Photoshop real-time posterising (banding)

[Pompey Monkey]

Sine I had an automatic update to my Photoshop (Adobe Photoshop Version: 2015.0.1 20150722.r.168 2015/07/22:23:59:59 CL 1032107  x64), I get posterised views when zoomed out:

When zoomed in, it renders the image fine:

This has no effect on the processing or final image, but it's a real pain to work with.

Does anybody know how to stop this happening?

For once, Google is failing me

[Stub Mandrel]

Looks like you've got the 'Old Grey Whistle Test Virus' ;-)

[Pompey Monkey]

Looks like you've got the 'Old Grey Whistle Test Virus' ;-)

OGWT.jpg

I can see what you're getting at lol.

[Davey-T]

There was a similar post a few weeks back, can't remember the solution, they've  probably helpfully altered a setting somewhere.

Dave

[Pompey Monkey]

Hmm - It all seemed to behave itself once the histogram got a bit fatter. Maybe it's just badly coded.

[Psychobilly]

The posts I have looked at so far seem to suggest that it's due to the time taken to process the image during zooming.

There are a few suggestions thrown up on goggle mainly to do with changing settings in the preferences...  I don't know what spec computer your using and if you are using OpenGL and OpenCL acceleration...

This might explain what's going on...

http://feedback.photoshop.com/photoshop_family/topics/why_no_16_bit_previews

http://feedback.photoshop.com/photoshop_family/topics/incorrect-rendering-of-color-and-banding-when-working-with-16bit-files-below-66-67-zoom-for-how-many-years-now

Here are my settings  I built my PC for Image and Video Processing it has  a 6 core 12 thread CPU  and 64 GB or RAM  with 3 GPU's  and multiple HDD and SSD's some of which are setup as cached pairs...

Peter...

[Pompey Monkey]

Thanks Peter, I will have a look at those settings in the morning.

BTW, I have an 8 core/thread AMD monster with 16GB RAM. It seems to cope with most things, including Pixinsight/Photoshop (whilst verifying/extracting 40-50GB archives - don't ask  )

[Pompey Monkey]

Peter, I've looked at my settings an there's not a lot different from yours, apart from the available RAM (you seem to have 64 GB!).

I did, however, load two different images in the same session: the finished image does not posterise, while the un-stretched stack still does. This confirms my suspicion that the issue is related to the histogram. Maybe the un-stretched image falls between sampling points or something?

Thanks for the guidance all the same - any new things I learn about PS are useful!

[Psychobilly]

The one that's giving problems do you have a few adjustment layers in it? The other posts I have found seem to suggest that they could be the cause of the "problem2  apparently the image data itself will be fine it's just this "mode" switch while zooming... I would have thought you have enough computing power to handle it...

Yes 64GB of RAM in this one.... Maxed it out while I could get matching modules...

Peter...

[Pompey Monkey]

The one that's giving problems do you have a few adjustment layers in it? The other posts I have found seem to suggest that they could be the cause of the "problem2  apparently the image data itself will be fine it's just this "mode" switch while zooming... I would have thought you have enough computing power to handle it...

Yes 64GB of RAM in this one.... Maxed it out while I could get matching modules...

Peter...

No, Peter, these were single layer images.

[Psychobilly]

Oh well that s that possibility ruled out then

I have trawled through the posts on the various adobe help forums and haven't come up with much else...

Peter...