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Johnny
02-13-2004, 07:33 PM
I can see the focal distance ring get larger or smaller, but don't see any similar feedback about f-stop...

the manual says that a quick shader render will quickly show the results of a given setting, but what I get doesn't show anything w/respect to depth of field..IOW everything looks flat, and I can't see any difference between in-focus and out-of-focus.

what I have been doing is a series of time-consuming F9 renders...is this about what everyone else has to do, too?

thanks!

J

Lightwolf
02-14-2004, 05:23 AM
Try the depth-of-field custom object. It is explaned in the LW 7.5 manual addendum.
If you have any Q's on it, feel free to post them (I contributed it).
Cheers,
Mike

Aegis
02-14-2004, 09:37 AM
You can use shift+F9 to get a very quick OpenGL preview of your DOF.

Also note that the Lens F-Stop quite often has to be a very low value (0.01 -> 0.1) to get any noticeable depth-of-field - I often start with a very low number and work my way up to get just the look I want.

Johnny
02-14-2004, 09:54 AM
OK..I'll try that when my screamer session finishes..

is there a way to know which number will give you the range you desire, or is it all trial and error?

J

Aegis
02-14-2004, 11:00 AM
I'm pretty sure there's some kind of formula you can use but I'm not a big fan of maths :D I normally just eyeball it.

As Lightwolf said you can use the DOF custom geometry object to get the Focal Distance just right - the F-Stop you'll have to tinker with.

klak
02-14-2004, 07:01 PM
There is a good explanation of computing focal distances for DOF
in the LW 6 Manual, Motion: Animate & Render, Chapter 7.13.
It is shown there how to use the Pythagorean theorem to determine the exact value for the Focal Distance.

Right now im too lazy to type the whole text down here...
but if you dont have LW 6 or the manual let me know.

cheers

Johnny
02-14-2004, 07:34 PM
Originally posted by Lightwolf
Try the depth-of-field custom object. It is explaned in the LW 7.5 manual addendum.
If you have any Q's on it, feel free to post them (I contributed it).
Cheers,
Mike

OK..I'm missing something here...I have 7.5 manual update, and see where they talk about Shift-F9 but Shift-F9 does nothing for me; I'm have my mouse over a viewport in Camera view...gettin' nothing when I hit Shift-F9. I have LW 7.5c running, and my DOF for my camera IS turned on.


The Custom Objects explanation in that online helpfile doesn't really clarify things..

Any hints?

Thank you!

Johnny

klak
02-14-2004, 08:14 PM
well, the explanation is in the LW7.5update pdf:

add a null-object, and apply the Depth-of-Field-Display Custom Object from the nulls Properties page.
Parent the null-object to the camera (Parent in place = off) and you should see a bounding box which shows the area in focus determined by the dof-settings of the camera.
When you select the camera its the blue dotted lined box named "Focus".
Now you can change the Lens F-Stop value of the DOF and the box changes accordingly.

klak
02-14-2004, 08:23 PM
i forgot to mention...you have to close the cameras properties page after you changed the Lens F-Stop or the Focal Distance value to have Layout update the bounding box :(

Johnny
02-14-2004, 09:10 PM
does "Parent to camera" mean that the camera is the parent to that null, or the null is parent to the camera?

J

klak
02-14-2004, 09:26 PM
it means:
select the null, hit the m-key (motion-options) and select the Camera as "Parent item".

brtk
02-14-2004, 10:58 PM
Just a quick setup example. BTW: to parent A to B means to make A a child of B. In this example "Your_null" is a child of "Camera".

Johnny
02-14-2004, 11:40 PM
thank you for that!
crystal clear now; I have it working.

J

pixelinfected
02-15-2004, 03:09 AM
dof is a painful part of all 3d software, a basic dof can be done into the 3d software, but if you want to work with more freedom is better to do in a postpro software, or in a retouch software (if you work on single image).

You can export easely a depth map which allow you to do a good depth of field add, with out pain and time waste from infinite test.

depth of field in rendering can be a time waster be cause it's slow, and not often enought clear to understand the focus zone.

and if you do an error in render, you must delete all work, if you do in postpro, in a few second you can change and recover the error.

my 2 cent

Johnny
02-15-2004, 08:15 AM
Originally posted by pixelinfected
dof is a painful part of all 3d software, a basic dof can be done into the 3d software, but if you want to work with more freedom is better to do in a postpro software, or in a retouch software (if you work on single image).

You can export easely a depth map which allow you to do a good depth of field add, with out pain and time waste from infinite test.

yeah..I'm beginning to feel that pain. My sequence with DOF took about 24 hours; without, it took 8-10hrs!!

Is there a tutorial for doing what you suggest with a combination of LW and FCP or Cinepaint?

J

Lightwolf
02-16-2004, 02:31 AM
Originally posted by klak
i forgot to mention...you have to close the cameras properties page after you changed the Lens F-Stop or the Focal Distance value to have Layout update the bounding box :(
Yep, unfortunately. If you edit the values in the graph editor (if you have envelopes applied), it will update instantly though. Don't ask why :rolleyes:

You can always do the "frame forward, frame backward" routine with the cursor keys, that way you won't have to close the camera panel.

Cheers,
Mike

Johnny
02-25-2004, 01:51 PM
Originally posted by pixelinfected
You can export easely a depth map which allow you to do a good depth of field add, with out pain and time waste from infinite test.

If you have a moment, could you explain how this is done? I don't see mention of it in the manual; maybe I'm not looking in the right spot, but scanned map and DOF, and don't see it..

thanks for the help!

J

pixelinfected
02-26-2004, 02:15 AM
you can export depth map by many lw export embedded in image or like separate pass, for example :

-embedded in image (you need an option on postpro software to extract it)

extended rla export
extended rpf export
deluxe rla export

- single pass export (with every post pro software you can handle)

render buffer export
psd export
buffer saver (free plugin)
Asa buffer saver (free plugin)


for example use render buffer export and render out depth channel, you can see as a white objects in a black fog. the intensity of pixel luminosity set the distance.

load in aftereffects, or photoshop to try
open original final render and depth map.

duplicate a layer of original render and blur it.
go to depth and go to channel, duplicate the blaxk channel

now you can load from it the channel like selection to cut out part which must not blurred.

after effects (more simple)
load image and depth map
you can have two way, if you have a dof plugin (image lounge collection, frischluft dof, or production bundle) you select image, apply filter and select depth image like controll for plugin.

if you not have it.
you duplicate image original, blur upper image and use depth map like mask to cut correctly the blurred image.
i hope that help you.

Johnny
02-26-2004, 02:20 AM
Originally posted by pixelinfected
after effects (more simple)
load image and depth map
you can have two way, if you have a dof plugin (image lounge collection, frischluft dof, or production bundle) you select image, apply filter and select depth image like controll for plugin.

if you not have it.
you duplicate image original, blur upper image and use depth map like mask to cut correctly the blurred image.
i hope that help you.

I think so! thank you...Seems like I could do this with CinePaint, tho more laboriously without this DOF plug-in, don't you think?

J

pixelinfected
02-26-2004, 03:20 AM
i never use cinepaint, but if it can handle alpha, and blur filter, you can do.