Have a large number of tif images Lightroom that are 48bits.

Looking to convert them to heic for file sizing while retaining the same quality. When using macOS native converter in finder and choosing actual size which is the highest setting to preserve data, it does drastically reduce file size by an unbelievable amount. When comparing the resulting meta data it goes from say 300 something meta tags to under a 100, but seemed all the standard tags got copied and more empty extra tags did not. One exception is the preservefilename meta which I use didn’t get copied over but made a script with exiftool to retain that.

However checked and also noticed it goes from 48 bits to 24 bits when using the macOS method which technically uses Preview app I believe. There is no setting to for higher quality, so is there another method on mac that will retain all data, and still be lossless and retain the same color depth since heic support 48 bits as well?

Using Apple Automator also has same color bit issue. Not sure if using Apple Shortcuts or retains more meta and or full color depth? Or a third party tool optimized for Apple Silicon?