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DrStrik9
05-15-2009, 03:23 PM
I'm doing DOF tests, and one of the items on my testing list is Digital Confusion. So far I got about half of it right, the confusion part. :-)

It seems to blur far too much, and darkens everything it blurs! Does anyone else use this Image Filter in LW 9.6? What's the secret to making it look right, or should it go the way of all useless stuff?

Thanks,
Michael

Captain Obvious
05-15-2009, 04:38 PM
When doing DOF in Lightwave, either use in-camera DOF (i.e. in the camera properties and with a perspective camera), or do it later in a compositing package with a depth pass.

RollerJesus
05-15-2009, 04:59 PM
Also, this tip came out of the speed modeling challenges and give some awesome DOF.

http://newtek.com/forums/showpost.php?p=806469&postcount=33

DrStrik9
05-15-2009, 05:05 PM
When doing DOF in Lightwave, either use in-camera DOF (i.e. in the camera properties and with a perspective camera), or do it later in a compositing package with a depth pass.

OK, maybe that's my problem. I was trying to use Digital Confusion as what it is: an Image Filter (much the same as you suggested in post-render comp?) -- I wasn't trying to REPLACE Camera-DOF with it. LOL

So I already have pretty decent DOF using Perspective Cam, AA = 5, Adaptive Sampling ON, Threshold = 0.03, Oversampling = 0.5, Photoreal MB passes = 1.

I have an animated null ("RangeNull") with the expression "vmag(extent(Camera.wpos(Time),RangeNull.wpos(Time) ))" which sets the focal distance to the distance between the camera and my RangeNull.

Frankly, a low amount of another image filter, "Depth-Of-Field Blur" (like 10% blur amount) helps smooth out the noise LW's much-improved renderer leaves in DOF areas without making in-focus areas look weird when they intersect larger DOF areas.

So I take it you say Digital Confusion is as much bunk as I find it to be so far. :-)

Thanks,
Michael

DrStrik9
05-15-2009, 05:08 PM
Also, this tip came out of the speed modeling challenges and give some awesome DOF.

http://newtek.com/forums/showpost.php?p=806469&postcount=33

That is extremely cool. Now I don't have to type in that bulky expression. :-)

Michael

Captain Obvious
05-15-2009, 08:18 PM
OK, maybe that's my problem. I was trying to use Digital Confusion as what it is: an Image Filter (much the same as you suggested in post-render comp?) -- I wasn't trying to REPLACE Camera-DOF with it. LOL
I really don't recommend mixing 2D and 3D DOF. I don't think it gives very good results. Either do it in post, or do it in camera. Don't do both.

DrStrik9
05-15-2009, 10:23 PM
Three ways to automate Focal Distance to a null:

A. USE Proximity
1. Make a null object called FocusNull. When you're done, wherever this object is placed, your camera will be in focus.
2. Camera Properties : Stereo and DOF Tab : Depth of Field = ON
3. Click on the "E" to the right of "Focal Distance." This brings up the Graph Editor.
4. Select "Modifiers" tab. Add Modifier : "Proximity."
5. Double-click on Proximity to open its interface.
6. Item = Camera (the item for which you are setting Focal Distance).
7. Target = "FocusNull"
8. Use = Target Only

B. USE an expression
1. Make a null object called FocusNull
2. In the Camera Panel, hit the little "E" beside the Focal Distance field, and paste this in the "Expression" field.

vmag(extent(Camera.wpos(Time),FocusNull.wpos(Time) ))

C. USE Relativity
1. In the Camera Panel's "E" Button, add Relativity Channeler, and by the "X:" type:

GAP(camera,t,focusnull,t)


(I learned those last two from Prem.) :-)

DrStrik9
05-15-2009, 10:25 PM
I really don't recommend mixing 2D and 3D DOF. I don't think it gives very good results. Either do it in post, or do it in camera. Don't do both.

Can you give me an example or two of post compositing apps that can do this well?

Thanks,
M

Captain Obvious
05-16-2009, 04:56 AM
Uh, all of them I guess? But you might need third party plugins.

DrStrik9
05-16-2009, 02:54 PM
Uh, thanks? I'll run right out and buy one of those you mentioned. ;-)

Captain Obvious
05-17-2009, 12:54 PM
Shake?

DrStrik9
05-17-2009, 02:15 PM
Shake?

That helps. Thanks.

monovich
05-19-2009, 10:48 AM
after effects via LensCare. Best DOF evar.

Captain Obvious
05-19-2009, 01:38 PM
after effects via LensCare. Best DOF evar.
But it means you need to comp in AE. I think I'd rather shoot myself.

DrStrik9
05-19-2009, 06:25 PM
But it means you need to comp in AE. I think I'd rather shoot myself.

LOL! I haven't spent very much time comping moving imagery in anything, but I do know and love Adobe apps (since before the first ones were even released!), so I actually LIKE After Effects. But I haven't really compared it to anything else, so ... still, I understand the temptation to shoot one's self. :-)

Regarding workflow and choice of tools, my personal theory is that most of us tend to "like" what we started with. Once a set of tools reaches that magic point of becoming an extension of your nervous system, it can become increasingly difficult to change course. -- That is unless, like me, you're a glutton for the punishment (joy) of always learning new stuff.

But I'm getting old enough now to forget and relearn everything on a regular basis, so learning new and/or different stuff doesn't bother me at all. Still, all software is "buggy until I understand it." LOL

LW 9.6 instantly became my favorite present and future learning curve.

Thanks again for helping the "forever noob." :-)

Michael

DrStrik9
05-19-2009, 06:50 PM
after effects via LensCare. Best DOF evar.

So is it smooth when the focal length is animated? That was the trouble in my experience with XDof. Any post blurring mechanism must decide how many blurs of various sizes to do in order to get the job done for the entire z buffer, and if it's too few, you get those "jumping blurs" which can ruin the glorious DOF effect that works so well in stills ...

Thanks,
Michael

joelaff
05-21-2009, 06:26 PM
Lenscare does a pretty nice job, and is reasonably fast. We use the OpenFX version of it in 64bit Fusion.

As far as where the focus goes I prefer to just animate the focal distance by hand. Why? Because when real footage is shot that is how it is done... by hand be the first assistant camera. Which means that there is always a hint of buzzing, which gets mimic nicely when you animate the focal distance. Of course we do VFX work. So everything is about looking like real shot footage...