Dark line in filter

Hi,
Does anyone know why this filter has a dark vertical line running down the center?

Thanks,
Ron

BTW, don't laugh - it's a work in progress.

wip.ffxml

nah it's there. you've got me, i have no idea what's causing that. sorry!

i got it, the artifact is caused by using the same perlin for the horizontal as for the diagonal. create a second perlin with a different vatiation and plug that in to the offset to make the diagonal lines, and that fixes the problem.

ok, garbanzo is on the right track, but if you duplicate the exact settings as ron has in that preset, the line is still there. and, that's true whether you re-map garbanzo's new perlin like the other perlin or not.

the problem isnt the perlin; it's the profile gradient. eliminate it. i did what garbanzo did and introduced a new perlin but i bypassed the prof grad completely; just took it out of the equation. i've found oddities like this before with a prof grad as one of the main seeds of a filter. and whether i re-map this new perlin to the same settings as the other or not, the problem is gone. and, that again points to the prof grad as the culprit here.

the down side to my fix is that the look is slightly changed.

wip rev 5a.ffxml

ah, ok. that works and is closer to his original. i also checked it with re-mapping the perlin to the same settings as his perlin. that works too! cool beans and well done, garbanzo!

Wow: I walk away for a bit and when I get back all my problems have been solved for me. Maybe I should have asked how I change this filter so it will be HU. Thanks to everyone for taking time to look at it.

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uuk wrote: there's no sign of a Dark line

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StevieJ wrote: I think you are talking about the darker/grey ones at the bottom

Sorry about that uuk and StevieJ; I should have done a better job of setting up the question. I guess I played around with it enough that it started to look like a dent on a hood to me.

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garbanzo wrote: i got it, the artifact is caused by using the same perlin for the horizontal as for the diagonal

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StevieJ wrote: I have run ito this many times.....just have to offset the variations

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Kraellin wrote: it's the profile gradient. eliminate it

You guys nailed it; pretty hoopy piece of diagnostics. For some reason I kept thinking the problem laid with the way I was using threshold.

Thanks to everyone!!