Banding in vignettes after LR export

stickyfiddle

stickyfiddle

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255
Name
Mike
Edit My Images
Yes
Has anyone else had this and fixed it?

I'm using LR5 on Mac, processing RAFs from a Fuji XT1. It's happening when I add post-crop vignettes then export to jpg. They look fine on-screen in LR itself pre-export, but the resulting JPGs are crappy. Presume it's an issue with output quality settings, so I was hoping someone could tell me if there's any specific setting to focus on to help the quality?

The top-left of this one is a good example.


Arcus Titi by stickyfiddle, on Flickr
 
stickyfiddle said:
Presume it's an issue with output quality settings, so I was hoping someone could tell me if there's any specific setting to focus on to help the quality?
Click to expand...
It would be quicker if you shared your export settings.

JPG quality and any file size cap are the most obvious culprits.
 
You used to see this if exporting at lower bit settings - less colours available (?)
 
Processing 8 bit images causes this. As does opening and resaving jpgs, especially at low quality. Facebook's compression really exacerbates the problem.
The banding can still occur in 16 bit images in blank areas, especially where those areas have been subject to curves or levels adjustments.

Adding some fake grain or noise helps - it dithers the banding. I get best results by adding soft light layers of noise of two different sizes and blurring them slightly.
 
Right, have checked my output settings and they're as follows:

Format: JPEG
Color Space: sRGB
Quality: 60
Image size: 1600 long edge (don't enlarge)
Resolution: 240 ppi

I presume out of those it's quality which is the main candidate, then resolution. Will have a play about and report back.
 
Right, DPI and pixel dimensions make no significant difference apart from image dimensions and filesize.

Upping quality to 100 makes it a lot better, though not absolutely perfect, and triples the file size (obviously). But it's good enough for web at least.

Quality up to 80 only doubles the file size and makes it 90% better, so I reckon 90 is probably the right tradeoff.
 
juggler said:
Did you try adding some noise? I expect it would increase file size, though, even at lower quality settings.
Click to expand...

No, I didn't go that far as I'm trying to keep my processing options open as much as possible, though I think it would also work if needed. It's only really in issue where I've got a vignette or gradient on a blue sky or solid colour from a wall or whatever, but I think I have it sorted either way.
 
stickyfiddle said:
Quality: 60
Image size: 1600 long edge (don't enlarge)
Click to expand...
These two in combination I suspect.

I don't think 1600px is a native supported resolution in Flickr, best to stick to the supported dimension you share at. Or does the jpb also look bad opened on your PC directly?
 
Alastair said:
These two in combination I suspect.

I don't think 1600px is a native supported resolution in Flickr, best to stick to the supported dimension you share at. Or does the jpb also look bad opened on your PC directly?
Click to expand...

At those settings it looks pretty s*** direct on device (laptop, mac and iPhone) so happy it's not flickr compression causing it, though it may not be helping matters. I'm happy to go up to 2400 which seems to be one of flickr's native resolutions. Can't hurt!
 
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