I have a bracketed set of images that represent radiance data. Linearity of the data must be maintained throughout the workflow. This post explains the problem well for a non-Wolfram Language workflow. I have questions about how several functions interact with the data.

My image files are Nikon RAW files (.NEF). This means that my image data is linear in the original files.

Import

If I execute img = Import[“my.DNG”] will img contain linear data (scene referenced) or will it be processed with a gamma curve into a display referenced image? If the later is there a way to import an image and maintain linearity in the data?

ImageExposureCombine

Assume I have a list of images imageList and execute hdr = ImageExposureCombine[imageList , "HDR"] will hdr be a linear combination of the images or is tone mapping applied?

ColorConvert

ColorConvert[hdr, "Grayscale"] rescales the data between 0 and 1. Is there a way to convert color images to grayscale and preserve the original scaling?