Setting up motion blur on car render- help needed

[kenia_orellana]

I think i posted my previous post in the wrong forum, so here again (Admin please delete the one at https://forums.chaos.com/forum/chaos...le-help-needed )

So here is my problem


Trying to set up a car render with motion blur, but i cant get it done correctly

Here is what i did so far

1. created a 3 frame scene
2. frame 0 i set a key for the car and the wheels
3. frame 2 i moved the car 5m and rotated the wheels on 180degrees
4. linked the camera and target to the body of the car

I tried multiple possibilities with shutterspeed, f-number and iso, but when only the complete car gets blurred

The goal is that only the wheels and the background/foreground gets the motion blur. The body of the car should be "crispy"

Here my camera settings



and here a test render, as you can see the vegetation is not blurred at all (using single meshes and some forest pack for the grass)



Note that I found a solution for the body of the car, did uncheck Default motion blur, inside vray object properties
But still cant get the background blurred
Scene should be similar to this:


Can someone help me to achieve this please?

[dimitar_panayotov]

Hi kenia_orellana. I reproduced your steps. You could check the links between the camera and the car. You should get something similar to the picture below when you open the schematic view. From what I'm seeing in your example, the camera stays static otherwise the vegetation should be blurred. You could also stretch the animation a bit. Check in the "Curve editor" if you have some in-and-out curves. For such a short move these might affect the result, so you might want to remove them from the animation. Put your desired shot somewhere in the middle of the animation.

[vladimir_krastev]

Hi you need to have the wheels rotating as well. Have you done that? Basically you have to animate the body and wheels to move down the road, the wheels rotating and the camera linked to the body.

After that you have to adjust the Camera Motion Blur Parameters or enable motion blur from the V-Ray settings in the camera tab.

[caypiranha]

... and keep in mind: in IPR mode Camera motion blur isn´t working anyway ( btw@Chaos: why not?) ... If you rely on that so far - wrong horse! =)

[kosso_olli]

... and keep in mind: in IPR mode Camera motion blur isn´t working anyway ( btw@Chaos: why not?) ... If you rely on that so far - wrong horse! =)

It has been like that for a long time. Sadly.

[kenia_orellana]

Hello

thanks for the help

The first issue I resolved was that i was using IPR, didnt know that it doesn't support motion blur

Now i did a quick and dirty render and the background is blurring. - see below




But as you can see, now the body is blurred again, although i did disable it within the vray object properties



Very weird, can you tell me what i'm doing wrong, dimitar_panayotov can you send me a screenshot of the settings you used?

For clarification: I did linked the camera and also did rotate the wheels

Thanks again for the help

[kenia_orellana]

i was investigating more, found a post where it stated to turn the moblur duration to 0
Did that, but with the same results
Using vray6 hotfix 2 - is this a bug???

[caypiranha]

please check again, where your Cam is linked to.. =)

I almost use a helper object (Point), where everything is linked that belongs to the Car and this includes also the Cam. That makes sure everything moves together.

I wouldn't touch anything in the Vray Properties. Keep it for the moment all default. It should work just right if everything else is fine!

[kenia_orellana]

please check again, where your Cam is linked to.. =)

I almost use a helper object (Point), where everything is linked that belongs to the Car and this includes also the Cam. That makes sure everything moves together.

I wouldn't touch anything in the Vray Properties. Keep it for the moment all default. It should work just right if everything else is fine!

Hello caypiranha

i had the camera and target linked to the body of the car, Creating a point, linking the whole car to it and then linking the camera and target to the point and setting vray properties back to default did the trick

Thanks again to all of you who helped me with this

[caypiranha]

Glad you made it! =) Your Car hs been already grouped. Maybe its only the Body with interior components. But I would never group the wheels rig underneath as well. group the Points all together - that's fine! =)
Grouping is bringing you mostly in trouble. I had bad wobbling wheelmotions in moblur, until I killed all groups and used points only...some frustration for me probably as you had here =)

[kenia_orellana]

Glad you made it! =) Your Car hs been already grouped. Maybe its only the Body with interior components. But I would never group the wheels rig underneath as well. group the Points all together - that's fine! =)
Grouping is bringing you mostly in trouble. I had bad wobbling wheelmotions in moblur, until I killed all groups and used points only...some frustration for me probably as you had here =)

yeah, i was close to pulling out my hairs

I did watched a lot of tuts on youtube, but none of them where pointing out to link the car parts to a point.

Here the results - still need to finetune light et cetera, but now it's easy

Thanks again for your help

[caypiranha]

Here the results - still need to finetune light et cetera, but now it's easy

cool!... and the more fun part maybe!

[kenia_orellana]

yeah, now it's fun

thought to share the final render. Thanks again to all of you who helped me with this