Update 8-bits filter to 16-bits filters.

[benj_v]

Hello !

Accordingly to this doc :
https://helpx.adobe.com/photoshop/using/filter-effects-reference.html

All filters that are not mentionned in this list are still producing 8-bits results even if your doc is 8/16-bits.

If I want to use for example "Noise > Dust & Scratches / Median" to remove some minor dust on a backdrop, it's obviously adding the "banding effect" even if the document is 16-bits.

Lots of filters deserve to use 16-bits process in my opinion : we start to work with strong machines these days and they can handle 16-bits processing.

Thank you for reading !

[TheDigitalDog]

It is obviously adding "banding" due to the bit depth? Please provide proof of concept that is the cause.  

[D Fosse]

8 bit filters are grayed out and inaccessible if the document is 16 bit. You can't get to them.

If you see banding, it's because you have an 8 bit display path (which most people do).

[benj_v]

Thanks for your answers.
My color management is ok : 16 bits + 10 bits display, calibrated correctly etc.
Filter "compatible" to 8 and 16 bits are available in both mode, but it doesn't mean they work with 8 or 16 bits accordingly to the document bitdepth. They can in their "pipeline" :
1. Grab data, 2. Convert to 8 bits, 3. Process, 4. Convert back to 16 bits (banding), and 5. Return this result in the 16 bits document.
In this way to see : it's still a 8-bits filter, compatible to 16 bits, working with 8-bits data.

For example : If I use on the same document (16 bits etc), a Blur filter or a Surface blur, I don't have banding. But on the same document, if I use Median or Dust & Scratches, I have banding.
  
PSD : cleanup.psd
You can activate each filter one by one to see what I mean : Don't disable the "check layer".

1: Normal document, only CheckLayer :

   

2: Gaussian Blur : No banding, perfect.

3: Surface Blur : No banding, perfect.

4: Median / Noise : Banding : 8-bits data ?

5: Dust & Scratches / Banding : 8-bits data ?

Maybe i'm wrong somewhere, you can try on the .psd !

Thank you !

[D Fosse]

Those are resampling artifacts. With extremely noisy images like this, you must view at 100%!

100% in Photoshop has nothing to do with size. It means one image pixel is represented by exactly one physical screen pixel. The significant point here is that this screen data is used for preview calculations. If that's resampled, the preview can be misleading.

Here's Median at 100%:

[TheDigitalDog]

Maybe i'm wrong somewhere, you can try on the .psd !

By @benj_v

As already outlined, the PSD proves nothing that's required for the Adobe team to take such a request seriously. That is, proof of concept of banding (outside the display path, which IS common) that is solely due to the filters used on that lower bit depth. 

Yes, the PSD is a mess. Yes, it's super noisy, and yes, you must view this at 100% (1:1), and you must do so on a fully high-bit display path to stop seeing banding in high-bit data that doesn't exist there (but in the display path). 

Here is your high-bit document, with (again) a filter that is supported for that high bit depth, producing tons of banding: 

16-bits and banding