object pixel value and noise model

[abigalexinli]

What is the unit of the pixel value in the input object image? Does the forward model model noise?

[cabouman]

The unit of the reconstruction is ALU^{-1}. So this depends on how you define an ALU. Please see Unit Conversion . If you use the NSI or Zeiss preprocessing than 1 ALU = 1 mm.

Yes, the forward model assumes additive Gaussian noise with variance alpha (1/weights) where you can control the alpha using the parameter snr_db .