diff --git a/Project.toml b/Project.toml
index c3d99d1..101c636 100644
--- a/Project.toml
+++ b/Project.toml
@@ -33,11 +33,11 @@ ImageUtils = "0.2"
 IniFile = "0.5"
 LinearAlgebra = "1"
 LinearOperators = "2.3.3"
-LinearOperatorCollection = "1.0"
+LinearOperatorCollection = "1.2"
 MPIFiles = "0.13, 0.14, 0.15"
 ProgressMeter = "1.2"
 Reexport = "1.0"
-RegularizedLeastSquares = "0.13"
+RegularizedLeastSquares = "0.14"
 SparseArrays = "1"
 Statistics = "1"
 ThreadPools = "2.1.1"
diff --git a/src/Algorithms/SinglePatchAlgorithms/SinglePatchAlgorithm.jl b/src/Algorithms/SinglePatchAlgorithms/SinglePatchAlgorithm.jl
index 02b3ca5..0d00210 100644
--- a/src/Algorithms/SinglePatchAlgorithms/SinglePatchAlgorithm.jl
+++ b/src/Algorithms/SinglePatchAlgorithms/SinglePatchAlgorithm.jl
@@ -61,7 +61,7 @@ function process(algo::SinglePatchReconstructionAlgorithm, params::SinglePatchRe
   return gridresult(result, algo.grid, algo.sf)
 end
 
-process(algo::SinglePatchReconstructionAlgorithm, params::ChannelWeightingParameters, u) = map(real(eltype(algo.S)), process(typeof(algo), params, algo.freqs))
+process(algo::SinglePatchReconstructionAlgorithm, params::Union{ChannelWeightingParameters, WhiteningWeightingParameters}, u) = map(real(eltype(algo.S)), process(typeof(algo), params, algo.freqs))
 
 function getLinearOperator(algo::SinglePatchReconstructionAlgorithm, params::SinglePatchReconstructionParameter{<:DenseSystemMatixLoadingParameter, S}) where {S}
   return nothing
diff --git a/src/LeastSquares.jl b/src/LeastSquares.jl
index f7150f0..1997fce 100644
--- a/src/LeastSquares.jl
+++ b/src/LeastSquares.jl
@@ -38,7 +38,15 @@ function process(t::Type{<:AbstractMPIRecoAlgorithm}, params::LeastSquaresParame
   reg, args = prepareRegularization(params.reg, params)
   args[:reg] = reg
 
-  solv = createLinearSolver(params.solver, params.S; args..., weights = params.weights)
+  S = params.S
+  if !isnothing(params.weights)
+    S = ProdOp(WeightingOp(params.weights), S)
+    for l = 1:L
+      u[:, l] = params.weights.*u[:, l]
+    end
+  end
+
+  solv = createLinearSolver(params.solver, S; args...)
 
   for l=1:L
     d = solve!(solv, u[:, l])
diff --git a/src/MultiPatch.jl b/src/MultiPatch.jl
index 84f02a1..e2d4cd8 100644
--- a/src/MultiPatch.jl
+++ b/src/MultiPatch.jl
@@ -79,7 +79,7 @@ abstract type AbstractMultiPatchOperatorParameter <: AbstractMPIRecoParameters e
 # MultiPatchOperator is a type that acts as the MPI system matrix but exploits
 # its sparse structure.
 # Its very important to keep this type typestable
-mutable struct MultiPatchOperator{V<:AbstractMatrix, U<:Positions}
+mutable struct MultiPatchOperator{T, V <: AbstractMatrix{T}, U<:Positions}
   S::Vector{V}
   grid::U
   N::Int
@@ -294,7 +294,7 @@ function MultiPatchOperatorExpliciteMapping(SFs::MultiMPIFile, freq; bgCorrectio
   # now that we have all grids we can calculate the indices within the recoGrid
   xcc, xss = calculateLUT(grids, recoGrid)
 
-  return MultiPatchOperator(S, recoGrid, length(recoGrid), M*numPatches,
+  return MultiPatchOperator{eltype(first(S)), reduce(promote_type, typeof.(S)), typeof(recoGrid)}(S, recoGrid, length(recoGrid), M*numPatches,
              RowToPatch, xcc, xss, sign, numPatches, patchToSMIdx)
 end
 
@@ -411,7 +411,7 @@ function MultiPatchOperatorRegular(SFs::MultiMPIFile, freq; bgCorrection::Bool,
 
   sign = ones(Int, M, numPatches)
 
-  return MultiPatchOperator(S, recoGrid, length(recoGrid), M*numPatches,
+  return MultiPatchOperator{eltype(first(S)), reduce(promote_type, typeof.(S)), typeof(recoGrid)}(S, recoGrid, length(recoGrid), M*numPatches,
              RowToPatch, xcc, xss, sign, numPatches, patchToSMIdx)
 end
 
@@ -509,8 +509,8 @@ function kaczmarz_update_!(A,x,beta,xs,xc,j,sign)
   end
 end
 
-function initkaczmarz(Op::MultiPatchOperator,λ,weights::Vector)
-  T = typeof(real(Op.S[1][1]))
+# TODO implement for ProdOp{WeightingOp, MultiPatchOperator}
+function initkaczmarz(Op::MultiPatchOperator{T},λ) where T
   denom = T[] #zeros(T,Op.M)
   rowindex = Int64[] #zeros(Int64,Op.M)
 
@@ -518,11 +518,11 @@ function initkaczmarz(Op::MultiPatchOperator,λ,weights::Vector)
 
   if length(Op.S) == 1
     for i=1:MSub
-      s² = rownorm²(Op.S[1],i)*weights[i]^2
+      s² = rownorm²(Op.S[1],i)#*weights[i]^2
       if s²>0
         for l=1:Op.nPatches
           k = i+MSub*(l-1)
-          push!(denom,weights[i]^2/(s²+λ)) #denom[k] = weights[i]^2/(s²+λ)
+          push!(denom,1/(s²+λ)) #denom[k] = weights[i]^2/(s²+λ)
           push!(rowindex,k) #rowindex[k] = k
         end
       end
@@ -530,17 +530,17 @@ function initkaczmarz(Op::MultiPatchOperator,λ,weights::Vector)
   else
     for l=1:Op.nPatches
       for i=1:MSub
-        s² = rownorm²(Op.S[Op.patchToSMIdx[l]],i)*weights[i]^2
+        s² = rownorm²(Op.S[Op.patchToSMIdx[l]],i)#*weights[i]^2
         if s²>0
           k = i+MSub*(l-1)
-          push!(denom,weights[i]^2/(s²+λ)) #denom[k] = weights[i]^2/(s²+λ)
+          push!(denom,1/(s²+λ)) #denom[k] = weights[i]^2/(s²+λ)
           push!(rowindex,k) #rowindex[k] = k
         end
       end
     end
   end
 
-  denom, rowindex
+  Op, denom, rowindex
 end
 
 
diff --git a/src/Weighting.jl b/src/Weighting.jl
index 6aadd01..d34f569 100644
--- a/src/Weighting.jl
+++ b/src/Weighting.jl
@@ -11,8 +11,19 @@ export ChannelWeightingParameters
 Base.@kwdef struct ChannelWeightingParameters <: AbstractWeightingParameters
   channelWeights::Vector{Float64} = [1.0, 1.0, 1.0]
 end
-process(::Type{<:AbstractMPIRecoAlgorithm}, params::ChannelWeightingParameters, data::Vector{CartesianIndex{2}}) = map(x-> params.channelWeights[x[2]], data)
+process(::Type{<:AbstractMPIRecoAlgorithm}, params::ChannelWeightingParameters, freqs::Vector{CartesianIndex{2}}) = map(x-> params.channelWeights[x[2]], freqs)
 
+export WhiteningWeightingParameters
+Base.@kwdef struct WhiteningWeightingParameters <: AbstractWeightingParameters
+  whiteningMeas::MPIFile
+  tfCorrection::Bool = false
+end
+function process(::Type{<:AbstractMPIRecoAlgorithm}, params::WhiteningWeightingParameters, freqs::Vector{CartesianIndex{2}})
+  u_bg = getMeasurementsFD(params.whiteningMeas, false, frequencies=freqs, frames=measBGFrameIdx(params.whiteningMeas), bgCorrection = false, tfCorrection=false)
+  bg_std = std(u_bg, dims=3)
+  weights = minimum(abs.(vec(bg_std))) ./ abs.(vec(bg_std))
+  return weights
+end
 #=
 baremodule WeightingType
   None = 0
diff --git a/test/Reconstruction.jl b/test/Reconstruction.jl
index 69dbdbd..a0738ca 100644
--- a/test/Reconstruction.jl
+++ b/test/Reconstruction.jl
@@ -110,4 +110,25 @@ using MPIReco
   exportImage(joinpath(imgdir, "Reconstruction7c.png"), Array(c7c[1,:,:,1,1]))
   @test compareImg("Reconstruction7c.png")
   
+
+  setAll!(plan, :weightingParams, ChannelWeightingParameters(channelWeights = [1.0, 0.0, 1.0]))
+  c7d = reconstruct(build(plan), b)
+  setAll!(plan, :weightingParams, NoWeightingParameters())
+  setAll!(plan, :recChannels, 1:1)
+  c7e = reconstruct(build(plan), b)
+  setAll!(plan, :recChannels, 1:2)
+  @test isapprox(arraydata(c7d), arraydata(c7e))
+
+  setAll!(plan, :weightingParams, ChannelWeightingParameters(channelWeights = [0.0, 1.0, 1.0]))
+  c7f = reconstruct(build(plan), b)
+  setAll!(plan, :weightingParams, NoWeightingParameters())
+  setAll!(plan, :recChannels, 2:2)
+  c7g = reconstruct(build(plan), b)
+  setAll!(plan, :recChannels, 1:2)
+  @test isapprox(arraydata(c7f), arraydata(c7g))
+
+  setAll!(plan, :weightingParams, WhiteningWeightingParameters(whiteningMeas = bSF))
+  c8 = reconstruct(build(plan), b)
+  exportImage(joinpath(imgdir, "Reconstruction8.png"), Array(c8[1,:,:,1,1]))
+  @test compareImg("Reconstruction8.png")
 end
diff --git a/test/correct/Reconstruction8.png b/test/correct/Reconstruction8.png
new file mode 100644
index 0000000..bae490f
Binary files /dev/null and b/test/correct/Reconstruction8.png differ