Creating HDRIs with Terragen and VRAY

thomthom

Often you want to sample down and blur the HDR you use for GI lighting to avoid artefacts.

AcesHigh

Screenshots?

01
from the ground

02
from above, but close

03
from above, very far away (cant even see the ball anymore. Notice the artifacts pattern REMAIN THE SAME, its constant, no matter the distance!!!!

thomthom

Odd. Try blurring the GI HDR you use? Don't have to do anything to the Background HDR though.

AcesHigh

@thomthom said:

Odd. Try blurring the GI HDR you use? Don't have to do anything to the Background HDR though.

blurred it to 50. Nothing changed.

I was mistaken. Setting the bitmap multiplier at 50 brightened up the image, but the artifacts persisted.

thomthom

Might be that Terragen has generated some extra bright pixels...

remus

You could try the HDR in another app to see if its an issue with vray or with the HDR itself

AcesHigh

@thomthom said:

Might be that Terragen has generated some extra bright pixels...

I wonder why they dont show up in the image when viewing it at HDRShop or Photoshop. It only happens in VRAY. I followed some tutorials on the net to make the HDRs... neither mentioned it, but neither mentioned VRAY either

AcesHigh

@remus said:

You could try the HDR in another app to see if its an issue with vray or with the HDR itself

do you have any suggestion of app for me to try it?

thomthom

@aceshigh said:

@thomthom said:

Might be that Terragen has generated some extra bright pixels...

I wonder why they dont show up in the image when viewing it at HDRShop or Photoshop. It only happens in VRAY. I followed some tutorials on the net to make the HDRs... neither mentioned it, but neither mentioned VRAY either

Would be that it's just a single pixel. And Photoshop should only display certain colour range, but V-Ray uses the whole range to calculate the light.

remus

Kerkythea is the first one that springs to mind. Indigo might be able to do it, but youd have to convert to .exr first, which might do weird things.

sepo

Also try in LightUp...

AcesHigh

@sepo said:

Also try in LightUp...

tried in Lightup... no artifact appeared, but I suppose Lightup dont really uses HDRI images... I mean... it works the same for .HDR or .JPG images!