Hi folks -
I know that's a provocative title, but I'm starting to wonder. I've always been a proponent of 16 bit image processing - fully convinced by the math and happy that I've never had a problem with banding or posterization in any of my images.
I teach workshops and have been drilling into my students - 16 bit, 16 bit, 16 bit. I explained the reasons why, and everyone has gone home happy.
However, I am putting together some teaching materials to show the deficiencies of editing in 8 bit mode... and I can't break the images. I took a few RAW files, processed them each into both 16 and 8 bit images and performed the same exact adjustments on each.
I've pushed, pulled, stretched and abused the 8 bit files to the point they are hugely overprocessed and look truly awful - but no posterization. This included taking some very low-contrast images and stretching the histogram out to the full extent, several sharpening iterations, some shadow/highlight, agressive curves etc.
I applied changes to hugely underexposed images as well, trying to break the shadow areas. No joy.
I did the same things to 16 bit images and got the same results - the 16 bit images were a tiny bit better when seen at 100%, but nothing to write home about.
So am I missing something basic here? Or is the 16 bit advantage only apparent on true edge-case images?