In what way has PNG not already replaced TIFF?

emptybits · on Feb 7, 2020

BTW, I know this because I recently embarked on some photo import/edit/management scripts and wondered the same thing you did: "Why isn't PNG a thing yet??" There are reasons. A few, from minor to major IMO:

TIFF acknowledges EXIF and IPTC as first class data. PNG added EXIF data as an official extension a couple of years ago and I know ExifTool does support it but I'd want to check all applications in a workflow for import/edit/export support before trusting it.

TIFF supports multiple pages (images) per file and also multilayer images (ala photo-editing).

TIFF supports various colour spaces like CMYK and LAB. AFAIK, PNG only supports RGB/RGBA so for image or print professionals, that could be a non-starter.

So I get why PNG can't warm photographers' hearts yet. Witness still the most common workflows: RAW->TIFF & RAW->JPEG.

labster · on Feb 7, 2020

TIFF is a container format that allows you to add other features into the file. A good example of this is GeoTIFF, which is like a grid data file that also happens to be viewable as an image.