Properties dialog resizes images while adding comments in Metadata

I have scanned a few files into TIFF format.
But when I go into the file by right-clicking -> Properties and add comments for example. Dopus resizes my files.
One of the files was originally 321Mb in size, but after adding metadata, Dopus resized it to 188Mb.

Should I be worried?
The whole point to scan it to TIFF is to have the pictures stored uncompressed and lossless


The Properties dialog is part of Windows, not part of Opus. Anything that happens in there isn’t us, and will be the same in File Explorer.

Opus’s metadata panel or dialog should be able to do the same edit and won’t resize anything (except possibly removing the history bloat old Photoshop versions added to images due to a bug in Photoshop).

Thanks for answering.
So it's actually a Windows thing even if I use Opus to open it. Today I learned.
After writing this, I saw that the pictures were compressed using LZW, which claims to be lossless.
So all is good I guess?
I'll make sure to use the Opus Metadata Panel next time, just to be sure

Thanks again

I could only speculate, as I don't know what the Properties dialog is doing exactly.

You could convert the old and new images to BMP and see if the files are identical. That will tell you if any pixel-level details changed. But it could also be removing or modifying other data, like color profiles, which that kind of test would not reveal.