Shadow quality problem in the distance

Hi,
I have troubles with dynamic shadows in my current project. The shadows from my moveable directional light are loosing detail when the camera is moving away from my object.

I tried to adjust every parameter in the “Cascaded Shadow Maps” section. (I am using the BP_LightStudio). But I could not solve the problem. I have to increase the area in which the shadow have full detail. Adjusting the “Dynamic Shadow Distance MovableLight” parameter had no noticable effect.

Are there perhaps some parameters in the Unreal Engine config file which I can adjust?

Best regards, Andreas

Hello Maxwell_77,

So from what you describe you are having an issue with your shadows with your movable light, as you move away from an object. You tried to adjust some options but with no results.

If you would please post a screenshot or link a YouTube with this issue happening.

I do have a few questions for you along with the linking of your screenshots.

1.) Can you link me you DxDiag?
2.) Can you reproduce this in a fresh project?
3.) Can you reproduce this in 4.9?

After all of that it should be much easier to narrow down the list of possibilities of where the problem is.

Thank you,

Hi ,
thank you very much for your answer. Unfortunately I cannot use version 4.9 because I am using the NVIDA Gameworks build with VXGI.

I have attached two photos where you can see what I mean. Although I tried every parameter as described I was not able to solve this problem.

Best regards, Andreas

58703-far.jpg

Hello Maxwell_77,

So Cascade shadow maps cover the distance between your camera and your Distance field shadows.

So if you took your scene and scaled back your Cascade Shadow maps to a reasonable distance from the camera. Then you adjusted the values slowly. You will start to see the farther that the shadow map goes the less resolution you will receive.

It is common workflow to use Cascade Shadows to certain point and then allow for Distance Shadow maps to be used for further distances. Distance Shadows also have their limitations. So then after that your far shadows will allow for the extremely far shadows like far off mountains and the like.

With all of this in mind at a certain point this will increase the load on your project and increase FPS/GPU ect…

Please try the above mentioned steps starting with Cascade shadows and then applying further Types of shadows as needed.

Let me know if this helps and what you come up with.

Thank you,

Hi ,
thank you very much for the hints. I will try this tomorrow. Is there no possibility to edit special config values to archive what I need? I have no problems when this is reducing my framerate. At the moment I need the Engine to create animations.

Best regards, Andreas

Hello Andreas,

I was wondering if you had a chance to test this?

Thanks,

Hi .
today I had the chance to test your hints. Thank you very much for your help. I could improve the shadow quality, but the fade between the Cascade and the far shadows is always visible in conjunction with the loss of detail.

At the moment I try to figure out if I can use the Unreal Engine 4 for professional broadcast animations. But this dynamic shadow issue worries me. For this field of application we need a robust reliable shadow system.

I am convinced that the Unreal Engine 4 will be probably
used in the film business very often. Are there any plans to enhance dynamic shadows in the future?

Best regards, Andreas

Hello Andreas,

The last thing I can think to try is increase the number of Dynamic Shadow Cascades on your light source.

This is a link to our documentation on Shadow Cascades.

I have a test bed in 4.8.3 where I have my shadows set to a value of one for the Number of Dynamic Shadow Cascades. Then I increased that value to 4. After 4 you won’t see a great difference in quality, especially at a great distance.

These are the results.

This is at 1 cascades:

Notice how blurry the edges of the shadows are, even at a close distance.

This is at 4 cascades:

You can see the improvement in the quality of shadows because more calculations are taking place in order to draw them. You mentioned this was for a cinematic, so this performance hit will probably not apply to you. However, your FPS and CPU/GPU performance will take a hit.

Let me know if this helps,

Hi ,
your are right. To increase the Shadow Cascades helps in normal cases. I guess my claims are at the moment too high because I compare the Unreal Engine 4 render quality with raytracing renderers like V-Ray. As I told you I try to figure out at the moment if the Unreal Engine 4 quality can be a replacement for raytraced animations or be used for broadcast.

Thank you very much for your help. I appreciate this very much. I guess this information will help many others who have the same problems like me.

Best regards, Andreas