Smart Objects from TIFF vs RAW

Can someone explain how converting a TIFF inside Adobe Camera RAW (ACR) to a smart object right before opening into Photoshop compares with converting a RAW inside ACR into a smart object.

I understand that ACR provides non-destructive editing to RAW files, but I'm not sure how non-destructive ACR is to TIFF files. Because a TIFF is a rasterized file, my guess is that ACR is DE-structive to it. If this is true, why ever open a TIFF in ACR as a smart object then?

I don't know the technical details but I'd imagine that ACR does non-destructive edits to tiffs as well. Plus the Smart Object feature allows you to create different versions of your original. But I'm not at a editing computer right now so can't go into more detail!

texshooter wrote in post #16105575
...why ever open a TIFF in ACR as a smart object then?

I've never opened a TIFF... RAW files come out of my camera (and open as smart objects)

The reason you might want to open a TIFF file in ACR before opening it as a Smart Object in PS is for images that did NOT come out of a camera. You may well scan an image to 16 Bit TIFF and then open it in ACR to do your colour and possibly some exposure correction to it using ACR's tools, which are much better than those in PS. The advantage of opening as a Smart Object from ACR is that the Smart Object which is actually embedded in the PS file that it is opened into allows you to go back and make changes to the edit (non destructively for ACR) without having to change the original file. Of course embedding the file can make for a very large .PSD file!

Alan