How to set global z range for gizmo image plot?

I am guessing that you are using Gizmo Image objects and not Surface objects that are z-slices from some volumetric data.  If that is the case, each Gizmo Image uses a completely independent range for its colorscale that only depends on the range of z-values in the image data.  

One solution that I can think of is for you to create each one of the desired images as an RGB image that has the appropriate colorscale range and then create Gizmo Image objects from the RGB images.  You can create RGB images by displaying the image, modifying its colorscale range saving to disk and then reloading.  You can also do so programmatically.  Here is an example:

•Make/n=(100,200) ddd=20*p/100,eee=20+20*p/100,fff=40+20*p/100

•image2RGB(ddd,0,60)
•image2RGB(eee,0,60)
•image2RGB(fff,0,60)

Function image2RGB(Wave imageData2D,variable globalMin,variable globalMax)

	ColorTab2Wave YellowHot256
	Wave M_Colors
	MatrixOP/O M_Colors=uInt8(M_Colors/256)

	Variable N=DimSize(M_colors,0)
	Variable rows=DimSize(imageData2D,0)
	Variable cols=DimSize(imageData2D,1)
	Variable pixels=rows*cols
	Variable factor=(N-1)/(globalMax-globalMin)
	Variable row,col,index
	String name=nameofwave(imageData2d)+"_RGB"
	Make/O/N=(rows,cols,3)/u/b $name
	Wave myRGBImagewave=$name
	for(row=0;row<rows;row+=1)
		for(col=0;col<cols;col+=1)
			index=trunc(factor*(imageData2D[row][col]-globalMin))
			myRGBImagewave[row][col][0]=M_Colors[index][0]
			myRGBImagewave[row][col][1]=M_Colors[index][1]
			myRGBImagewave[row][col][2]=M_Colors[index][2]
		endfor
	endfor
End

The Gizmo recreation macro is:

Window gizmo0() : GizmoPlot
	PauseUpdate; Silent 1		// building window...
	// Building Gizmo 9 window...
	NewGizmo/W=(26.25,50,412.5,395)
	ModifyGizmo startRecMacro=1001
	ModifyGizmo scalingOption=63
	AppendToGizmo Axes=boxAxes,name=axes0
	ModifyGizmo ModifyObject=axes0,objectType=Axes,property={-1,axisScalingMode,1}
	ModifyGizmo modifyObject=axes0,objectType=Axes,property={-1,Clipped,0}
	AppendToGizmo Image=root:ddd_RGB,name=image0
	ModifyGizmo ModifyObject=image0,objectType=image,property={ srcType,2}
	ModifyGizmo ModifyObject=image0,objectType=image,property={ colorType,0}
	ModifyGizmo ModifyObject=image0,objectType=image,property={ translationType,1}
	ModifyGizmo ModifyObject=image0,objectType=image,property={ translate,0,0,-1}
	ModifyGizmo ModifyObject=image0,objectType=image,property={ dataMatch,1}
	AppendToGizmo Image=root:eee_RGB,name=image1
	ModifyGizmo ModifyObject=image1,objectType=image,property={ srcType,2}
	ModifyGizmo ModifyObject=image1,objectType=image,property={ colorType,0}
	ModifyGizmo ModifyObject=image1,objectType=image,property={ translationType,1}
	ModifyGizmo ModifyObject=image1,objectType=image,property={ translate,0,0,0}
	ModifyGizmo ModifyObject=image1,objectType=image,property={ dataMatch,1}
	AppendToGizmo Image=root:fff_RGB,name=image2
	ModifyGizmo ModifyObject=image2,objectType=image,property={ srcType,2}
	ModifyGizmo ModifyObject=image2,objectType=image,property={ colorType,0}
	ModifyGizmo ModifyObject=image2,objectType=image,property={ translationType,1}
	ModifyGizmo ModifyObject=image2,objectType=image,property={ translate,0,0,1}
	ModifyGizmo ModifyObject=image2,objectType=image,property={ dataMatch,1}
	ModifyGizmo setDisplayList=0, object=axes0
	ModifyGizmo setDisplayList=1, object=image0
	ModifyGizmo setDisplayList=2, object=image1
	ModifyGizmo setDisplayList=3, object=image2
	ModifyGizmo autoscaling=1
	ModifyGizmo currentGroupObject=""
	ModifyGizmo showInfo
	ModifyGizmo infoWindow={555,11,1380,313}
	ModifyGizmo showAxisCue=1
	ModifyGizmo SETQUATERNION={0.575342,-0.001129,-0.150273,0.803990}
	ModifyGizmo endRecMacro
EndMacro

I hope this helps,

AG

Thank you for your help!