Bypass image processing / access original source image?

Users of our Discourse forum have a device that photographs and displays holographic images. Think 3D x 2. I would like to allow users to upload this format of holographic still (3.3 MB, 8.3 Megapixel, 3840 x 2160) directly into their posts.

Uploading appears to work OK, but when I download the image from Discourse, the dimensions are still 3840 x 2160, but the image size has shrunken from 3.3 MB to 2.6 MB… and all of the dimensional metadata embedded in the image is gone

Relevant SiteSettings:

max image size kb = 5000
max image megapixels = 40
max image width = 3840
max image height = 2160
strip image metadata = false
min ratio to crop = 0.45
create thumbnails = false
enable s3 uploads = true

Is there a straight forward way to bypass image processing or specifically bypass the removal of certain metadata? I’ve already set “strip image metadata = false”…

Upload them as compressed .zip files, so they won’t be processed as images.