NEF files changes to _KIR NEF files ?

[abamilen]

I have a very strange thing happening when I am copying some files from one external HD to another one. When the files are transferred its been renamed to KIR NEF files. It was before named _DSC2304NEF. for example.The files on the HD that I was copying from is also renamed with the same type of name. The files then are smaller than it was before. This is files containing photos ( I'm shooting in RAW mode ) so its quite annoying that the files are getting smaller. I´m shooting in RAW to get as much as possible data from the file.
Another strange thing as well. When I'm trying to copy a file of around 300GB from one disc, to another disc with 400GB available, its telling me I need another 240 GB of space to do the copying ....

What is happening here ?

 

[Cory Cooper]

Hello and welcome.

Sorry for the delayed response.

• Which model Mac?
• Which version of macOS?
• Which brand/model/format are the external drives?
• Which brand/model digital camera is creating the NEF files?
• Are you simply copying the NEF files from folders from one drive to another, or are they in Photos, Lightroom, or another photo library/management application?

C