diff --git a/pom.xml b/pom.xml
index 699b4af3..2927b14c 100644
--- a/pom.xml
+++ b/pom.xml
@@ -112,9 +112,9 @@ like Selective Plane Illumination Microscopy (SPIM) Data.</description>
 		<imglib2-algorithm.version>0.16.0</imglib2-algorithm.version>
 		<imglib2-roi.version>0.15.1</imglib2-roi.version>
 		<n5-imglib2.version>7.0.2</n5-imglib2.version>
-		<bigdataviewer-core.version>10.6.1</bigdataviewer-core.version>
 		<bigdataviewer-vistools.version>1.0.0-beta-36</bigdataviewer-vistools.version>
 -->
+		<bigdataviewer-core.version>10.6.3</bigdataviewer-core.version>
 		<spim_data.version>2.3.5</spim_data.version>
 
 		<!-- from n5-universe 
diff --git a/src/main/java/net/preibisch/mvrecon/fiji/plugin/queryXML/GenericLoadParseQueryXML.java b/src/main/java/net/preibisch/mvrecon/fiji/plugin/queryXML/GenericLoadParseQueryXML.java
index 6898c56f..b97923e1 100644
--- a/src/main/java/net/preibisch/mvrecon/fiji/plugin/queryXML/GenericLoadParseQueryXML.java
+++ b/src/main/java/net/preibisch/mvrecon/fiji/plugin/queryXML/GenericLoadParseQueryXML.java
@@ -128,6 +128,8 @@ public abstract class GenericLoadParseQueryXML<
 	protected ArrayList< ActionListener > listener = null;
 	protected GenericDialog gd = null;
 
+	protected boolean isPrefetched = false;
+
 	public Button defineNewDataset = null;
 
 	/*
@@ -149,12 +151,28 @@ public GenericLoadParseQueryXML( final X io )
 	/**
 	 * @return the SpimData object parsed from the xml
 	 */
-	public AS getData() { return data; }
+	public AS getData()
+	{
+		final URI uri = getXMLURI();
+
+		if ( !isPrefetched && ( URITools.isS3( uri ) || URITools.isGC( uri ) ) )
+		{
+			IOFunctions.println( "Setting cloud fetcher threads for '" + uri + "' to: " + URITools.cloudThreads );
+			URITools.setNumFetcherThreads( data.getSequenceDescription().getImgLoader(), URITools.cloudThreads );
+	
+			IOFunctions.println( "Prefetching with " + URITools.cloudThreads + " threads: for '" + uri + "'");
+			URITools.prefetch( data.getSequenceDescription().getImgLoader(), URITools.cloudThreads );
+
+			isPrefetched = true;
+		}
+
+		return data;
+	}
 	
 	/**
 	 * @return The location of the xml file
 	 */
-	public URI getXMLURI() { return URITools.xmlFilenameToFullPath( getData(), xmlFileName ); }
+	public URI getXMLURI() { return URITools.xmlFilenameToFullPath( data, xmlFileName ); }
 
 	/**
 	 * @return ONLY the filename, without any path
diff --git a/src/main/java/net/preibisch/mvrecon/fiji/spimdata/imgloaders/AllenOMEZarrLoader.java b/src/main/java/net/preibisch/mvrecon/fiji/spimdata/imgloaders/AllenOMEZarrLoader.java
new file mode 100644
index 00000000..037b06ce
--- /dev/null
+++ b/src/main/java/net/preibisch/mvrecon/fiji/spimdata/imgloaders/AllenOMEZarrLoader.java
@@ -0,0 +1,114 @@
+package net.preibisch.mvrecon.fiji.spimdata.imgloaders;
+
+import java.net.URI;
+import java.util.Map;
+
+import org.janelia.saalfeldlab.n5.universe.N5Factory.StorageFormat;
+
+import bdv.ViewerSetupImgLoader;
+import bdv.img.n5.N5ImageLoader;
+import bdv.img.n5.N5Properties;
+import ij.ImageJ;
+import mpicbg.spim.data.SpimDataException;
+import mpicbg.spim.data.generic.sequence.AbstractSequenceDescription;
+import mpicbg.spim.data.generic.sequence.BasicMultiResolutionSetupImgLoader;
+import mpicbg.spim.data.sequence.ViewId;
+import net.imglib2.RandomAccessibleInterval;
+import net.imglib2.cache.volatiles.CacheHints;
+import net.imglib2.img.display.imagej.ImageJFunctions;
+import net.imglib2.type.NativeType;
+import net.preibisch.mvrecon.fiji.spimdata.SpimData2;
+import net.preibisch.mvrecon.fiji.spimdata.XmlIoSpimData2;
+import net.preibisch.mvrecon.fiji.spimdata.explorer.ViewSetupExplorer;
+import util.URITools;
+
+public class AllenOMEZarrLoader extends N5ImageLoader
+{
+	private final AbstractSequenceDescription< ?, ?, ? > sequenceDescription;
+
+	private final Map< ViewId, String > viewIdToPath;
+
+	private final String bucket, folder;
+
+	public AllenOMEZarrLoader(
+			final URI n5URI,
+			final String bucket,
+			final String folder,
+			final AbstractSequenceDescription< ?, ?, ? > sequenceDescription,
+			final Map< ViewId, String > viewIdToPath )
+	{
+		super( URITools.instantiateN5Reader( StorageFormat.ZARR, n5URI ), n5URI, sequenceDescription );
+		this.sequenceDescription = sequenceDescription;
+
+		this.bucket = bucket;
+		this.folder = folder;
+
+		this.viewIdToPath = viewIdToPath;
+	}
+
+	public Map< ViewId, String > getViewIdToPath()
+	{
+		return viewIdToPath;
+	}
+
+	public String getBucket()
+	{
+		return bucket;
+	}
+
+	public String getFolder()
+	{
+		return folder;
+	}
+
+	@Override
+	protected N5Properties createN5PropertiesInstance()
+	{
+		return new AllenOMEZarrProperties( sequenceDescription, viewIdToPath );
+	}
+
+	@Override
+	protected < T extends NativeType< T > > RandomAccessibleInterval< T > prepareCachedImage(
+			final String datasetPath,
+			final int setupId, final int timepointId, final int level,
+			final CacheHints cacheHints,
+			final T type )
+	{
+		return super.prepareCachedImage( datasetPath, setupId, 0, level, cacheHints, type ).view()
+				.slice( 4, 0 )
+				.slice( 3, 0 );
+	}
+
+	public static void main( String[] args ) throws SpimDataException
+	{
+		URI xml = URITools.toURI( "/Users/preibischs/Documents/Janelia/Projects/BigStitcher/Allen/bigstitcher_708373/708373.split.xml" );
+		//URI xml = URITools.toURI( "/Users/preibischs/Documents/Janelia/Projects/BigStitcher/Allen/bigstitcher_708373/708373.xml" );
+		//URI xml = URITools.toURI( "s3://janelia-bigstitcher-spark/Stitching/dataset.xml" );
+		//URI xml = URITools.toURI( "gs://janelia-spark-test/I2K-test/dataset.xml" );
+		//URI xml = URITools.toURI( "/Users/preibischs/SparkTest/IP/dataset.xml" );
+
+		XmlIoSpimData2 io = new XmlIoSpimData2();
+		SpimData2 data = io.load( xml );
+
+		System.out.println( "Setting cloud fetcher threads to: " + URITools.cloudThreads );
+		URITools.setNumFetcherThreads( data.getSequenceDescription().getImgLoader(), URITools.cloudThreads );
+
+		System.out.println( "Prefetching with threads: " + URITools.cloudThreads );
+		URITools.prefetch( data.getSequenceDescription().getImgLoader(), URITools.cloudThreads );
+
+		//imgL.setNumFetcherThreads( cloudThreads );
+		ViewerSetupImgLoader sil = (ViewerSetupImgLoader)data.getSequenceDescription().getImgLoader().getSetupImgLoader( 0 );
+
+		final int tp = data.getSequenceDescription().getTimePoints().getTimePointsOrdered().get( 0 ).getId();
+
+		//RandomAccessibleInterval img = sil.getImage( tp, sil.getMipmapResolutions().length - 1 );
+		RandomAccessibleInterval vol = sil.getVolatileImage( tp, ((BasicMultiResolutionSetupImgLoader)sil).getMipmapResolutions().length - 1 );
+
+		new ImageJ();
+		//ImageJFunctions.show( img );
+		ImageJFunctions.show( vol );
+
+		final ViewSetupExplorer< SpimData2 > explorer = new ViewSetupExplorer<>( data, xml, io );
+		explorer.getFrame().toFront();
+	}
+}
diff --git a/src/main/java/net/preibisch/mvrecon/fiji/spimdata/imgloaders/AllenOMEZarrProperties.java b/src/main/java/net/preibisch/mvrecon/fiji/spimdata/imgloaders/AllenOMEZarrProperties.java
new file mode 100644
index 00000000..e878f1e5
--- /dev/null
+++ b/src/main/java/net/preibisch/mvrecon/fiji/spimdata/imgloaders/AllenOMEZarrProperties.java
@@ -0,0 +1,132 @@
+package net.preibisch.mvrecon.fiji.spimdata.imgloaders;
+
+import java.util.Arrays;
+import java.util.Map;
+
+import org.janelia.saalfeldlab.n5.DataType;
+import org.janelia.saalfeldlab.n5.N5Reader;
+import org.janelia.saalfeldlab.n5.universe.metadata.ome.ngff.v04.OmeNgffMultiScaleMetadata;
+import org.janelia.saalfeldlab.n5.universe.metadata.ome.ngff.v04.OmeNgffMultiScaleMetadata.OmeNgffDataset;
+import org.janelia.saalfeldlab.n5.universe.metadata.ome.ngff.v04.coordinateTransformations.CoordinateTransformation;
+import org.janelia.saalfeldlab.n5.universe.metadata.ome.ngff.v04.coordinateTransformations.ScaleCoordinateTransformation;
+
+import bdv.img.n5.N5Properties;
+import mpicbg.spim.data.generic.sequence.AbstractSequenceDescription;
+import mpicbg.spim.data.sequence.TimePoint;
+import mpicbg.spim.data.sequence.ViewId;
+
+public class AllenOMEZarrProperties implements N5Properties
+{
+	private final AbstractSequenceDescription< ?, ?, ? > sequenceDescription;
+
+	private final Map< ViewId, String > viewIdToPath;
+
+	public AllenOMEZarrProperties(
+			final AbstractSequenceDescription< ?, ?, ? > sequenceDescription,
+			final Map< ViewId, String > viewIdToPath )
+	{
+		this.sequenceDescription = sequenceDescription;
+		this.viewIdToPath = viewIdToPath;
+	}
+
+	private String getPath( final int setupId, final int timepointId )
+	{
+		return viewIdToPath.get( new ViewId( timepointId, setupId ) );
+	}
+
+	@Override
+	public String getDatasetPath( final int setupId, final int timepointId, final int level )
+	{
+		return String.format( getPath( setupId, timepointId )+ "/%d", level );
+	}
+
+	@Override
+	public DataType getDataType( final N5Reader n5, final int setupId )
+	{
+		return getDataType( this, n5, setupId );
+	}
+
+	@Override
+	public double[][] getMipmapResolutions( final N5Reader n5, final int setupId )
+	{
+		return getMipMapResolutions( this, n5, setupId );
+	}
+
+	@Override
+	public long[] getDimensions( final N5Reader n5, final int setupId, final int timepointId, final int level )
+	{
+		final String path = getDatasetPath( setupId, timepointId, level );
+		final long[] dimensions = n5.getDatasetAttributes( path ).getDimensions();
+		// dataset dimensions is 5D, remove the channel and time dimensions
+		return Arrays.copyOf( dimensions, 3 );
+	}
+
+	//
+	// static methods
+	//
+
+	private static int getFirstAvailableTimepointId( final AbstractSequenceDescription< ?, ?, ? > seq, final int setupId )
+	{
+		for ( final TimePoint tp : seq.getTimePoints().getTimePointsOrdered() )
+		{
+			if ( !seq.getMissingViews().getMissingViews().contains( new ViewId( tp.getId(), setupId ) ) )
+				return tp.getId();
+		}
+
+		throw new RuntimeException( "All timepoints for setupId " + setupId + " are declared missing. Stopping." );
+	}
+
+	private static DataType getDataType( final AllenOMEZarrProperties n5properties, final N5Reader n5, final int setupId )
+	{
+		final int timePointId = getFirstAvailableTimepointId( n5properties.sequenceDescription, setupId );
+		return n5.getDatasetAttributes( n5properties.getDatasetPath( setupId, timePointId, 0 ) ).getDataType();
+	}
+
+	private static double[][] getMipMapResolutions( final AllenOMEZarrProperties n5properties, final N5Reader n5, final int setupId )
+	{
+		final int timePointId = getFirstAvailableTimepointId( n5properties.sequenceDescription, setupId );
+
+		// multiresolution pyramid
+
+		//org.janelia.saalfeldlab.n5.universe.metadata.ome.ngff.v04.OmeNgffMetadata
+		// for this to work you need to register an adapter in the N5Factory class
+		// final GsonBuilder builder = new GsonBuilder().registerTypeAdapter( CoordinateTransformation.class, new CoordinateTransformationAdapter() );
+		final OmeNgffMultiScaleMetadata[] multiscales = n5.getAttribute( n5properties.getPath( setupId, timePointId ), "multiscales", OmeNgffMultiScaleMetadata[].class );
+
+		if ( multiscales == null || multiscales.length == 0 )
+			throw new RuntimeException( "Could not parse OME-ZARR multiscales object. stopping." );
+
+		if ( multiscales.length != 1 )
+			System.out.println( "This dataset has " + multiscales.length + " objects, we expected 1. Picking the first one." );
+
+		//System.out.println( "AllenOMEZarrLoader.getMipmapResolutions() for " + setupId + " using " + n5properties.getPath( setupId, timePointId ) + ": found " + multiscales[ 0 ].datasets.length + " multi-resolution levels." );
+
+		double[][] mipMapResolutions = new double[ multiscales[ 0 ].datasets.length ][ 3 ];
+		double[] firstScale = null;
+
+		for ( int i = 0; i < multiscales[ 0 ].datasets.length; ++i )
+		{
+			final OmeNgffDataset ds = multiscales[ 0 ].datasets[ i ];
+
+			for ( final CoordinateTransformation< ? > c : ds.coordinateTransformations )
+			{
+				if ( c instanceof ScaleCoordinateTransformation )
+				{
+					final ScaleCoordinateTransformation s = ( ScaleCoordinateTransformation ) c;
+
+					if ( firstScale == null )
+						firstScale = s.getScale().clone();
+
+					for ( int d = 0; d < mipMapResolutions[ i ].length; ++d )
+					{
+						mipMapResolutions[ i ][ d ] = s.getScale()[ d ] / firstScale[ d ];
+						mipMapResolutions[ i ][ d ] = Math.round(mipMapResolutions[ i ][ d ]*10000)/10000d; // round to the 5th digit
+					}
+					//System.out.println( "AllenOMEZarrLoader.getMipmapResolutions(), level " + i + ": " + Arrays.toString( s.getScale() ) + " >> " + Arrays.toString( mipMapResolutions[ i ] ) );
+				}
+			}
+		}
+
+		return mipMapResolutions;
+	}
+}
diff --git a/src/main/java/net/preibisch/mvrecon/fiji/spimdata/imgloaders/AllenOMEZarrTest.java b/src/main/java/net/preibisch/mvrecon/fiji/spimdata/imgloaders/AllenOMEZarrTest.java
new file mode 100644
index 00000000..8d6c6175
--- /dev/null
+++ b/src/main/java/net/preibisch/mvrecon/fiji/spimdata/imgloaders/AllenOMEZarrTest.java
@@ -0,0 +1,33 @@
+package net.preibisch.mvrecon.fiji.spimdata.imgloaders;
+
+import java.io.File;
+import java.util.concurrent.Future;
+
+import bdv.BigDataViewer;
+import bdv.export.ProgressWriterConsole;
+import bdv.img.n5.N5ImageLoader;
+import bdv.spimdata.SpimDataMinimal;
+import bdv.spimdata.XmlIoSpimDataMinimal;
+import bdv.tools.InitializeViewerState;
+import bdv.ui.UIUtils;
+import bdv.viewer.ViewerOptions;
+import mpicbg.spim.data.SpimDataException;
+
+public class AllenOMEZarrTest
+{
+	public static void main( String[] args ) throws SpimDataException
+	{
+		final String fn = "/Users/pietzsch/Desktop/data/Allen/704522.xml";
+
+		System.setProperty( "apple.laf.useScreenMenuBar", "true" );
+		UIUtils.installFlatLafInfos();
+
+		final SpimDataMinimal spimData = new XmlIoSpimDataMinimal().load( fn );
+		final N5ImageLoader n5ImageLoader = ( N5ImageLoader ) spimData.getSequenceDescription().getImgLoader();
+		final Future< Void > f = n5ImageLoader.prefetch( 256 );
+		n5ImageLoader.setNumFetcherThreads( 64 );
+
+		final BigDataViewer bdv = BigDataViewer.open( spimData, new File( fn ).getName(), new ProgressWriterConsole(), ViewerOptions.options() );
+		InitializeViewerState.initBrightness( 0, 1, bdv.getViewerFrame() );
+	}
+}
diff --git a/src/main/java/net/preibisch/mvrecon/fiji/spimdata/imgloaders/XmlIoAllenOMEZarrLoader.java b/src/main/java/net/preibisch/mvrecon/fiji/spimdata/imgloaders/XmlIoAllenOMEZarrLoader.java
new file mode 100644
index 00000000..cb06b14b
--- /dev/null
+++ b/src/main/java/net/preibisch/mvrecon/fiji/spimdata/imgloaders/XmlIoAllenOMEZarrLoader.java
@@ -0,0 +1,170 @@
+package net.preibisch.mvrecon.fiji.spimdata.imgloaders;
+
+/*
+ * #%L
+ * BigDataViewer core classes with minimal dependencies.
+ * %%
+ * Copyright (C) 2012 - 2024 BigDataViewer developers.
+ * %%
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ * 
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ * #L%
+ */
+
+import static mpicbg.spim.data.XmlKeys.IMGLOADER_FORMAT_ATTRIBUTE_NAME;
+
+import java.io.File;
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Map.Entry;
+
+import org.jdom2.Element;
+
+import mpicbg.spim.data.XmlHelpers;
+import mpicbg.spim.data.generic.sequence.AbstractSequenceDescription;
+import mpicbg.spim.data.generic.sequence.ImgLoaderIo;
+import mpicbg.spim.data.generic.sequence.XmlIoBasicImgLoader;
+import mpicbg.spim.data.sequence.ViewId;
+import util.URITools;
+
+@ImgLoaderIo( format = "bdv.multimg.zarr", type = AllenOMEZarrLoader.class )
+public class XmlIoAllenOMEZarrLoader implements XmlIoBasicImgLoader< AllenOMEZarrLoader >
+{
+	@Override
+	public Element toXml( final AllenOMEZarrLoader imgLoader, final File basePath )
+	{
+		return toXml( imgLoader, basePath == null ? null : basePath.toURI() );
+	}
+
+	@Override
+	public Element toXml( final AllenOMEZarrLoader imgLoader, final URI basePathURI )
+	{
+		final Element imgLoaderElement = new Element( "ImageLoader" );
+		imgLoaderElement.setAttribute( IMGLOADER_FORMAT_ATTRIBUTE_NAME, "bdv.multimg.zarr" );
+		imgLoaderElement.setAttribute( "version", "1.0" );
+
+		if ( URITools.isS3( imgLoader.getN5URI() ) || URITools.isGC( imgLoader.getN5URI() ) )
+		{
+			final Element bucketElement = new Element("s3bucket");
+			bucketElement.addContent( imgLoader.getBucket() );
+			imgLoaderElement.addContent(bucketElement);
+
+			final Element zarrElement = new Element("zarr");
+			zarrElement.setAttribute("type", "absolute");
+			zarrElement.addContent( imgLoader.getFolder() );
+			imgLoaderElement.addContent( zarrElement );
+		}
+		else
+		{
+			imgLoaderElement.addContent( XmlHelpers.pathElement( "zarr", new File( imgLoader.getN5URI() ), null));
+		}
+
+		final Element zgroupsElement = new Element( "zgroups" );
+
+		for ( final Entry<ViewId, String > entry : imgLoader.getViewIdToPath().entrySet() )
+		{
+			final Element zgroupElement = new Element("zgroup");
+			zgroupElement.setAttribute( "setup", String.valueOf( entry.getKey().getViewSetupId() ) );
+			zgroupElement.setAttribute( "timepoint", String.valueOf( entry.getKey().getTimePointId() ) );
+
+			final Element pathElement = new Element( "path" );
+			pathElement.addContent( entry.getValue() );
+			zgroupElement.addContent( pathElement );
+
+			zgroupsElement.addContent( zgroupElement );
+		}
+
+		imgLoaderElement.addContent( zgroupsElement );
+
+		return imgLoaderElement;
+	}
+
+	@Override
+	public AllenOMEZarrLoader fromXml( final Element elem, final File basePath, final AbstractSequenceDescription< ?, ?, ? > sequenceDescription )
+	{
+		return fromXml( elem, basePath.toURI(), sequenceDescription );
+	}
+
+	@Override
+	public AllenOMEZarrLoader fromXml( final Element elem, final URI basePathURI, final AbstractSequenceDescription< ?, ?, ? > sequenceDescription )
+	{
+		final Map<ViewId, String> zgroups = new HashMap<>();
+
+		final Element s3Bucket = elem.getChild( "s3bucket" );
+		final URI uri;
+		String bucket, folder;
+
+		if (s3Bucket == null)
+		{
+			uri = XmlHelpers.loadPathURI( elem, "zarr", basePathURI );
+
+			bucket = null;
+			folder = null;
+		}
+		else
+		{
+			// `File` class should not be used for uri manipulation as it replaces slashes
+			// with backslashes on Windows
+			bucket = s3Bucket.getText();
+
+			folder = elem.getChildText( "zarr" );
+
+			if ( !folder.endsWith( "/" ) )
+				folder = folder + "/";
+
+			if ( !folder.startsWith( "/" ) )
+				folder = "/" + folder;
+
+			try
+			{
+				uri = new URI( "s3", bucket, folder, null );
+			}
+			catch ( URISyntaxException e )
+			{
+				e.printStackTrace();
+				throw new RuntimeException( "Could not instantiate N5 reader for S3 bucket '" + bucket + "'." );
+			}
+
+			final Element zgroupsElem = elem.getChild( "zgroups" );
+			for ( final Element c : zgroupsElem.getChildren( "zgroup" ) )
+			{
+				final int timepointId = Integer.parseInt( c.getAttributeValue( "timepoint" ) );
+				final int setupId = Integer.parseInt( c.getAttributeValue( "setup" ) );
+				final String path = c.getChild( "path" ).getText();
+				zgroups.put( new ViewId( timepointId, setupId ), path );
+			}
+		}
+
+		try
+		{
+			System.out.println( "Opening N5 Zarr reader for '" + uri + "'" );
+
+			return new AllenOMEZarrLoader( uri, bucket, folder, sequenceDescription, zgroups );
+		}
+		catch ( Exception e )
+		{
+			e.printStackTrace();
+			return null;
+		}
+	}
+}
diff --git a/src/main/java/net/preibisch/mvrecon/fiji/spimdata/imgloaders/splitting/SplitViewerImgLoader.java b/src/main/java/net/preibisch/mvrecon/fiji/spimdata/imgloaders/splitting/SplitViewerImgLoader.java
index f38c47c4..0ce97ad2 100644
--- a/src/main/java/net/preibisch/mvrecon/fiji/spimdata/imgloaders/splitting/SplitViewerImgLoader.java
+++ b/src/main/java/net/preibisch/mvrecon/fiji/spimdata/imgloaders/splitting/SplitViewerImgLoader.java
@@ -25,11 +25,13 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.concurrent.Callable;
+import java.util.concurrent.Future;
 
 import bdv.ViewerImgLoader;
 import bdv.ViewerSetupImgLoader;
 import bdv.cache.CacheControl;
 import bdv.img.cache.VolatileGlobalCellCache;
+import bdv.img.n5.N5ImageLoader;
 import mpicbg.spim.data.generic.sequence.BasicViewSetup;
 import mpicbg.spim.data.sequence.MultiResolutionImgLoader;
 import mpicbg.spim.data.sequence.SequenceDescription;
@@ -107,6 +109,16 @@ private final synchronized SplitViewerSetupImgLoader<?,?> createNewSetupImgLoade
 		return new SplitViewerSetupImgLoader<>( Cast.unchecked( setupImgLoader ), interval );
 	}
 
+	public Future< Void > prefetch( final int parallelism )
+	{
+		if ( N5ImageLoader.class.isInstance( underlyingImgLoader ) )
+			return ( (N5ImageLoader)underlyingImgLoader).prefetch( parallelism );
+		else if ( SplitViewerImgLoader.class.isInstance( underlyingImgLoader ) )
+			return ( (SplitViewerImgLoader) underlyingImgLoader ).prefetch( parallelism );
+		else
+			return null;
+	}
+
 	@Override
 	public synchronized void setNumFetcherThreads( final int n )
 	{
diff --git a/src/main/java/util/URITools.java b/src/main/java/util/URITools.java
index ec3171ac..a377f04b 100644
--- a/src/main/java/util/URITools.java
+++ b/src/main/java/util/URITools.java
@@ -35,7 +35,6 @@
 import java.io.PrintWriter;
 import java.net.URI;
 import java.net.URISyntaxException;
-import java.nio.file.Path;
 import java.nio.file.Paths;
 import java.util.Date;
 import java.util.regex.Pattern;
@@ -51,6 +50,8 @@
 import org.janelia.saalfeldlab.n5.s3.AmazonS3Utils;
 import org.janelia.saalfeldlab.n5.universe.N5Factory;
 import org.janelia.saalfeldlab.n5.universe.N5Factory.StorageFormat;
+import org.janelia.saalfeldlab.n5.universe.metadata.ome.ngff.v04.coordinateTransformations.CoordinateTransformation;
+import org.janelia.saalfeldlab.n5.universe.metadata.ome.ngff.v04.coordinateTransformations.CoordinateTransformationAdapter;
 import org.janelia.saalfeldlab.n5.zarr.N5ZarrReader;
 import org.janelia.saalfeldlab.n5.zarr.N5ZarrWriter;
 import org.jdom2.Document;
@@ -59,13 +60,18 @@
 import org.jdom2.output.Format;
 import org.jdom2.output.XMLOutputter;
 
+import com.google.gson.GsonBuilder;
+
 import bdv.ViewerImgLoader;
+import bdv.img.n5.N5ImageLoader;
 import mpicbg.spim.data.SpimDataException;
 import mpicbg.spim.data.SpimDataIOException;
 import mpicbg.spim.data.generic.AbstractSpimData;
+import mpicbg.spim.data.generic.sequence.BasicImgLoader;
 import net.preibisch.legacy.io.IOFunctions;
 import net.preibisch.mvrecon.fiji.spimdata.SpimData2;
 import net.preibisch.mvrecon.fiji.spimdata.XmlIoSpimData2;
+import net.preibisch.mvrecon.fiji.spimdata.imgloaders.splitting.SplitViewerImgLoader;
 
 public class URITools
 {
@@ -261,10 +267,15 @@ else if ( format.equals( StorageFormat.HDF5 ))
 		{
 			N5Writer n5w;
 
+			final GsonBuilder builder = new GsonBuilder().registerTypeAdapter(
+					CoordinateTransformation.class,
+					new CoordinateTransformationAdapter() );
+
 			try
 			{
 				//System.out.println( "Trying writing with credentials ..." );
-				N5Factory factory = new N5Factory();
+				final N5Factory factory = new N5Factory();
+				factory.gsonBuilder( builder );
 				factory.s3UseCredentials();
 				n5w = factory.openWriter( format, uri );
 			}
@@ -272,11 +283,12 @@ else if ( format.equals( StorageFormat.HDF5 ))
 			{
 				System.out.println( "With credentials failed; trying anonymous ..." );
 
-				n5w = new N5Factory().openWriter( format, uri );
+				final N5Factory factory = new N5Factory();
+				factory.gsonBuilder( builder );
+				n5w = factory.openWriter( format, uri );
 			}
 
 			return n5w;
-			//return new N5Factory().openWriter( format, uri ); // cloud support, avoid dependency hell if it is a local file
 		}
 	}
 
@@ -295,21 +307,28 @@ else if ( format.equals( StorageFormat.ZARR ))
 		{
 			N5Reader n5r;
 
+			final GsonBuilder builder = new GsonBuilder().registerTypeAdapter(
+					CoordinateTransformation.class,
+					new CoordinateTransformationAdapter() );
+
 			try
 			{
 				//System.out.println( "Trying reading with credentials ..." );
-				N5Factory factory = new N5Factory();
+				final N5Factory factory = new N5Factory();
+				factory.gsonBuilder( builder );
 				factory.s3UseCredentials();
 				n5r = factory.openReader( format, uri );
 			}
 			catch ( Exception e )
 			{
-				System.out.println( "With credentials failed; trying anonymous ..." );
-				n5r = new N5Factory().openReader( format, uri );
+				System.out.println( "With credentials failed; trying anonymous with gson builder ..." );
+
+				final N5Factory factory = new N5Factory();
+				factory.gsonBuilder( builder );
+				n5r = factory.openReader( format, uri );
 			}
 
 			return n5r;
-			//return new N5Factory().openReader( format, uri ); // cloud support, avoid dependency hell if it is a local file
 		}
 	}
 
@@ -328,21 +347,27 @@ else if ( uri.toString().toLowerCase().endsWith( ".n5" ) )
 		{
 			N5Reader n5r;
 
+			final GsonBuilder builder = new GsonBuilder().registerTypeAdapter(
+					CoordinateTransformation.class,
+					new CoordinateTransformationAdapter() );
+
 			try
 			{
 				//System.out.println( "Trying reading with credentials ..." );
-				N5Factory factory = new N5Factory();
+				final N5Factory factory = new N5Factory();
+				factory.gsonBuilder( builder );
 				factory.s3UseCredentials();
 				n5r = factory.openReader( uri.toString() );
 			}
 			catch ( Exception e )
 			{
 				System.out.println( "With credentials failed; trying anonymous ..." );
-				n5r = new N5Factory().openReader( uri.toString() );
+				final N5Factory factory = new N5Factory();
+				factory.gsonBuilder( builder );
+				n5r = factory.openReader( uri.toString() );
 			}
 
 			return n5r;
-			//return new N5Factory().openReader( uri.toString() ); // cloud support, avoid dependency hell if it is a local file
 		}
 	}
 
@@ -361,22 +386,27 @@ else if ( uri.toString().toLowerCase().endsWith( ".n5" ) )
 		{
 			N5Writer n5w;
 
+			final GsonBuilder builder = new GsonBuilder().registerTypeAdapter(
+					CoordinateTransformation.class,
+					new CoordinateTransformationAdapter() );
+
 			try
 			{
 				//System.out.println( "Trying writing with credentials ..." );
-				N5Factory factory = new N5Factory();
+				final N5Factory factory = new N5Factory();
+				factory.gsonBuilder( builder );
 				factory.s3UseCredentials();
 				n5w = factory.openWriter( uri.toString() );
 			}
 			catch ( Exception e )
 			{
 				System.out.println( "Writing with credentials failed; trying anonymous writing ..." );
-				n5w = new N5Factory().openWriter( uri.toString() );
+				final N5Factory factory = new N5Factory();
+				factory.gsonBuilder( builder );
+				n5w = factory.openWriter( uri.toString() );
 			}
 
 			return n5w;
-
-			//return new N5Factory().openWriter( uri.toString() ); // cloud support, avoid dependency hell if it is a local file
 		}
 	}
 
@@ -410,9 +440,6 @@ else if ( URITools.isS3( xmlURI ) || URITools.isGC( xmlURI ) )
 
 			final SpimData2 data = io.fromXml( docRoot, xmlURI );
 
-			// more threads for cloud-based fetching
-			( (ViewerImgLoader) data.getSequenceDescription().getImgLoader() ).setNumFetcherThreads( cloudThreads );
-
 			return data;
 		}
 		else
@@ -421,6 +448,37 @@ else if ( URITools.isS3( xmlURI ) || URITools.isGC( xmlURI ) )
 		}
 	}
 
+	public static boolean setNumFetcherThreads( final BasicImgLoader loader, final int threads )
+	{
+		if ( ViewerImgLoader.class.isInstance( loader ) )
+		{
+			( (ViewerImgLoader) loader ).setNumFetcherThreads( threads );
+			return true;
+		}
+		else
+		{
+			return false;
+		}
+	}
+
+	public static boolean prefetch( final BasicImgLoader loader, final int threads )
+	{
+		if ( N5ImageLoader.class.isInstance( loader ) )
+		{
+			( ( N5ImageLoader ) loader ).prefetch( threads );
+			return true;
+		}
+		else if ( SplitViewerImgLoader.class.isInstance( loader ) )
+		{
+			if ( ( ( SplitViewerImgLoader ) loader ).prefetch( threads ) != null )
+				return true;
+			else
+				return false;
+		}
+		else
+			return false;
+	}
+
 	/**
 	 * This is an abstraction that is only required because the Google cloud and AWS KeyValueAccesses behave differently
 	 *
@@ -686,6 +744,12 @@ public static void minimalExampleTobiS3GS() throws URISyntaxException, IOExcepti
 
 	public static void main( String[] args ) throws SpimDataException, IOException, URISyntaxException
 	{
+		URI uri1 = URITools.toURI( "s3://aind-open-data/exaSPIM_708373_2024-04-02_19-49-38/SPIM.ome.zarr" );
+
+		System.out.println( uri1.getHost() );
+		System.out.println( uri1.getPath() );
+		System.exit( 0 );
+
 		minimalExampleTobiS3GS();
 
 		System.exit( 0 );