I'm interested in making this top transparent. I thought that, since it fits close to the body, all I needed to do was change the alpha channel to gray. Instead of becoming see-thru the color becomes washed out. Since the entire dress has backfaces I've tried leaving their alpha pure white as well as gray but the results are always the same. The pink top in the pic is set to opaque and everything looks correct. The red version has the alpha set to almost completely transparent. The transparency show up fine in TSRW, but the in-game screenshot looks like carp. Is this top a candidate for the SimHairSimple change or have I made another noob mistake? The swimsuit under the dress is Sims4Me's (BloomsBase?) accessory stuff.

If you leave the shader set to SimSkin, making the alpha gray will make the dress texture translucent with the skintone texture layered underneath and the mesh still opaque. This may be what's making the color look washed out. If you change the dress mesh to SimHairSimple, the mesh itself should be translucent with the body mesh visible through it.

Transparency will probably always wash out the color somewhat, but you may be able to brighten the preset colors to compensate.

I'm going to set the shader to SimHairSimple then. It sounds like what I'm going to need for my current project anyway. The problem with this dress isn't just the washed out color though. I've come to expect that from other things I've made see-thru by just changing the alpha channel. With this item though, changing the alpha doesn't make the item show any transparency at all. It just picks up a sickly gray overtone. The red version is almost invisible in TSRW. Because of this I was wondering if the backfaces are having some effect. I've never tried to make a transparent item with any backfaces at all, much less the entire mesh.
I'd like to make this with both the transparent and opaque options. If I modify the shader to SimHairSimple, won't I lose the opaque version?

Yes, since it's a mesh modification it'll have to be a separate version.

After fussing around with the grayscale levels in the alpha channel, I was able to get some awesome results with a pareo I just finished. It is possible to get a fully opaque preset on a transparent mesh by leaving the alpha channel pure white. The shadows do get changed when the shader is changed to CasSimHairSimple, but for the items I've used it on, the missing shadows look more natural.

You're right - I didn't think of making the alpha pure white. This should also be a way of making a layer with complex edges, like lace, without needing a complex mesh.

Already done Cmar! I didn't make an edge per se, but lace is entirely doable. The alpha channel was printed with the lace pattern in white and the more transparent areas in a light gray. I also edited the mask to match the pattern. With 2 color channels all kinds of cool combinations are possible. Making an area completely invisible is a little TOO easy. I thought I was doing something wrong when I first started messing with this because my mesh would never show up. Turns out I was using too dark a gray in the alpha channel. It's much more sensitive to shading than the usual way to make transparency on skin tight stuff.

Looking really good, too!

Did anyone do this with blender?
I can't seem to get it to work...
I think the export plugin isn't ready :-/

Hello.
Not sure that anyone would see that :O but decided to post my question here nonetheless as I didn't want to create a new thread.
I was wondering if this tutorial works also for creating clothes with lace parts and if yes, I'd really appreciate any tips - still quite the newbie ))

Thanks in advance

As long as you use the Simhair shader everything will basically work if you want to create transparent meshes.