Cycles: Material full transparency, but still seeing parts of object [duplicate]

I'm trying to fade out an object by using a transparency BSDF. With Transparency set to 0 it looks like:

When turning the transparency up to 100% to get the structure opaque I get this result:

I have no idea where those dark areas are coming from. The mesh I'm using has been imported from an obj file and was originaly created with a CAD software. I have tried to recalculate surfaces and removed all doubles, but I'm still getting those dark areas.

As I want to use it in an animation I think I could turn up transparency and just before it should go 100% transparent I'd set a keyframe on Restrict Rendering in Object Explorer, but I think it still might look a bit "harsh".

Does anyone has an idea, what could be wrong?

Thank you!

marked as duplicate by gandalf3♦ cycles StackExchange.ready(function() { if (StackExchange.options.isMobile) return; $('.dupe-hammer-message-hover:not(.hover-bound)').each(function() { var$hover = $(this).addClass('hover-bound'),$msg = $hover.siblings('.dupe-hammer-message');$hover.hover( function() { $hover.showInfoMessage('', { messageElement:$msg.clone().show(), transient: false, position: { my: 'bottom left', at: 'top center', offsetTop: -7 }, dismissable: false, relativeToBody: true }); }, function() { StackExchange.helpers.removeMessages(); } ); }); }); Mar 9 '16 at 22:39

• Under your Material Panel >> Settings >> Surface... Is your Transparent Shadows option checked? – Rick Riggs Mar 9 '16 at 22:39
• Yes it is checked. Sorry, forgot to mention that. – Seb Mar 9 '16 at 22:53
• There is a mix shader with an unconected socket, could that be causing so sort of trouble, vene though the next mix node is ignoring it? – Duarte Farrajota Ramos Mar 9 '16 at 23:56
• Gandalf3 is right. His question "Black artifacts when looking through many transparent objects?", is about the same problem. Thanks for the help and sorry for the duplicate. – Seb Mar 10 '16 at 8:09