GeForces don't support 30-bit color, only Quadros do.
However, some applications (Lightroom for one) apply dithering to remove the visible banding - but the signal is still 8-bit.
Thanks D Fosse,
but that's not right.
GeForce 1070 do support 10bpc (30 bit) via DisplayPort and since Windows 10 Creators Update they are supported by the OS too..
It seems that the problem is just the CC..
If it's a new OS feature you'll need to wait for a new Photoshop release.
The GeForce drivers don't support 30-bit color. There's no special driver for the 1070 as opposed to other GeForces. I went to NVidia's site and checked, and there's no mention of 30 bit support in the extended specs (or anywhere else).
To get 30-bit color the whole display pipeline needs to support it - OS > application > video card > video driver > interface > monitor.
You need a Quadro card, with a Quadro driver, to get 30-bit color. This is just market segmenting. It's the same with AMD (Radeon vs. FirePro). And even then it's pretty erratic and doesn't always work.
If you have applications that don't display the 256 individual steps, they use dithering as a workaround.
As it turns out, you're partly right, and I was partly wrong. 30-bit color is supported in Direct X, but not OpenGL which is what Photoshop uses. From NVidia support:
"NVIDIA Geforce graphics cards have offered 10-bit per color out to a full screen Direct X surface since the Geforce 200 series GPUs. Due to the way most applications use traditional Windows API functions to create the application UI and viewport display, this method is not used for professional applications such as Adobe Premiere Pro and Adobe Photoshop. These programs use OpenGL 10-bit per color buffers which require an NVIDIA Quadro GPU with DisplayPort connector. A small number of monitors support 10-bit per color with Quadro graphics cards over DVI."
Thanks D Fosse!
I know that 2011 post, but I hoped that something moved on in 6 years..
Is there a chance that Adobe will add this support to the roadmap now that Windows too has the support for 10 bit?
Thank you and have a nice evening,
It's more a question of when NVidia will support it. Photoshop is ready - as long as you have a Quadro.
You can't seriously expect Adobe to dumb down Photoshop to use Direct X instead of OpenGL.
Windows has had full 30 bit support since Windows 7, there's nothing new now.