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Hi guys
Noticed the lines on this pic when I went to pp. ISO 200 f4 1/125.
Is this banding and is it a something to worry about? I have not noticed it on any other shots except a couple of night shots at 1600iso.
Is it a problem that needs to be looked at by Maxwells? The camera is still under warranty.


Thanks
Craig

Criag; I have only seen such banding at higher that 800 iso. Certainly not at 200 iso.

Looks like it, but it'll happen on a shot that hasn't been exposed properly too, not just high ISO.

That can also happen with a dusty sensor, when you wind your CF card onto the next image, and the dust scratches the CF card as it's dragged across the sensor.

Craig, yes it is banding, and if it's only in this one image, then no, it's nothing to worry about.

In this instance the exposure is all over the place, you have a shadow from the lenshood/flash obliterating a part of the image, while it looks like the face is blown, the reality is that rest of the image seems seriously under-exposed. Look at the noise on the clothes of the passenger in the window seat for a clue as to how badly under this one is. Look too at your seat back where it's illuminated by the flash.

What does this histogram look like?

Shot taken mid flight after several drinks. Yes it is pretty crappy, a lesson in what not to do.

The histogram is steep on the left and tapers off to the right, indicating the shot is underexposed.

From what everbody has said it seems that very poor technique will cause such a problem rather than the problem being with the camera.

Thanks for the input guys.
Craig

Craig,

CraigVTR wrote:The histogram is steep on the left and tapers off to the right, indicating the shot is underexposed.

Exactly.

very poor technique will cause such a problem rather than the problem being with the camera.

That's about it, my friend.

That's a shot to be proud of Craig!!
Frame it up as a reminder about the evils of alcohol!

dosent look underexposed, that shirt is prety white. plus shots like this with the subject so close to the flash will always cause you to get a misleading histogram.
a historgram is just a graphical representation of the light values of an image. if the peak to the left goes off the edge of the graph before it reaches the baseline, then it means some pixels are black, black pixels can indicate underexposure unless of course some of the them are meant to be black.
you can underexpose a snow scene and the histogram will still have more to the right of the graph than left.

i'd be taking shots up and down the iso range, and have a good look at them.
i use 1600 iso in low light sometimes to avoid using the flash and i've never seen banding.

obzelite wrote:dosent look underexposed,

It is, and very much so. As I've already said, look at the seat backs in the immediate foreground. The noise that's there is not indicative of a correctly exposed image.

Nor too is the high level of noise that's evident on the clothing of the person sitting next to the window.

You are being decieved by the fact that person in the centre foreground appears to be blown. They're not.

The histogram in this instance is not misleading; the banding is there because of the extreme poor exposure.

if the peak to the left goes off the edge of the graph before it reaches the baseline, then it means some pixels are black,

Not exactly. There should usually be some black pixels, and some white pixels, and these would be on the histogram at either end.

Bit when the histogram is packed towards the left, it means that as well as there being a high proportion of dark to black pixels, there is also a probability that a number that simply "fell off" the LH side, so to speak.

Or underexposure.

black pixels can indicate underexposure unless of course some of the them are meant to be black.

Black pixels should, in a correctly exposed image, indicate black portions of an image.

An image falling off one end - or the other - of the histogram indicates exposure issues.

you can underexpose a snow scene and the histogram will still have more to the right of the graph than left.

Yes. Snow scenes are really easy for an exposure meter to screw up. That's what a photographer is for: to recognise those situsations where a meter can be fooled, and to make sure that, even when a meter might be fooled, the correct exposure - amongst other things - is applied to the image.

i use 1600 iso in low light sometimes to avoid using the flash and i've never seen banding.

Same here, but it's an irrelevant comparison. Poor technique leads you to use the camera beyond the boundaries of its specification. When a camera is used in that manner, unpredictable results can, and will, occur.

In this case we have a poorly exposed and executed image producing poor results. It's pretty much, to me, the expected outcome.

obzelite wrote:that shirt is prety white

Actually, in this image, it is not.

The WB is out too.