal length of 75.

In the render options I bumped the pixel samples to 7 (a 600MHz machine just really doesn't handle this stuff very well:)) and left the F-Stop at its default 2.8. Now here's where the theory comes in to play...

Last night I was always able to get the foreground object in focus, and that was by using the distance of the camera to the object I wanted to focus on, which in this case is 10 feet (using feet as the UOM, and the camera is +10 on the DollyZ, so I am assuming that is 10 feet from the subject). So I set the focal distance to 10. With that setting, DOF never really seemed to work the way I expected it.

I went to the DOF calculator, and tried using the Hyperfocal distance, which ended up being 219 feet (this was at the 35mm setting on film type). Well that didn't work either. Nothing was in focus. So I ended up doubling the focal distance - setting it to 20 - and then tried rendering again. And, like in Gold Fish, I got what I wanted.

Oh... as I was posting this message, I think I figured out the DOF Calculator.

Set your film format to 8x10. Set your focal length, in this case 75mm. Set your f-stop (2.8) and then the distance to the object (10 feet). Hit the compute button. Take a look at the Hyperfocal Distance. 21 feet and 11 inches. Now that's really close to the settings I ended up with in this render. So, I think the Hyper Focal Distance is what we're looking for for Poser's Focal Distance.

Ok, if none of this has made any sense, I'm sorry. It's still too early in the morning and I haven't had enough coffee:) I'll do some more experimenting tonight and let y'all (yes I'm from Texas:)) now the results. And, if you'd like, give it a try also and see what you come up with.

Thanks for reading my long winded post:)