Horizontal Lines in dark spots of images taken with studio lighting.

[AutumnCurl]

Hi,

Please help me determine if the faint Horizontal "lines" on the darks/grays of my images can be seen by others or if its to do with my macbook pro, camera or perhaps I've gone insane.

http://farm9.staticflickr.com/8288/7578455724_40fef28947.jpg (http://www.flickr.com/photos/76607117@N07/7578455724/) in this one i see it in the black to the right of the right arm.
Image Quality: Lossless Compressed RAW (14-bit)
Device: Nikon D800
Lens: 24-70mm f/2.8G
Focal Length: 44mm
Focus Mode: AF-C
Aperture: f/5.6
Shutter Speed: 1/320s
Exposure Mode: Manual
Exposure Comp.: 0EV
ISO Sensitivity: ISO 100
White Balance: Preset manual d-1, 0, 0
Color Space: sRGB
High ISO NR: ON (Normal)
Long Exposure NR: OFF
Active D-Lighting: OFF


http://farm9.staticflickr.com/8158/7578447856_e238b43988.jpg (http://www.flickr.com/photos/76607117@N07/7578447856/) and in the background where its is lighter than solid black.


Image Quality: Lossless Compressed RAW (14-bit)
Device: Nikon D800
Lens: 24-70mm f/2.8G
Focal Length: 38mm
Focus Mode: AF-C
Aperture: f/4
Shutter Speed: 1/250s
Exposure Mode: Manual
Exposure Comp.: 0EV
ISO Sensitivity: ISO 100
White Balance: Preset manual d-1, 0, 0
Color Space: sRGB
High ISO NR: ON (Normal)
Long Exposure NR: OFF
Active D-Lighting: OFF

I have converted images to .jpg in nikon software to upload.

I am thinking its the screen on my macbook, but can't be 100%, the lines are faint but if it was a pregnancy test they would be positive ..

This is the first time i have used the studio lighting so still learning how to use it and the d800 has a brand new CF card.

Photo is just of me testing everything, so nothing serious.

Could this be a type of moire effect caused by the combination of lights and paper background?

thanks

[kiwi]

Your shutter speed is getting to the point over 1/200s where you might start seeing the curtain effect...however...usually thats a dark horizontal band, so, yeah, not sure

[AutumnCurl]

i see very small lines about 1 mm thick, in the lighter than black areas of the background.

The d800 can sync at 1/320s :)

[kiwi]

Sync speed will differ by light and trigger also

But the symptons dont really gel

[MarkChap]

Your shutter speed is getting to the point over 1/200s where you might start seeing the curtain effect...however...usually thats a dark horizontal band, so, yeah, not sure

The band is only horizontal for landscape orientation, when in portrait orientation the curtain will leave a vertical line

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I can't actually see the lines you are talking about, these are very black in the background for me

[I @ M]

I see the bands that you mean ( I think ) but only just because the images are so tiny.

How are triggering your strobes?

The reason I ask that is most wireless triggers other than the likes of pocket wizard and maybe the new ones from phottix struggle to synch at speeds above about 1/160. The 1/320th synch speed the D800 is rate at is in conjunction with a Nikon speedlight and not with remote monoblocs.
If you are using your speedlight or even the built in flash to trigger the monoblocs optically at those speeds the banding might be from the speedlight or built in flash leaving a slight residue of light in the image.

[AutumnCurl]

they are wireless sync, but the problem i am having isn't to do with shutter speed or shutter curtains I'm starting to think its my laptop screen.

the lines i see are almost like what can happen when you scan an photo.

[kiwi]

are talking about the lighter splodge part of the image middle left on both images ?

Otherwise I cant see lines....fyi...my work LCD screen has faint vertical lines/banding too on the screen

[Ezookiel]

For me there are swirl like lines but they're vertical not horizontal, and they follow around the shoulder on the left of image, and come all the way down from the top on the right of image, but again seem to follow her contours in various places, they're hard to describe, but a bit like oily layers or something. Most noticeable in the small image, but also there if you follow the image to flickr and view it at its largest size. No idea how to help you with them, but that's what I'm seeing, and that's on my laptop monitor, which is pretty good for images so far.

[AutumnCurl]

http://farm9.staticflickr.com/8006/7580734238_2a879da86e_c.jpg (http://www.flickr.com/photos/76607117@N07/7580734238/)

http://farm8.staticflickr.com/7252/7580728932_9e26f5a879.jpg (http://www.flickr.com/photos/76607117@N07/7580728932/)

I inside the red square/rectangle i see small lines, a couple shades lighter than darkness, they might even have a hint of purple.

i think its just this laptop, will check on my husbands when he gets home, and also on the iPad..but i want to make sure its not a camera problem, or something I'm causing ( which knowing me is fairly likely)


@ezookiel
I can't see what you see LOL:confused013

[I @ M]

A bigger image and a crop is the way to go.
I can see where you mean the problem is now.
There have been a few bits of net chatter about some dud sensors in the D800 bodies that are causing banding -----

[DeanCMorgan]

I can see them quite clearly on my work PC. On both photos. Definately a distraction from a great shot.

[ricktas]

Is your laptop monitor calibrated?
Are their lines in your backdrop?
Was their light going across the scene, that might contribute to this (light leak from the light source)?
Light from another source (open door nearby etc).
Could be from processing technique
Could be from JPG compression
Could be camera sensor issue

Without us being there and knowing what was happening at the time of shooting, it is impossible for us to isolate the cause. All suggestions here are basically covering what it could be, but without being on site and seeing at the time of shooting we are all just guessing at possibilities.

[AutumnCurl]

@andrew these are shot as ISO 100 - so shouldn't be a issue and from what i can find online its at high ISO that people claim to have a problem with. Also is only on the background not in the whole image and not on all the images taken with my d800, it seems to only be in certain type of grey/black

@ rick
I know that, i am trying to work out if other people can see it the lines or not to narrow down where the problem is, if nobody else can see them, then its my laptop, not how it was shot or the camera.

Is your laptop monitor calibrated? yes.
Are their lines in your backdrop?No is a paper roll
Was their light going across the scene, that might contribute to this (light leak from the light source)? no it was night time
Light from another source (open door nearby etc). my garage is sealed like a drug lab, and even if it wasn't i find it hard to be able believe i could manage to leak like in such a uniform way.
Could be from processing technique, its not post processed
Could be from JPG compression, no because i can see it on the raw file.
Are you able to see the lines?

[MarkChap]

Try opening up the shadows and blacks in lightroom or ACR and I will bet you pounds to peanuts that what you are seeing is just some left over skin or what ever is under the black top
from the arm of you model that hasn't quite gone as black as the rest of that edge

[snappysi]

for what its worth, i cant see anything wrong.....

[ricktas]

Are you able to see the lines?

I am currently looking at AP via an uncalibrated laptop (not mine) and no I cannot see them

[swifty]

I also can't see it on my laptop. But then again its quite an old MBP, uncalibrated and due for replacement.

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But I agree with MarkChap. Open up the shadows to try and exaggerate the symptoms.

[Mark L]

FWIW I can't see the lines you're talking about. My monitor is generally OK.

[arthurking83]

It looks to be posterisation and is a common problem with 'lo fi' monitors and even some hi qual monitors too.

Basically you'll see it more readily in the shadow areas(blues are notorious for it), and the easiest way to describe it is that it may not really be there!!

The only way to fully know is to also print a copy of the images affected by the posterisation and see if it shows up in. Don't waste too much time and effort with the print tho.

I had similar issues a while back in a lot of images(landscapes) where it was showing up in the blues on my screen, but the cheapie low quality home office colour laserjet prints I tried simply didn't show up the posterisation at all.

If you could try it all again jst to confirm the issue:

same shots if you can but this time in 12bit mode on the camera instead of 14bit.

it's probably hard to capture the image in the exactly the same manner as you already did, so may try a new test to see if it makes any difference.

That is, for your new test, you'll need identical images, one in 14bit and the other in 12bit mode.
edit them in exactly the same manner and see how they both fare.
Is one better or worse than the other.

Can you see the problem in the raw file, in any raw file viewing software?
(I've only seen it in edited images and derivative jpgs).
Also, posterisation occurs with your editing processes too.
Did you try to recover the shadow detail in the affected images?

Basically two easy ways to describe it, and they can look the same:

1. image has a lot of detail and very fine tone rendering that the screen can't replicate.
in this instance you can see it on the screen, but you won't see it in a print. (you may see it in a very lo quality print tho!)

2. if the issue is processing/editing related(very unlikely with a 14bit image, but possible), not only will you see it on screen, but you will also see it in any print you make.
This form of posterisation is a lot more rare in high quality captures(ie. DSLR/14bit/etc) but can happen with extreme processing.

.. anyhow, that's what I reckon it is, and have seen in come and go on my images, but don't worry too much with it as it's not real. That is, I can see it on the screen(depending on the screen) but not in any print).

pe. Turn off High ISO NR .. you simply don't need it.(shouldn't affect ISO100 images tho).

[mikew09]

I don't see them. I am using a good quality calibrated monitor. I do see some lack of colour consistency in the black area in as much as lighter smudge. It looks to be some reflection of light off the curve of the back ground as it goes from horizontal to vertical but I had that issue also and it was attributed to a smudge of lubricant on my sensor.

Have you tried doing a shot to check for sensor dust and other sensor issues?

Actually, just checked the shot on my laptop (un-calibrated and a lower resolution) and now I see what you are saying. Actually looks a little like over processing but I wouldn't think that would be the case based on the style of shot.

Be interested to see what the out come is.

[AutumnCurl]

Thanks guys, my hubby thinks I've lost it lol because he can't see it, but then he sometimes loses his wallet on the coffee table..

Yeah its very odd, and i think its my laptop because i can not see it else where, i will do some more tests and also a print test.

As i have a macbook pro, i did find on some mac forums that recent updates have made graphics cards show some lines, however much heavier than the ones i can see. So i might do a reinstall and see what happens, I'm due for a computer upgrade as this one is a 2010 model.

The light isn't a smudge its just how the lights were placed, to take those shots, i just unpacked the gear and set it up and checked everything was working. i did take some of my cat, but i didn't think posting a photo of a cat with invisible lines that only i can see was a good idea :lol:

[arthurking83]

Again, going with Mike's reply, I'd say it's posterisation, but not real posterisation of the image.

Poserisation in an image is supposed to be a condition where the gradient of colour is supposed to be too great for the output device to display.
That is real posterisation is something that will most likely be present in a lot quality monitor, a high quality monitor and also in the print(most likely).
It'll be due to a conversion from one format(usually raw) to a lower quality format(usually jpg).
In the lower quality format the data capability will be much lower(eg 8bit) and the colour gamut will also be lower too.
So as an example of how this can manifest is going from a massive data stream of a D800 raw file in 14bit(eg. 50Mb!!) down to a low quality sRGB jpg file of about 5Mb(for an equivalent pixel dimension image)
You've compressed the image massively(both in terms of data and visual ability) and basically speaking ... something has to give.

The other type of posterisation is dependent on the viewing device, and as I said before, is not really there(in the image).
I had this a few years back on some images, where I noticed very dark blue skies looking for all the world quite massively blotchy.
When I printed out the images, this blotchiness in the blue wasn't there.
I then added another screen to my PC, and not only did the image look different(as expected), but the blotchiness in the other screen wasn't present.
(the other screen was an old CRT, which usually display colour a lot nicer than low to mid range digital screens).
The print matched the CRT display perfectly tho!.

So as Mike can see it on one screen but not the other, is a clue the fact that some screens display images differently that others do.. and so you notice stuff that is not there(in the actual file).

FWIW: the posterisation that I can see in that area you've highlighted in the image with the red square looks like wood grain. The colours that I can see tend to go from an almost purple tint to a slight green tint to a more green tint at the right most grain line.

The only form of posterisation you should worry about is the one that is real.
That is, the type that actually affects the print version of the image.
The only way I know of understanding the difference between the two types is in how the two different image types display on your screen(via your preferred editing software).
First of all your editing software needs to be colour space aware!!.
I've never seen this pseudo posterisation in any of the raw versions of the affected files, and only in the jpgs derivative files.
Usually these files need to be compressed more than the average, and this may be why they display this pseudo posterisation problem.
I really don't know why it happens, and the occurrence of this effect has always been random(for me) in the few times I've seen it.

There is no exif data in the two images you've posted or linked too, so we have no idea of which software they were editing with, how much they were compressed, what colourspace they were saved in .. etc, etc.
Being predominantly black, the conversion of the images into the jpg format(knowing that jpg is a highly compressed format!!) what usually happens is that in the conversion to jpg, the software is 'careless' in it's understanding of subtle black tones.
(very dark blue is very nearly close to black in terms of RGB values, and I think this is what's happened to my images on those occasions).

I hate to admit it, but I suppose I should, but as my preferred editing software is CaptureNX2, the only times I've seen this issue in my images has been due to this software.
So I'm interested to know which software you choose to edit with too.
But I don't blame the software as such, as the issue is random and occasional, so if it were a problem with the software, it'd happen more regularly.