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Ms Monny
16-06-2013, 1:44pm
I have seen these lines before in images posted here and I am noticing them when I am PPing my images from this morning. Mainly in the sky and water. Ive noticed it isn't as noticeable when saved into LR after PS Elements, as much as it is in PS Elements itself.

How do I stop this from happening..... or, correct it?

Or am I pixel peeping too much again????? :o

I have cropped into a part of the sky to show the lines....

101070

ricktas
16-06-2013, 1:47pm
happens if you 'push' the processing to far, and is more common when editing jpg files than raw files.

Ms Monny
16-06-2013, 1:50pm
Thanks Rick. Hmmmm, well, it was a dark image from my non-existent sunrise (too much cloud) but it was a raw image too. Guess it is a bad thing, hey??

ricktas
16-06-2013, 2:05pm
Thanks Rick. Hmmmm, well, it was a dark image from my non-existent sunrise (too much cloud) but it was a raw image too. Guess it is a bad thing, hey??

There is only so much you can push the processing before you will see banding like this. It is not uncommon to see when someone uses a digital graduated neutral density filter to get the same result as an on-camera filter. This is where using filters on your lenses at the time of shooting is a great benefit above digitally replicating them.

Ms Monny
16-06-2013, 2:56pm
Ah! Yes, I was dodging and then burning etc. Thanks for the tip. :)

arthurking83
16-06-2013, 9:11pm
It's called banding, or posterization.

You generally see it (firstly) in the blue channel, as this is the darker channel in most images. Being the darker channel, it usually has 'less info' and hence easier to push into posterization.

This is easily achieved if using grad filters plus polariser filters(for example on a landscape shot).

Funnily though, while you may be able to see it on screen, it may not translate in the same way onto a print.

And yes, it affects raw files too.

Someone once suggested to convert the colour profile to aRGB(from sRGB) obviously on the raw file, but that made no difference for me.
Apparently some of these instances of banding can be caused by the limited ability of sRGB to graduate the tones of certain colours.
Hence the reason aRGB exists. But in almost all of my instances of seeing this annoyance, has been due to over filtering the scene.

I did find one method of minimising it tho, and this method only works in some instances, not all.

if you see this banding, you can adding some 'digital grain' or noise to the affected area, and then(optionally) try some NR over that. Of course if the area has any fine detail of significant value doing this will usually affect the detail .... so like I said, doesn't work for all images.

FWIW: I've seen it in some instances on the SOOC raw file. Obviously too much filteringness on my part! :p

Ms Monny
16-06-2013, 9:32pm
Thanks Arthur! Most of the time it is in the sky or water, so there isn't that much detail....which means adding the digital grain and then using a NR will be fine. Might give it a go! :)

arthurking83
16-06-2013, 9:50pm
Aha! OK.. I wasn't expecting a reply to the effect that you'd actually give it a go! (oops! :P)

It may take some experimenting(coz that's what I did).

In some attempts I tried adding multiple layers of very fine grain. (I use CaptureNX2, which is almost diametrically opposed to the Adobe workflow in many ways .. so I don't know what the equivalent is in Adobe software).

But what I tried was various experiments involving grain + grain .. or NR+ grain .. or NR+NR .. and so on.
I remember one of them worked quite OK .... and I think it was grain + grain + very slight NR (with zero sharpening of course) .. I really can't remember exactly what and how .. only the idea of how to try to remove it.

If I can find the images that I have, I know I can see the exact steps I used .. but finding these images may involve a high level of random luck. :D

I suppose the suggestion(to me) to try using NR makes a lot of sense when you think about it, due to the nature of the artifacts involved. Banding is very similar to noise, so it made sense to treat it similarly to noise(but it didn't work exactly).

I would be curious too tho, if you find a way to work on the problem, so remember to either post back, or to start a new thread on how it went for ya.
Remember that part of the reason for the existence of forums such as AP is to share knowledge about photography(well that's what I think anyhow).

:)

Ms Monny
16-06-2013, 9:58pm
:lol: oh, I will try anything, Arthur!! ;)

It does make sense, and that is why I thought I would give it a go on the image from this morning. The banding isn't overly bad and it is clean sky and water, so it will be a perfect image to try it on.

I def will start a new thread with the title something like "Delete banding with Noise + NR" (or similar). I will inbox you when I do. :)