diff --git a/include/nbl/ext/MitsubaLoader/SContext.h b/include/nbl/ext/MitsubaLoader/SContext.h
index 4380d9ddf1..334f9bca52 100644
--- a/include/nbl/ext/MitsubaLoader/SContext.h
+++ b/include/nbl/ext/MitsubaLoader/SContext.h
@@ -61,7 +61,7 @@ namespace MitsubaLoader
 			return imageCacheKey + "?view";
 		}
 
-		static std::string derivMapCacheKey(const CElementBSDF::BumpMap& _bump)
+		static std::string derivMapCacheKey(const CElementTexture* bitmap, bool wasNormal)
 		{
 			using namespace std::string_literals;
 			static const char* wrap[5]
@@ -73,18 +73,17 @@ namespace MitsubaLoader
 				"?one"
 			};
 
-			const auto* bitmap = _bump.texture;
 			std::string key = bitmap->bitmap.filename.svalue + "?deriv"s;
-			key += _bump.wasNormal ? "n"s:"h"s;
+			key += wasNormal ? "?n"s:"?h"s;
 			key += wrap[bitmap->bitmap.wrapModeU];
 			key += wrap[bitmap->bitmap.wrapModeV];
 
 			return key;
 		}
 
-		static std::string derivMapViewCacheKey(const CElementBSDF::BumpMap& _bump)
+		static std::string derivMapViewCacheKey(const CElementTexture* bitmap, bool wasNormal)
 		{
-			return imageViewCacheKey(derivMapCacheKey(_bump));
+			return imageViewCacheKey(derivMapCacheKey(bitmap,wasNormal));
 		}
 
 		static std::string blendWeightViewCacheKey(const CElementTexture* bitmap)
diff --git a/src/nbl/ext/MitsubaLoader/CMitsubaLoader.cpp b/src/nbl/ext/MitsubaLoader/CMitsubaLoader.cpp
index cb2a078fa6..942e6e4278 100644
--- a/src/nbl/ext/MitsubaLoader/CMitsubaLoader.cpp
+++ b/src/nbl/ext/MitsubaLoader/CMitsubaLoader.cpp
@@ -1271,12 +1271,13 @@ auto CMitsubaLoader::genBSDFtreeTraversal(SContext& ctx, const CElementBSDF* _bs
 				// TODO check and restore if dummy (image and sampler)
 				auto bumpmap = std::get<0>(bm)->getCreationParameters().image;
 				auto sampler = std::get<1>(bm);
-				const std::string key = ctx.derivMapCacheKey(bsdf->bumpmap);
+				const bool wasNormal = bsdf->bumpmap.wasNormal;
+				const std::string key = ctx.derivMapCacheKey(bumpmap_element,wasNormal);
 
 				if (!getBuiltinAsset<asset::ICPUImage, asset::IAsset::ET_IMAGE>(key.c_str(), m_assetMgr))
 				{
 					// TODO: @Crisspl retrieve the normalization factor from the deriv map filter, then adjust the scale accordingly!
-					auto derivmap = createDerivMap(bumpmap.get(),sampler.get(),bsdf->bumpmap.wasNormal);
+					auto derivmap = createDerivMap(bumpmap.get(),sampler.get(),wasNormal);
 					asset::SAssetBundle imgBundle(nullptr,{ derivmap });
 					ctx.override_->insertAssetIntoCache(std::move(imgBundle), key, ctx.inner, 0u);
 					auto derivmap_view = createImageView(std::move(derivmap));
diff --git a/src/nbl/ext/MitsubaLoader/CMitsubaMaterialCompilerFrontend.cpp b/src/nbl/ext/MitsubaLoader/CMitsubaMaterialCompilerFrontend.cpp
index 06e207e366..0a9adbfb64 100644
--- a/src/nbl/ext/MitsubaLoader/CMitsubaMaterialCompilerFrontend.cpp
+++ b/src/nbl/ext/MitsubaLoader/CMitsubaMaterialCompilerFrontend.cpp
@@ -18,7 +18,7 @@ namespace MitsubaLoader
         const CElementTexture* texture = nullptr;
         float scale = 1.f;
         std::tie(texture, scale) = getTexture_common(_bump.texture);
-        std::string key = m_loaderContext->derivMapCacheKey(_bump);
+        std::string key = m_loaderContext->derivMapCacheKey(texture,_bump.wasNormal);
         if (texture->type != CElementTexture::BITMAP)
             return { nullptr, nullptr, 0.f };