These numbers I can explain.mawyatt wrote:The RAW files were specified as uncompressed in the D800E, and vary from 77.4MB to 79.5MB. The TIFF files created in LR from these RAW files are all the same size, 216.9MB!! The final stacked rendering from Zerene is also 216.9MB!!
Thom Hogan's "Complete Guide to the Nikon D800/D800E" (page 184) lists "74.4 MB" as being a typical size for an FX 14-bit NEF with no compression. He also notes that:
FX pixel count is 7360x4912 = 36,152,320 pixels.NEF file sizes vary with the amount of detail in a scene. The more detail in the scene, the larger the file will be. These sizes are therefore approximate. The less detail in the scene, the smaller the file will be. Remember that your JPEG settings (mostly sharpening and noise reduction) will impact the size of the embedded JPEG, too. Most NEF file sizes do tend to be within 15% of the number I report here.
16-bit TIFF files produced by Zerene Stacker will have 6 bytes per pixel, giving 6*36,152,320 = 216,913,920 bytes for image data. There will be some added to that for headers and color profile, plus any metadata that is copied from the source images. These files do not contain thumbnails and by default are not compressed, so there should be little or no variability.
Given that the file sizes are the same, I expect that this description applies to the Lightroom TIFFs also.