Embed Original Raw File embeds a bit-for-bit copy of the original raw file in the DNG, from which it can be extracted at any time.Linear DNGs are much larger than mosaic-format ones, so if you’re thinking you can save processing time by converting to linear DNG, think again-any savings in processing time are offset by the extra time needed to read the data.
This option is mostly useful if you want to use a DNG-compliant raw converter other than Camera Raw on images from a camera with a mosaic pattern that isn’t supported by the raw converter. Convert to Linear Image saves a demosaiced version of the image.You can convert a DNG saved this way to a linear DNG, but not vice versa. Use this option if you want to be able to use all of Camera Raw’s features. Preserve Raw Image preserves the raw pixel data in its original mosaic format.And yes, the compression is truly lossless. Unless you own stock in a hard drive vendor, we can’t think of a reason to turn this off. Compression (lossless) applies lossless conversion.