Scene capture2d causing blurry/ghosting artifacts

hello i work in my own race game, but i found a great problem, in udk3 i use a regular scenecapture to provide real reflection in the car retrovisors, but in UE4 when i use the same trick all are motion blur in extreme, even when i disable all motion blur, the scenecapture2d, the camera attach to my vehicle and the post process, all are disable but still remain.

check this video to see the problem, in the video: left part show us a ugly ghost effects from the capture, and the right hand the correct visualization but without capture and of course without cool retrovisor reflections u_u

here: unreal engine ugly blur - YouTube

I second this.

I have tested this in several projects and several templates, and each one gives the visual problem described above. You dont even need to have an object with scene capture material applied in the level, as soon as you plug a texture target to a Scene Capture 2D actor in the level and play, it starts to occur.

The blurriness only seems to disappear when both motion blur and temporal AA are disabled in the global post process volume, but of course it doesnt give an acceptable result…

i am scare bro! i have 2 days with this

Hi ZkarmaKun -

I am watching your video and I am not seeing any persistent rear view mirrors in the video, but I do understand the error you are getting but to confirm if you could give me a new video just highlighting the error.

Thank You

Eric Ketchum

hi Eric, i upload a new video show us all process, check!, i use the scene capture to get real reflection on my left retrovisor, and begin the problem itself

here: UE error highlight - YouTube

Hi ZkarmaKun -

Have you tried to see if the rendertarget texture size has been increased from the default 256x256 to something larger? Does that remove the ghost effects or jitteriness you are seeing?

Thanks

Eric Ketchum

ZkarmaKun, can you also tell us what your GPU is please? I’ve started to think that this is cause by low performance. I have a GTX 460 so i think a scenecapture 2d combined with Temporal AA of the global PP is too much for it. :\

Hi Eric, i try that in 1k and 2k, still same, also change other configs, clamp textures, no midmaps and other, always same., and anyway with large res i simple kill my performance my optimal res are 64x64 for this little reflection i need, because ssr no work properly in this specific case

greetings!!!

jeje its no perforce, first i try with a gtx 650 ti, then a try with a 660 ti, and finally i try a gtx titan!!!

Well now this makes it more complicated then. I’d be more relieved if i knew it was a performance issue on my side…lol

Hi ZkarmaKun -

I am still not able to reproduce the blurrying effect here. I do see a Pixel shift when LODs are rendered in the Scene Capture as you are moving which can great a jitter effect. From my test though most of that disappears at high Texture Size. You will have to balance higher texture size with amount of pixel jitter.

Thank You

Eric Ketchum

HI Eric.
is very easy to reproduce, i try your tips, but still remain, maybe i do something wrong, can i send you my project?, maybe you can fix?.

anyway i am very thanks for your support.

Hi ZkarmaKun -

For Legal reasons we don’t except whole projects, but if you wanted to upload to Dropbox a copy of the actual car blueprint asset I can look at it for you.

Try this also:

Go into the BaseEngine.ini file and find the following 2 lines:

bSmoothFrameRate=false
SmoothedFrameRateRange=(LowerBound=(Type=“ERangeBoundTypes::Inclusive”,Value=5),UpperBound=(Type=“ERangeBoundTypes::Inclusive”,Value=120))

And Change them to:

bSmoothFrameRate=true
SmoothedFrameRateRange=(LowerBound=(Type=“ERangeBoundTypes::Inclusive”,Value=5),UpperBound=(Type=“ERangeBoundTypes::Inclusive”,Value=60))

See if this fixes the problem.

Thank You

Eric Ketchum

hi Eric actually i just try your last tip, its not work, nothing change. i share my bps with you, i hope you can fix, i am down of ideas

here Dropbox - Error

thanks

Hi ZKarmaKun -

I have had some success in changing the setup of the render target material and setting it to emissive and unlit. Try that and see if it looks a little better for you.

Thank You

Eric Ketchum

Hi Eric
sorry even with that the problem still remain, i try all blendables anyway
maybe you can fix in the next release.

greetings!

Hi ZkarmaKun -

You problem does not lie with your SceneCapture Actor but in a duplicate mesh in your blueprint setup. Your blur is being created by two meshes being rendered right on top of one another, but offset by the physics of the start and stop motion. If you look closely at your vehicle as it moves you will see a Doppler effect around the entire mesh which also creates a blur when two render targets separated by the time based dilation of physics create an illusion of blurriness.

I believe your Root Mesh is never going invisible as you have it set up in your event graph which is where the two meshes are coming from. Try to use only the Root mesh and remove the Interior mesh and you problem should solve itself.

Thank You

Eric Ketchum

hi eric
i was do that, i remove even all funcionallity in BP, this weekend i make a video for reproduce the problem in your example content, as User: Jacky say the problem itself begin just when you connect the very imagetarget to scenecapture, before that all is clean,

Greetings Eric, i thanks you for the support

yes is how a doppler by physics but is no mesh problem, the very first time to happen, i just have the root mesh

Hi ZkarmaKun -

I haven’t heard back from you in a few days so I am going to mark this as the accepted answer to the question for tracking purposes. However, if this problem has persisted or returns and you can provide that sample project example feel free to respond and I will look further into this for you.

Thank You.

Eric Ketchum