Looking for advice on how not to get the banding in the background. In the colour version, there doesn’t appear to be any.
I’ve done a simple curves layer which seems to be where the problem started…but not noticeable. When converted to b&w it got worse.
I’ve tried different blurs.
Any ideas on how to get rid of it?
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Is this a composite: No
Hi Glennie. I haven’t run across this in B&W myself, but I don’t use it often. There are a couple of things I can think of that might cause it. If you accidentally converted the image to 8 bit somewhere along the line, adding a curves layer can cause banding. Also, if you severely underexposed the original and had to bring it up in post, there would be less information and when you tried to spread in out it could cause banding. Judging by the images I’ve seen you post in the past, I’m not betting on either of those being the case, but that’s all I can think of. As far as fixing it, you can help it by adding more blur to the background. Since the background is all out of focus anyhow, you won’t hurt the feel of the image.
A very good portrait of the horse.
The horse itself is nice and sharp - well exposed. I am no expert in banding - but simply blur the background
I wonder if adding a little noise would help?
Thank you Dennis! You hit the nail on the head. I sometimes fiddle with the 8 bit when using some of the filters. I obviously had never turned it back on. You were also spot on with the horse being a bit underexposed. Shadows were lifted all the way to the right.
I tried the blurring but wasn’t happy with the effect, so went back to the original RAW and reworked from scratch. The banding started to appear again when I’ve tried to add a diagonal gradient burn from the left top corner using a Curves Layer Adjustment.
I also tried the adding Noise like Jim suggested. The banding was improved but not wonderful.
It’s been a good learning experience!
As you have concluded for yourself already, following @Dennis_Plank 's suggestion, processing in 8 bit is the culprit. But I’m a bit confused that it appears after the conversion to B&W, as you say that the banding isn’t present in the colour version. As long as you work in 16b (or 48b, in colour), it is almost impossible to introduce this kind of banding unless you use extreme curve-adjustments. If you prepare your colour image in 48b mode and then convert to B&W, there should be no problem. There will be plenty of headspace for final adjustments of the 16b B&W image.
The human eye needs approx. 200 grey levels to perceive an image as “continuous tone”. 8 bits provide 256 levels, so there is some space to adjust, but not too much. Banding is an indication that grey levels are separated too much. 16b images have 256x256 levels, so if you work in 16b before saving as jpg, it is rare to introduce banding.
Thanks Hans!
I can see no colour banding in the RAW file, but for some idiotic reason, I worked on that RAW file
in 8 bit. I’m not one to use extreme Curve Adjustments.
When I get time today, I will go back to the RAW file and work my way through methodically.
Thanks again.
