diff --git a/viscy/light/engine.py b/viscy/light/engine.py
index f3886147..08b85319 100644
--- a/viscy/light/engine.py
+++ b/viscy/light/engine.py
@@ -29,7 +29,7 @@
 from viscy.evaluation.evaluation_metrics import mean_average_precision, ms_ssim_25d
 from viscy.unet.networks.fcmae import FullyConvolutionalMAE
 from viscy.unet.networks.Unet2D import Unet2d
-from viscy.unet.networks.Unet21D import Unet21d
+from viscy.unet.networks.Unet22D import Unet22d
 from viscy.unet.networks.Unet25D import Unet25d
 
 try:
@@ -40,9 +40,7 @@
 
 _UNET_ARCHITECTURE = {
     "2D": Unet2d,
-    "2.1D": Unet21d,
-    # same class with out_stack_depth > 1
-    "2.2D": Unet21d,
+    "2.2D": Unet22d,
     "2.5D": Unet25d,
     "fcmae": FullyConvolutionalMAE,
 }
@@ -139,8 +137,6 @@ def __init__(
             raise ValueError(
                 f"Architecture {architecture} not in {_UNET_ARCHITECTURE.keys()}"
             )
-        if architecture == "2.2D":
-            model_config["out_stack_depth"] = model_config["in_stack_depth"]
         self.model = net_class(**model_config)
         # TODO: handle num_outputs in metrics
         # self.out_channels = self.model.terminal_block.out_filters
diff --git a/viscy/scripts/network_diagram.py b/viscy/scripts/network_diagram.py
index 419d69a4..dc436cdf 100644
--- a/viscy/scripts/network_diagram.py
+++ b/viscy/scripts/network_diagram.py
@@ -44,29 +44,30 @@
 graph25d
 
 # %%
-# 2.1D UNet without upsampling in Z.
+# 3D->2D
 model = VSUNet(
-    architecture="2.1D",
+    architecture="2.2D",
     model_config={
         "in_channels": 2,
-        "out_channels": 1,
-        "in_stack_depth": 9,
+        "out_channels": 3,
+        "in_stack_depth": 5,
+        "out_stack_depth": 1,
         "backbone": "convnextv2_tiny",
-        "stem_kernel_size": (3, 1, 1),
         "decoder_mode": "pixelshuffle",
+        "stem_kernel_size": (5, 4, 4),
     },
 )
 
 model_graph = draw_graph(
     model,
     model.example_input_array,
-    graph_name="2.1D UNet",
+    graph_name="2.2D UNet",
     roll=True,
     depth=3,
 )
 
-graph21d = model_graph.visual_graph
-graph21d
+model_graph.visual_graph
+
 # %%
 # 2.1D UNet with upsampling in Z.
 model = VSUNet(
diff --git a/viscy/unet/networks/Unet21D.py b/viscy/unet/networks/Unet22D.py
similarity index 90%
rename from viscy/unet/networks/Unet21D.py
rename to viscy/unet/networks/Unet22D.py
index c4320240..a215ff0e 100644
--- a/viscy/unet/networks/Unet21D.py
+++ b/viscy/unet/networks/Unet22D.py
@@ -64,7 +64,7 @@ def _get_convnext_stage(
     return stage
 
 
-class Conv21dStem(nn.Module):
+class Conv22dStem(nn.Module):
     """Stem for 2.1D networks."""
 
     def __init__(
@@ -249,13 +249,13 @@ def forward(self, features: Sequence[Tensor]) -> Tensor:
         return feat
 
 
-class Unet21d(nn.Module):
+class Unet22d(nn.Module):
     def __init__(
         self,
         in_channels: int = 1,
         out_channels: int = 1,
         in_stack_depth: int = 5,
-        out_stack_depth: int = 1,
+        out_stack_depth: int = None,
         backbone: str = "convnextv2_tiny",
         pretrained: bool = False,
         stem_kernel_size: tuple[int, int, int] = (5, 4, 4),
@@ -273,18 +273,8 @@ def __init__(
                 f"Input stack depth {in_stack_depth} is not divisible "
                 f"by stem kernel depth {stem_kernel_size[0]}."
             )
-        if not (in_stack_depth == out_stack_depth or out_stack_depth == 1):
-            raise ValueError(
-                "`out_stack_depth` must be either 1 or "
-                f"the same as `input_stack_depth` ({in_stack_depth}), "
-                f"but got {out_stack_depth}."
-            )
-        if not (in_stack_depth == out_stack_depth or out_stack_depth == 1):
-            raise ValueError(
-                "`out_stack_depth` must be either 1 or "
-                f"the same as `input_stack_depth` ({in_stack_depth}), "
-                f"but got {out_stack_depth}."
-            )
+        if out_stack_depth is None:
+            out_stack_depth = in_stack_depth
         multi_scale_encoder = timm.create_model(
             backbone,
             pretrained=pretrained,
@@ -295,7 +285,7 @@ def __init__(
         # replace first convolution layer with a projection tokenizer
         multi_scale_encoder.stem_0 = nn.Identity()
         self.encoder_stages = multi_scale_encoder
-        self.stem = Conv21dStem(
+        self.stem = Conv22dStem(
             in_channels, num_channels[0], stem_kernel_size, in_stack_depth
         )
         decoder_channels = num_channels
@@ -311,16 +301,13 @@ def __init__(
             strides=[2] * (len(num_channels) - 1) + [stem_kernel_size[-1]],
             upsample_pre_conv="default" if decoder_upsample_pre_conv else None,
         )
-        if out_stack_depth == 1:
-            self.head = UnsqueezeHead()
-        else:
-            self.head = PixelToVoxelHead(
-                decoder_channels[-1],
-                out_channels,
-                out_stack_depth,
-                head_expansion_ratio,
-                pool=head_pool,
-            )
+        self.head = PixelToVoxelHead(
+            decoder_channels[-1],
+            out_channels,
+            out_stack_depth,
+            head_expansion_ratio,
+            pool=head_pool,
+        )
         self.out_stack_depth = out_stack_depth
 
     @property
diff --git a/viscy/unet/networks/fcmae.py b/viscy/unet/networks/fcmae.py
index 97771365..51345906 100644
--- a/viscy/unet/networks/fcmae.py
+++ b/viscy/unet/networks/fcmae.py
@@ -18,7 +18,7 @@
 )
 from torch import BoolTensor, Size, Tensor, nn
 
-from viscy.unet.networks.Unet21D import PixelToVoxelHead, Unet2dDecoder, UnsqueezeHead
+from viscy.unet.networks.Unet22D import PixelToVoxelHead, Unet2dDecoder, UnsqueezeHead
 
 
 def _init_weights(module: nn.Module) -> None: