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RafiS
03-17-2006, 09:53 PM
Hi,

I've attatched a render of a scene I'm doing....I haven't done any texturing or lighting (ok, only a little bit but I'm going to work on that later). But the picture doesn't look good. Its a scene where someone is looking down from a rooftop and CAN'T see right to the ground.

But in the render the bottom of the building is still sharp....I want it to sort of blur as it goes to the bottom. I made the buildings that way by stretching them in modeler so they look like they are angular and I like the effect, they are really long and in the scene, the camera goes down, towards the ground, so I need a sort of blur that can be animated.

I tried to add depth of field, but that just made the entire image blurred and I just want it to sort of be less clear the more you look towards the bottom.

Does that make sense....sorry, I'm not really good at this but I want it to look good....any advice, or if someone could tell me of a tutorial where they tell you how to do something like this would be really good.

Thanks,
Rafi.

RafiS
03-17-2006, 09:56 PM
I forgot to attach the image....

Eclyps19
03-17-2006, 10:24 PM
well i don't remember 100% how to do this since i havent used DoF for a long time but make a null, go to the properties of it and add "rangefinder". double click that and make it find the range to the camera. that'll give you the distance. put the null where you want the clearest spot to be. The null will then show that number. go into the DoF properties and change the focal distance to that number. you may have to mess with the F-stop to get things just right but that should get you to blur the bottom of the buildings.

Someone please correct me if i am wrong.

kevman3d
03-17-2006, 10:38 PM
Yup - You need to set the focal distance, however you also need to set the F-stop so that the flur occurs at the bottom too... Here's how you can get a good visual feel for the effect.

The old rangefinder approach works - But since LW7, its been unnecesary as LW now visually displays the focal distance for you (but only in the ortho viewports)


Switch to an orthographic viewport (ie. Left/Right/top/front/etc view).
Activate DOF for the camera
You can see the Focal distance appear as a dotted 'circle' showing you where the focused point will be.

That's the easy way to set up DOF, but it won't show you the area in focus.

For that, add a NULL object and parent it to the camera. Make sure the null is centered in the camera (so if you've parented it using 'Parent in place', select the null, click on 'Move' and then under modify Tab, click 'Reset' to center it)

Press 'p' for the Properties panel for the Null. Add a Custom Object (first tab in the panel) - 'Depth of Field Display'

Now you can get a nice visual on where the DOF will appear that shows you the area that is in focus (and you can see it also in the Perspective viewport) in the camera view! :thumbsup:

Tweak the focal distance to move the focused area back and forth, and then tweak the F-Stop to adjust the size of the focused area (NOTE: F-Stop changes don't update instantly, like Focal distance... Once you've adjusted it, just slide the time slider back and forth to refresh the display)

The nice thing with this tool is that it shows you the effect on DOF as you tweak the zoom, F-Stop and more. Just remember the update the display if things don't look they're changing by adjusting the frame back and forth on the slider... Simple.



Kev.

kevman3d
03-17-2006, 10:46 PM
Its not DOF, but just a quicky suggestion to perhaps consider a little ground-fog to add some 'haze' to your buildings far below. Ground fog, or just normal fog could add a little to the feel of the scene as well...

RafiS
03-18-2006, 06:04 AM
Hey,

Thanks a lot for your reply....I'll try and see if I can make it look right.

RafiS
03-18-2006, 06:09 AM
Hey Kevin,

Was so happy when I saw you....and thanks for your detailed reply....I sorta laughed when I saw you'd gone through all the steps....cus I was like I'm sure he thought that he should cus he knows me and knows I won't really know what to do.

Anyway, about the depth of field....I was able to do it with all those steps - seriously, those were really detailed. I played around with the two different things and realised what was used for what.

Only, I have a few more problems. I've attatched two more images. One with depth of field....now, that's the setting I sorta want....its cus it means the top part is not that blurred but the bottom part is....the only thing is that it hasn't really made a big difference to the bottom - you can still see the base....and I sorta wanted it to not be clear at all, but still maintain some detail - that it was a building.

The other thing is with the fog....I figured how to do it and even played around with the other fog setting, but yeah, from this camera angle the fog on the ground looks a bit wierd....like a flat polygon with low opacity, is there a way to 'blend' it in so it doesn't cut off like that.

RafiS
03-18-2006, 06:10 AM
I've made the fog green so you can see.

kevman3d
03-19-2006, 01:06 AM
Yup - Spread the minimum and maximum distance values apart in fog a lot more (I'm talking about the standard LW fog (ground fog is a little trickier) - If you need to know more on Fog, I actually have a PDF about standard LW fog on my website.)

The Foggiest Idea is here... (http://www.kevman3d.com/lightwave.asp?section=tutorials)

Also, I noted that you can see that there are no buildings behind the middle one - I'd suggest building some basic boxes or copying the buildings and placing in a few more just to fill out the scene a little more...

As for DOF - You need a smaller F-Stop to increase the Blur factor - You can adjust the DOF display so that the 'infocus area' is up at the top using the Focal distance...

If you're camera is static, you could also consider a still image as a background, then fake the DOF in photoshop. Also, if you planned on compositing the project together later in say, After Effects, you could render out the background as a separate sequence to your character, and produce the DOF effect using gaussian or compound blurs... Check out these two tutes.

DOF using a depth map and compound blur in AFX (http://www.bernardlebel.com/tutorials/AFX_depthPassDof/DOF.htm)
DOF in Aftereffects (http://www.chantiergraphique.com/faking_DOF2/)

Kev.

Anti-Distinctlyminty
03-19-2006, 03:32 PM
For easy manipulation of DOF, you can use a Null to control it.
Use the method that kevman3d outlined above to add the 'Depth of field display'.

Again, make sure 'parent in place' is off. Add another null object, call it DOF_Ctrl or something and parent it to the camera (so the null is a child of the camera). Switch its controls (in the bottom left of the screen) so that you can only move it in the z direction - disable the x and y directions. Disable all the rotation (heading, pitch and bank), then disable all stretch directions except z.
You should now have a null that can only be moved and stretched in the z direction.
Now bring up the cameras properties panel and click on the 'Stero and DOF' tab. Set the 'Focal Distance' and 'F Stop' to 0. Click the 'E' button next to 'Focal Distance' to bring up the graph editor for the focal distance. Click on the 'Modifier' tab, then select 'Channel Follower' from the 'Add Modifier' drop down list.
Double click on the 'Channel Modifier (none)' that should now be in the list
to bring up the selection panel. Now from this panel, select the DOF_Ctrl.Position.Z, click OK and close the graph editor.

Now, the focal distance will be controlled by the DOF_Ctrl null object's Z position. Play around with the position of the null and see the Depth of Field Display change.

Now, do the same thing as above for the F-Stop envelope, but use the DOF_Ctrl.Scale.Z to control that. So you now have complete, keyframe-able control over the focal distance and F stop.

If you want the ground to be blurred but not the object in the foreground, just reduce the F stop.

PixelInfected
03-21-2006, 12:11 PM
light is bad, too flat, try to restart with single point light with very large fall off, an opposite light for reflection, with a small falloff, and a large area light at top of buildings for a soft shadow.

RafiS
03-22-2006, 04:21 AM
Hey guys,

Sorry I didn't reply earlier....I've started this course using Maya and its a pain cus I don't like going through Maya....I really miss lightwave. The program looks so much better and serious. Anyway, haven't really had time to go through the things you guys talked about.

Kevin, about the scene, its actually a animated scene so I can't really do it in after effects, but thanks for the tutorials....I've never really known how to get things in after effects and put them together so this will be good.

About your tutorial....I looked through it really quickly and I'll look at it when I have more time with my lightwave thing. I played around a little more with the focal distance and all and it made a little difference but not a lot. I dunno....its a really fast scene so it won't make a big difference, but I still wanna do it just so I understand it.

RafiS
03-22-2006, 04:22 AM
For easy manipulation of DOF, you can use a Null to control it.
Use the method that kevman3d outlined above to add the 'Depth of field display'.

Again, make sure 'parent in place' is off. Add another null object, call it DOF_Ctrl or something and parent it to the camera (so the null is a child of the camera). Switch its controls (in the bottom left of the screen) so that you can only move it in the z direction - disable the x and y directions. Disable all the rotation (heading, pitch and bank), then disable all stretch directions except z.
You should now have a null that can only be moved and stretched in the z direction.
Now bring up the cameras properties panel and click on the 'Stero and DOF' tab. Set the 'Focal Distance' and 'F Stop' to 0. Click the 'E' button next to 'Focal Distance' to bring up the graph editor for the focal distance. Click on the 'Modifier' tab, then select 'Channel Follower' from the 'Add Modifier' drop down list.
Double click on the 'Channel Modifier (none)' that should now be in the list
to bring up the selection panel. Now from this panel, select the DOF_Ctrl.Position.Z, click OK and close the graph editor.

Now, the focal distance will be controlled by the DOF_Ctrl null object's Z position. Play around with the position of the null and see the Depth of Field Display change.

Now, do the same thing as above for the F-Stop envelope, but use the DOF_Ctrl.Scale.Z to control that. So you now have complete, keyframe-able control over the focal distance and F stop.

If you want the ground to be blurred but not the object in the foreground, just reduce the F stop.

Hey,

Thanks for going through this in all these steps....I'm sorta new to lightwave so when people say things I don't really know what they're saying. So thanks for going through all these steps....I did a little but I'll do it properly and post the pictures.

RafiS
03-22-2006, 04:24 AM
light is bad, too flat, try to restart with single point light with very large fall off, an opposite light for reflection, with a small falloff, and a large area light at top of buildings for a soft shadow.

Thanks for your advice, I was just doing some tests so I wasn't really looking into the lighting and all but still, thanks for going through what to do. I'm not really good at lighting, and have a book that I have to read....there's so many things I'm not really good at in lightwave. Anyway, I'll posting pictures to get more advice.

Anti-Distinctlyminty
03-22-2006, 04:40 PM
...Thanks for going through this in all these steps....I'm sorta new to lightwave so when people say things I don't really know what they're saying...

I know the feeling, that's why I explained it step by step. I know how frustrating it can be when you just don't understand the advice people have given :)

allenbussell
03-23-2006, 01:48 AM
DOF in LW...I don't do it anymore.

I recommend using DOFPro from http://www.richardrosenman.com/dofpro.htm

Works so much better and has a lot more control (IMHO)

RafiS
03-23-2006, 02:50 AM
Thanks....I'll have a look and try and use it.

kevman3d
03-23-2006, 09:29 AM
DOF in LW...I don't do it anymore.
I recommend using DOFPro from http://www.richardrosenman.com/dofpro.htm
Works so much better and has a lot more control (IMHO)

I agree - That's a really Nice plugin for DOF effects on still images...

However, its for Photoshop, which imho is probably not the most suitable Animation compositing solution. The beauty of compositing software is that you can 'tweak' and fiddle with the look of the effect in near realtime without creating image effects prior.

Post-processing images in Photoshop sorta defeats that one. lol! :D

But definitely worth a look - it does really nice DOF effects for images.

Shaun_michael
03-23-2006, 12:32 PM
I use Lenscare plus z-buffer for my DOF in combustion.


http://www.frischluft.com/
S.

allenbussell
03-23-2006, 02:04 PM
I agree - That's a really Nice plugin for DOF effects on still images...

However, its for Photoshop, which imho is probably not the most suitable Animation compositing solution. The beauty of compositing software is that you can 'tweak' and fiddle with the look of the effect in near realtime without creating image effects prior.

Post-processing images in Photoshop sorta defeats that one. lol! :D

But definitely worth a look - it does really nice DOF effects for images.

You're right - I do very little animation - mostly still shots. No matter the tool though - DOF is less painful in post vs. any 3D program. I really need to get AfterAffects and learn that package.

Anti-Distinctlyminty
03-23-2006, 02:23 PM
kevman3d, you can also use the Digital Confusion pixel filter. Press Ctrl-F8 to bring up the processing tab and select digital confusion from the bottom drop down list. It has several options and you will have to use the same method to get the DOF focus and F-Stop to track properly that I described before (by using the graph editor). Its exactly the same, but, as its a post process it doesn't matter about how many AA passes you do. Especially useful if you want good DOF in an animation with many frames & don't want to wait for all those AA passes. You can use a combination of both, a few AA passes and digital confusion will give a nice result :)

jeremyhardin
03-23-2006, 05:36 PM
hmm. I honestly thought that this being right next to the iDof thread for days might lead to some natural discussion without any plugging my own stuff.

it didn't, so here I am.

with iDof, you can generate a better DOF depth matte and use it in Photoshop, Depth of Field Pro, or any Compositing App. And since you can animate the black point in LW, you can get animated DOF effects, even with Photoshop batch processing or Depth of Field Pro batch processing.

And if you want to blur it in LW instead, just set the iDof channels plugin to overwrite the alpha channel, then add iDof post blur. You never have to mess with focal distances or fstop. Just an object for your black point, and an object for your white point.

there's a free 10-day trial here, as well as the documentation:
http://www.lwidof.net

and a minitut for DOF compositing in after effects here:
http://www.spinquad.com/forums/showthread.php?p=123727#post123726

kevman3d
03-26-2006, 03:09 AM
you can also use the Digital Confusion pixel filter. Press Ctrl-F8 to bring up the processing tab and select digital confusion from the bottom drop down list.

Hmmm, Digital Confusion was a great idea - However, while they improved it in LW8.3 (or was it 8.5?), I'd still recommend a depth-post approach, simply for the realtime tweakability, rendering time savings and also to avoid all the possible artifacts it can generate (like popping surface transparencies being one that is particularly annoying in animation).

As for iDof - Jeremy's post-process system looks promising - Will give the demo a whirl later on... :)

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