Why does this picture look so bad

Become a member of the CGSociety

Connect, Share, and Learn with our Large Growing CG Art Community. It's Free!

THREAD CLOSED
 
Thread Tools Search this Thread Display Modes
  03 March 2006
Why does this picture look so bad

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.
 
  03 March 2006
I forgot to attach the image....
 
  03 March 2006
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.
 
  03 March 2006
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!

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.

Last edited by kevman3d : 03 March 2006 at 10:43 PM.
 
  03 March 2006
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...
 
  03 March 2006
Hey,

Thanks a lot for your reply....I'll try and see if I can make it look right.
 
  03 March 2006
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.
 
  03 March 2006
I've made the fog green so you can see.
 
  03 March 2006
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...

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
DOF in Aftereffects

Kev.
 
  03 March 2006
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.
 
  03 March 2006
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.
__________________
Danger! Mad Scientist at work
I'm a mad genius, a mad scientist, someone like dr. jeckill and frankestein with a bit of Bugs Bunny.
 
  03 March 2006
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.
 
  03 March 2006
Originally Posted by Anti-Distinctlyminty: 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.
 
  03 March 2006
Originally Posted by PixelInfected: 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.
 
  03 March 2006
Originally Posted by RafiS: ...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
 
Thread Closed share thread



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
CGSociety
Society of Digital Artists
www.cgsociety.org

Powered by vBulletin
Copyright 2000 - 2006,
Jelsoft Enterprises Ltd.
Minimize Ads
Forum Jump
Miscellaneous

All times are GMT. The time now is 09:52 PM.


Powered by vBulletin
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.