Backlight banding

[S. Roberts]

Hello! I received prints only to find horrid banding in the whites. I've printed several back-light photos and never had a problem until today. Is this something I can remedy through adding noise? Is there a better solution? Here is a 700 crop, the jpg I sent for print and for fun, a cell shot of the print. I print at Pro DPI. I have the Spyder5. Thank you!

[Damien Symonds]

May I see the SOOR?

[S. Roberts]

I will post it in a few hours when I'm back home. Thank you. 

[Damien Symonds]

Thanks.  I need to see if there was any degree of Photoshop editing to that area.

[S. Roberts]

Hi Damien,

Here is the SOOR. I appreciate your time.

[Damien Symonds]

Oh, right.  Yes, significant editing.

When I compare your SOOR to your final edit, I can see the slight light halo around their heads.  Can you see it too?  That's where the banding happened.

[S. Roberts]

Yes, I added a levels adjustment to bring down the window brightness (backlight). I can see the halo when I zoom in. It's a first and I shoot & print this set up often. 1. How can I fix it? 2. I can barely see a hint of banding. Is there something I can do to check for banding before I print? 3. Which class should I take to help? (I've done RAW.) 

Thank you. 

[Damien Symonds]

If you add a Levels layer to the print file, and pull the black slider across REALLY aggressively, do you see the banding appear?

[S. Roberts]

Yes. Wow. I can really see it now. 

[Damien Symonds]

Great.

So basically, your levels method should have worked just fine.  The trouble was, you didn't allow it to go safely into their hair.

[S. Roberts]

That would stop the banding? 

[Damien Symonds]

Yep, for sure. The problem is that the banding is occurring right where the edge of your mask is, yes? Your mask fell off just before the hair started.

[S. Roberts]

I am referring to the several diagonal lines, in a squiggle sort of pattern just above the halo (poor masking). Maybe banding is the wrong word. It stands out in the picture of the printed photo, and I can see it in the file when I pull the blacks aggressively in the levels layer (as you suggested).

[S. Roberts]

These may show the variegated color on the print. 

[Damien Symonds]

Ok ... so this is a question I should have asked earlier.  Exactly how many of your adjustment layers are affecting that background area?

[S. Roberts]

Just the one levels layer. I put the *test levels layer on the top, pulled the blacks aggressively, then turned each layer below on and off. The banding occurred with the levels adjustment layer use to bring down the whites and masked into that window backlight area.

[Damien Symonds]

Ok, so if you add that same test Levels layer to the SOOR, and pull the black slider in aggressively, was there ANY detail in that area?

When I try it, I can't see any.

[S. Roberts]

There was no banding evident with the SOOR. It looks smooth, if that's what you mean by no detail. 

[Damien Symonds]

Well, it's "smooth" because there is literally no detail, right?  It's completely blown out?

[S. Roberts]

Other than the detail toward the bottom of the curtain, yes. The window is blown. 

[Damien Symonds]

Right.  So for banding to have occurred where you showed me, it must have been caused by your masking.

So, Alt-click on the mask of the levels layer you used to darken the background, and show me a screenshot of it.

[S. Roberts]

Here is the masking.

[Damien Symonds]

Yep.  Now do you understand the problem?

[Damien Symonds]

It should look like this:

[S. Roberts]

Yes (er, I hope so)! So, I re-did levels layer and masked the other way. I used checked my masking by using the test levels layer with the aggressive blacks to make sure there was no banding in the blown out area. Here is that mask.