diff --git a/meshroom/nodes/aliceVision/FeatureMatching.py b/meshroom/nodes/aliceVision/FeatureMatching.py
index bbcab8bc3b..8cbe2578e8 100644
--- a/meshroom/nodes/aliceVision/FeatureMatching.py
+++ b/meshroom/nodes/aliceVision/FeatureMatching.py
@@ -64,7 +64,7 @@ class FeatureMatching(desc.AVCommandLineNode):
             label="Describer Types",
             description="Describer types used to describe an image.",
             value=["dspsift"],
-            values=["sift", "sift_float", "sift_upright", "dspsift", "akaze", "akaze_liop", "akaze_mldb", "cctag3", "cctag4", "sift_ocv", "akaze_ocv", "tag16h5"],
+            values=["sift", "sift_float", "sift_upright", "dspsift", "akaze", "akaze_liop", "akaze_mldb", "cctag3", "cctag4", "sift_ocv", "akaze_ocv", "tag16h5", "unknown"],
             exclusive=False,
             uid=[0],
             joinChar=",",
diff --git a/meshroom/nodes/aliceVision/StructureFromMotion.py b/meshroom/nodes/aliceVision/StructureFromMotion.py
index 77a4a6bd76..2f6529b386 100644
--- a/meshroom/nodes/aliceVision/StructureFromMotion.py
+++ b/meshroom/nodes/aliceVision/StructureFromMotion.py
@@ -98,7 +98,7 @@ class StructureFromMotion(desc.AVCommandLineNode):
             label="Describer Types",
             description="Describer types used to describe an image.",
             value=["dspsift"],
-            values=["sift", "sift_float", "sift_upright", "dspsift", "akaze", "akaze_liop", "akaze_mldb", "cctag3", "cctag4", "sift_ocv", "akaze_ocv", "tag16h5"],
+            values=["sift", "sift_float", "sift_upright", "dspsift", "akaze", "akaze_liop", "akaze_mldb", "cctag3", "cctag4", "sift_ocv", "akaze_ocv", "tag16h5", "unknown"],
             exclusive=False,
             uid=[0],
             joinChar=",",
diff --git a/meshroom/submitters/rippleSubmitter.py b/meshroom/submitters/rippleSubmitter.py
index d524ce7d55..69ad679bbc 100644
--- a/meshroom/submitters/rippleSubmitter.py
+++ b/meshroom/submitters/rippleSubmitter.py
@@ -44,6 +44,9 @@ def createTask(self, meshroomFile, node, parents):
             "INTENSIVE":",gpu16G"
         }
 
+        #Specify some constraints
+        requirements = "!\"rs*\",@.mem>25{gpu}".format(gpu=gpudict[node.nodeDesc.gpu.name])
+        
         #decide if we need multiple slots
         minProcessors = 1
         maxProcessors = 1
@@ -52,12 +55,10 @@ def createTask(self, meshroomFile, node, parents):
             minProcessors = 2
             #if more than 2 are available without waiting, use 3 or 4
             maxProcessors = 4
+            requirements = requirements + ",!\"rr*\""
         elif Level.NORMAL in (node.nodeDesc.ram, node.nodeDesc.cpu):
             #if 2 are available, otherwise 1
             maxProcessors = 2
-        
-        #Specify some constraints
-        requirements = "!\"rs*\",@.mem>25{gpu}".format(gpu=gpudict[node.nodeDesc.gpu.name])
 
         #specify which node to wait before launching the current one
         waitsFor = []