LW Render cutting out lines

[gpowless]

Hello ArchiTalkers,

To cut to the chase......

I have been at this for many years and all of a sudden the Lightworks renders seem to cut out some of the lines that should be enhanced by shadow lines. Any idea what I'm doing wrong?

[Thomas Holm]

Maybe these boards have jaggies from the saw mill? 😉

Looks like a resolution issue to me. Try increasing pixel count or anti-aliasing.

[gpowless]

I tried altering both to no avail. The siding is an actual siding profile - Parch Siding - and not a typical texture.

I used to get the same results (the discordant wavy lines) when I accidently created a siding texture with a small scale. But this is the first I have seen this.


? ?

[Dwight]

experiment with a larger render.

What anti-alias setting?

[Thomas Holm]

gpowless wrote:
I tried altering both to no avail. The siding is an actual siding profile - Parch Siding - and not a typical texture.

I used to get the same results (the discordant wavy lines) when I accidently created a siding texture with a small scale. But this is the first I have seen this.

(edited)
Well, I think that confirms it's a resolution issue. On my screen, in the pre-view image (the one you see below your post before you click on it to enlarge) this issue is much more pronounced. It's reduced in the enlarged image (the one you posted) and would probably dissappear in a four times as big image (that is, for example go from pixel dimension 1000x2000 to 2000x4000).

However, that may be a very impractical solution, increasing render times intolerably etc. Another way to deal with this issue would be to reduce the sharp shadows the boards cast. A Dwightish "undersun" would probably make them greyer and letting the antialiasing engine do it's job more efficiently (it's coded not to reduce very sharp contrasts, because if it did, it would in effect be an unsharpen filter instead). Also, this would make the soffits more realistic.

If this doesn't work, experiment with other lighting settings, moving around the main shadow-casting light source, increasing fill light etc. Read Dwight's book!

[Dwight]

What does the inventor say?

[gpowless]

Thanks to those who offered suggestions.

I tried a couple of those ideas i.e. underlighting but it didn't work. Instead I experimented again with the light and sun angles and was able to improve the rendering quite a bit by raising the sun altitude to 60 deg and making it perpendicular to the camera angle.

I would have like to uplight a little to accent the cornice but unfortunately the siding became too washed out.

Thanks again,

Gregg

[Thomas Holm]

Well, the front facade looks much better now. With the wider shadows on the siding, the antialiasing enginge understands that these are not lines that should be kept sharp at all cost.

The "undersun" should work if you make it weak enough, but this is OK.

But you have to decide what time of day it is. Now, it's full daylight on the front siding, but night to the right. And the porch lights are ablaze.

Either turn off the interior and porch lights and add a non-shadowcasting fill light (a weak "sun") from the right, or weaken the main "sun" to make it look more like moonlight.

Dwight's book has a lot to give about lighting! It's not just about LightWorks, it's about how light works! Useful with any rendering application.