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I'm trying to import images as planes to make a diorama in blender, and with Cycles, the images have this strange artifact where you can't see through some of them: The black part in the image below. Right now i have them all as blend mode: Alpha blend, and shadow mode: alpha hashed. Does anybody know what could be going on? enter image description here

Below is what the same setup looks like in Eevee with a reflection plane, was wanting to use cycles to try to make the reflection they're standing on like water and add some ripples and things. Any idea what could be happening? Thank you!!! enter image description here

Capsule
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    Alpha Blend and Alpha Hashed are only used for Eevee, those settings don't matter for Cycles. Is the above Cycles screenshot showing the Rendered View or is it Material Preview? Because alpha transparency is shown in black in Cycles when you're in Material Preview, it's only transparent in Rendered View. If this is Rendered View then you maybe have to go to Render Settings > Light Paths > Max Bounces and set a higher value for Transparency (or even for Transmission). Then you maybe need to set the Total bounces higher as well. – Gordon Brinkmann Apr 22 '21 at 21:06
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    You got it! The transparency options in the render settings is what did it. Thank you so much!! Blender is great, but there's so many settings that I have no idea where to even start looking when something goes wrong. Thank you so much for your help!!! – Capsule Apr 22 '21 at 21:25
  • I've entered this as an answer with even further explanations. Maybe this will help others as well. – Gordon Brinkmann Apr 23 '21 at 10:51
  • @batFINGER Although that answer has lots of upvotes, the respondent mixes up Transparency and Transmission bounces, especially because he says that from Blender 2.8* upwards you should increase the Transmission bounces. But that's wrong, this wouldn't help in this case. Also he doesn't give hints on the dependencies between Total and Transmission bounces. In his screenshot they both have a value of 12, which is okay. But if 12 wasn't enough, increasing only the Transmission bounces won't make a difference - whereas Transparency (which is what's needed) would work when increased. – Gordon Brinkmann Apr 23 '21 at 12:35
  • Suggest making this comment on potential dupe answer, so Drudge nka @Ascalon can also make the required Transmission --> Transparency edit – batFINGER Apr 23 '21 at 12:44
  • Yes, I did. I hope this not to be closed as duplicate, because it wasn't clear to me if the screenshot was Material Preview or Rendered View, and there is a different possible solution for the black area if it was only preview as I say in my answer. – Gordon Brinkmann Apr 23 '21 at 12:58

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Alpha Blend and Alpha Hashed are only used for Eevee, those settings don't matter for Cycles.

In Cycles, Alpha transparency is shown different in Rendered View and Material Preview. Alpha transparency (like from an alpha channel or the Transparent Shader) is shown in black for Alpha = 0 in Material Preview or not shown as transparent at all when Alpha > 0, it's only transparent in Rendered View.

When the transparent parts are shown black in Rendered View then you maybe have to go to Render Settings > Light Paths > Max Bounces and set a higher value for Transparency, this is for materials with transparency set in the Alpha channel of the Principled BSDF for example or where the textures have Alpha maps to mix in with a Transparent Shader or volumes like a Smoke Domain etc. The Transparency Bounces can be set independently without having to change other bounce values.

If you instead have a Glass BSDF or other transmissive material like using the Transmission channel in the Principled BSDF, then you have to set a higher bounce value for Transmission in Light Paths, and maybe even in Total if it's too low. Because unlike Transparency, the Transmission (and other) bounces are dependent on the Total value. Setting Transmission to 16 with a Total set to 4 will result in having Transmission clipped to 4 as well, so the Total value should cover the highest value of the individual bounces (except for Transparency).

bounce settings

PS: I've included the Smoke Domain as example for Transparency bounces because, apart from having a bounce value for Volume here as well, low transparency bounces are what sometimes causes smoke to have ugly black artifacts, which I've seen a lot in smoke tutorials but tutors tend to call it a bug or clipping by the Adaptive Domain.

Gordon Brinkmann
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