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Profane
02-28-2004, 02:07 PM
Hi folks!I'm using Mental ray depth of field...the thing is that my renders are not so good...I mean the blur effect is not 'smooth'/''soft' it's kinda 'noisy'...What parameters should I change in the render globals settings to achieve better results?
Thanks.

bmcaff
02-28-2004, 03:59 PM
First reduce the RGBA contrast setting, default is 0.1, try reducing to .01. If the image is still noisy increase the sampling to 1,3. If this is stilll not good enough then try 2,3(or 4). But really DOF increases the render time so much that it's just not worth it. You should do this in Post. Something like Irisfilter or Frischluft lenscare plugins produce fast, reasonable results (they cost though).

alivegy
02-28-2004, 06:40 PM
Another vote for rendering a depth map and then bluring in post. It takes waaaaaaaaay too much time to render DOF, and with it in post you can change the blur on the fly rather than having to rerendering.

Profane
02-28-2004, 07:31 PM
ok...thanks guys i'm gonna see what'll happen.

Profane
02-29-2004, 10:54 AM
Originally posted by alivegy
Another vote for rendering a depth map and then bluring in post. It takes waaaaaaaaay too much time to render DOF, and with it in post you can change the blur on the fly rather than having to rerendering.

...How can I render a depth map in MeNTAL Ray....?
is Depth map the alpha channel?

lazzhar
02-29-2004, 11:02 AM
It's the z-depth channel, just check it in render global. then render to maya .iff file so when you open the result in fcheck press z in your keyboard to see the depth channel.

There is a shader in highend3d for that purspose but it works only with maya renderer.

Here is some useful definitions :
http://www.thegnomonworkshop.com/tutorials/passes_layers/passes_layers.html

Cheers.

Profane
02-29-2004, 03:25 PM
Originally posted by lazzhar
It's the z-depth channel, just check it in render global. then render to maya .iff file so when you open the result in fcheck press z in your keyboard to see the depth channel.

There is a shader in highend3d for that purspose but it works only with maya renderer.

Here is some useful definitions :
http://www.thegnomonworkshop.com/tutorials/passes_layers/passes_layers.html

Cheers.
I did what you said before....I opend fcheck press z but actually fcheck says:No z-buffer....what's wrong???help!

Emmortal1
02-29-2004, 10:58 PM
Kind of off topic, but anyone know some good DOF plugins for Shake? I'm assuming the ones mentioned were for After Effects.

alivegy
03-01-2004, 08:22 AM
I believe highend 2d has a shake script written just for handeling maya's iff depthmaps. It works farily well, but is only as good as the depth maps that maya produces.

lazzhar
03-01-2004, 12:14 PM
>>I did what you said before....I opend fcheck press z but actually fcheck says:No z-buffer....what's wrong???help!

That's because you didnt turn on the z-depth in render global.

For Shake and dof, I never used Shake but it should has a similar workflow like Combustion where you can extract the z-depth then use it as a mask for a blur.

Profane
03-01-2004, 02:49 PM
i did it!http://www.threedy.com/site/forum/attachment.php?s=&postid=166173

lazzhar
03-01-2004, 04:26 PM
Yes Profane, it happens for me sometimes. To get rid of that I usualy open the camera attributes and turn on z-depht from there.
For now, try render from the persp and see if you could get the z channel.

Emmortal1
03-01-2004, 06:08 PM
Ya Shakes can utilize Maya's DOF but it's kind of a pain to get right as Maya's Z-depth isn't like any other 3D packages in the way it's caclulated. I'm all about plugins and if there is one to make my life easier then I'll use it. Just wonderin if anyone knew of any. Thanks,

Emm

Profane
03-01-2004, 08:58 PM
Originally posted by lazzhar
Yes Profane, it happens for me sometimes. To get rid of that I usualy open the camera attributes and turn on z-depht from there.
For now, try render from the persp and see if you could get the z channel. .... ... it doesn't work even in this way!!!I'm so down!!!!


what's wrong??!!!! :cry: :cry: :cry: :cry:

lazzhar
03-01-2004, 09:02 PM
T'es un homme, faut pas pleurer !! lol

Look, post your file (or a similar one) and let us see if someone could help. If I remember i'll post one tomorow.

devdoka
03-03-2004, 02:11 AM
Hi all,
sorry for my post here.This is a reply to Emmortal1.


Emmortal if it troubles you to "normalize" the maya depth the way shake reads it,I suggest
you should try to download some macros
from highend2d.com.
2 of them from Kurgan.
mayaZblur and mayaDefocus.
There is also one from Peter Warner,
MayaDepthKey.

-Dennis

lazzhar
03-03-2004, 05:30 PM
I've attached a test scene where just you render (or batch render) and you'd get your z-channel working.

Profane
03-03-2004, 06:18 PM
:cry: :cry: :cry: :cry: still nothing....I think it's my maya that has some bugs!

lazzhar
03-03-2004, 06:35 PM
How do you open your rendered picture?
Look, just render, then go to your /images directory and open the file from there and let me know.

Profane
03-03-2004, 06:51 PM
I did it precisily in that way....:shrug:

lazzhar
03-03-2004, 07:00 PM
I'm really sorry I dont know what's wrong. Maybe someone can download the file and tell us if it works?

Profane
03-03-2004, 07:21 PM
yeah...may be....
thanks anyway for your help.:beer:

Emmortal1
03-04-2004, 01:39 AM
Dennis: It's not that it troubles me in any way, but I'm all about speed and workflow. If there is a tool out there to make my life easier then by all means I'll use it. Thanks for that information, I'll definitely check those macros out.

Profane
03-05-2004, 07:23 AM
is what i'm doing right?
http://www.threedy.com/site/forum/attachment.php?s=&postid=168038

lazzhar
03-05-2004, 10:34 AM
That's the reason!
Dont save your rendered picture like that. As I suggested, just go to the folder where your maya save the pictures after rendering then look to the last file created, open it and you're happy with your z-depth ;)
Or just batch render.
Cheers.

Profane
03-05-2004, 01:06 PM
:bounce: :bounce: :bounce:
I'm so happy...that was the reason!!
I was a complete jerk!!!

Thanks for your help and your time!

CONDE3D
03-05-2004, 04:35 PM
Hi, Profane, maybe the .iff format don't support z-depth channel (I'm not shure). Try .rla extension or .pic (softimage format)... I use RLA and works well.

Good luck!

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