[Dieter]

Hi,

I started this year with MaxwellRender and learned al lot by reading this forum. But there is one thing I´m testing and testing and cannot find a result. I searched the forum for soft alpha, gradient texture, transparency etc. but could not find the reason, why my soft texture results in a 1Bit render. I tried somethig with cinema-materials (alpha/transparency) and mxm (transmittance / Layer-weights), but the result is always the same. Sorry, I´m not so familiar with mxed. Could you please help me, what I´m doing wrong?
Thanks for your time.
Dieter

[tom]

http://www.maxwellrender.com/forum/view ... hp?t=16232

[Dieter]

Thanks Tom,

but if I use a transmittance map for the second BSDF-Layer,
like the tutorial shows, i get a hard edge again.
I found out, that I may not use a texture for the
transmittance, only for the weightmap.
Transmittance is just RGB 255.
Whatever I did there, most important is, it works like I wanted.

Thanks again,
Dieter

[Mihai]

In the transmittance channel you can only use clipmaps, that is maps which have no grey values, only black or white. So you get a totally opaque/invisible behavior.

Your approach is correct if you want a gradual transparency and by setting the transmittance in one of the BSDFs to 255 you are effectively making it completely transparent, that's why it works.

[tom]

Dieter, sorry I didn't notice that mistake in that tutorial. You're right and found the correct way. But maybe that's better now you know how and why.

[Dieter]

Thank you Mihai and Tom,

yes, thats the best way to become closer with the material editor.
By the way, I wanted this plane to darken the edges of my
cinema4d-area-lights. I know I could use an emitter-mxm,
but it´s faster for me to change the light-energy in cinema
for the final (large!) render without multilight, than to change
the emitter-mxm.

Dieter

[smvwhite]

I was surprised to find your render output Dieter, having believed all this time that Maxwell Render was unable to provide transparency as a gradient (gradually increasing white through grey to black).

I have tried the same settings with a hair map (hoping to also use Maxwell for rendering characters) only to find the following output (see image).

I am kind of getting the desired effect (hair is gradually faded out), however if this behaved like your map Dieter, I would not be seeing the grey polygons of the planes to which the hair is mapped.

I have resaved the map to png in case this was causing the problem - still the same output as shown in the image.

I have varied the weight map percentages (cannot see your values Dieter on your images), but this does not seem to alter the output at all.

If my settings are exactly taken from your screen captures, does anyone have any ideas what is amiss? Apart from me (lol)?

I know of the threshold trick in Photoshop but was hoping to get the transparency happening without having a hard edge to the hair groups.

[KurtS]

make TWO layers with weightmaps. One layer for the hair, and one layer invisible (ghost layer). Use the same weightmap for both layer, only inverted for one of the layers.

[smvwhite]

Thanks for the reply KurtS - I think this is what I have done - unless I have missed something.

BTW - I love visiting your test lab. Amazing work!!

edit: resized image

[Fernando Tella]

Transmittance in the second layer should be full white to make a ghost layer. Check to see if it is 255,255,255, cause I bet it's not.

[smvwhite]

Hi Fernando,

Yep. You bet correctly. I never knew this had to be white - still learning in Maxwell. Now I get a render failure error I wasn't getting before so I will need to check through the settings again - some texture problem despite loading all the textures.

Will do a final post when I see it working. Thanks for your help.

[Fernando Tella]

Welcome!

Nd 1 and white transmittance make a ghost layer.

[smvwhite]

Yes. The hair transparency is a success.

So THAT'S what a ghost layer is. ND1 and 255, 255, 255, eh?

Unfortunately, this self-taught thing is slow going but thanks to helpful people such as you Fernando (and KurtS) I might just one day get good on Maxwell ( heh heh)

edit: Thank you Dieter for this thread.

I'd love to be able to do half the stuff I read about and see on these forums (without dead-ends and needing help, I mean).

1000 Thanks again - this one has had me thinking for a while now.

[Dieter]

Hi smvwhite,

sorry, couldn´t answer, just back from holiday.
Nice to read, that there is a happy end
and that I´m not alone with learning basics.

Good luck,
Dieter